Thin-film Techniques Research Articles

Active aluminum promoted copper uptake by Chinese cabbage grown in an acidic Cu-contaminated soil: A new insight with the diffusive gradients in thin-films technique (DGT)

Active aluminum promoted copper uptake by Chinese cabbage grown in an acidic Cu-contaminated soil: A new insight with the diffusive gradients in thin-films technique (DGT)

Double-faced diffusive gradient in thin films sampler (df-DGT): Proposing an improved DGT sampler design for water deployments.

The Diffusive Gradients in Thin Films (DGT) technique has become the most widely used passive sampling method for inorganic compounds. This widespread adoption can be partly attributed to the development of new binding phases that facilitate the sampling of numerous analytes. In contrast, to date, the DGT sampler for inorganic compounds has not seen any significant design improvements. In this manuscript, a new design for the DGT sampler is proposed. The new design, referred to as the Double-Faced DGT (df-DGT) sampler, features dual sampling windows, enabling a twofold increase in analyte mass uptake compared to the conventional DGT sampler. The proposed sampler was characterized for Cd, Co, Mn, Ni, and Zn by performing the following tests: deployment curves, the effect of the diffusive boundary layer (DBL), pH, ionic strength and deployment in synthetic samplers. It was demonstrated that the df-DGT sampler can accumulate twice the mass over time compared to the conventional DGT sampler. The effects of the DBL, pH, and ionic strength on the measurements of Cd, Co, Mn, Ni, and Zn, when sampling with the df-DGT, were consistent with those previously reported for the conventional DGT sampler. When the df-DGT sampler and the DGT sampler were deployed simultaneously in synthetic samples with varying concentrations of Cd, Co, Mn, Ni, and Zn, no significant differences were observed (at the 95% confidence level) in the results obtained from both samplers. To the best of our knowledge, this is the first time a new DGT sampler, featuring conceptual innovations, is being proposed for sampling inorganic species in water. The proposed sampler is twice as effective in terms of mass uptake and is useful for short deployments or enhancing sensitivity. In the future, the application of this sampler could potentially be expanded to other uses, such as o-DGT.

Utilizing diffusive gradients in thin films technique for enhanced surveillance of drug abuse in two Chinese urban communities

Utilizing diffusive gradients in thin films technique for enhanced surveillance of drug abuse in two Chinese urban communities

Enhancing the prediction of arsenic bioavailability in soils with the diffusive gradient in thin film technique.

The diffusive gradient in thin films technique (DGT), with a resin gel based on Lewatit® FO 36 was used for the first time to predict arsenic (As) bioavailability in soils collected in different environmental contexts. The predicted bioavailability, determined by fluxes to DGT, was compared with the bioavailability and bioaccumulation in the plants (Calendula officinalis), where a strong correlation was observed (r = 0.8857 (CE/Croots) and r = 0.9208 (CE/Cshoots); p < 0.05; n > 40). Arsenic, predominantly accumulated in the roots of plants from all soil samples, reached concentration up to 507.8 mg kg-1. To better understand the As distribution within the various soil-bearing phases, sequential extraction procedures were performed and revealed low mobility and availability of As, particularly in A and R soil samples, where As pollution is primarily caused by anthropogenic activities such as mining and industrial activities. The obtained results show that Calendula officinalis plants can be grown on soils contaminated by arsenic, while the low translocation factors indicate that accumulate arsenic predominantly in the root system.

Sediment Ballet: Unveiling the Dynamics of Metal Bioavailability in Sediments Following Resuspension and Reequilibration.

Assessing the risk of metal-contaminated sediments under disturbed conditions is challenging due to the lack of methods that capture instant changes in metal bioavailability. Existing approaches provide inadequate understandings of the processes regulating metal bioavailability under nonequilibrium conditions. Experiments were conducted to improve our understanding of the metal bioavailability dynamics induced by sediment resuspension and subsequent redeposition (reequilibration). An isotopically modified bioassay, a novel stable isotope tracing technique, was used to measure metal bioavailability (assimilation rates) to clams within short time windows. Changes in metal partitioning were characterized by porewater analysis using in situ extraction and the diffusive gradients in thin-films technique. Results showed that sediment resuspension released metals into porewater, while reequilibration scavenged metals from the porewater. The assimilation rates of Ni, Cu, and Pb increased with the resuspension time, aligning with increasing porewater concentrations. Unexpectedly, during reequilibration, the metal assimilation rates did not decrease. The discrepancies between bioavailability to the clam and porewater extrapolations may be due to differing sustained conditions of metals in sediments. Overall, this study unveils the metal bioavailability dynamics in nonequilibrium sediments, which could not be accurately predicted relying solely on porewater analysis. Incorporating rapid bioassays to determine bioavailability offers a valuable tool for robust ecological risk assessment.

From oxide epitaxy to freestanding membranes: Opportunities and challenges.

Motivated by the growing demand to integrate functional oxides with dissimilar materials, numerous studies have been undertaken to detach a functional oxide film from its original substrate, effectively forming a membrane, which can then be affixed to the desired host material. This review article is centered on the synthesis of functional oxide membranes, encompassing various approaches to their synthesis, exfoliation, and transfer techniques. First, we explore the characteristics of thin-film growth techniques with emphasis on molecular beam epitaxy. We then examine the fundamental principles and pivotal factors underlying three key approaches of creating membranes: (i) chemical lift-off, (ii) the two-dimensional layer-assisted lift-off, and (iii) spalling. We review the methods of exfoliation and transfer for each approach. Last, we provide an outlook into the future of oxide membranes, highlighting their applications and emerging properties.

Impact of trace elements (total and labile fraction) on the anaerobic digestion activity and microbial community structure

Trace elements (TEs) in anaerobic digestion (AD) are known to be essential for optimal biogas production, but inhibitive in excessive concentrations. However, the mechanisms of inhibition are not fully understood. The effects of the addition essential TEs (Co, Cu and Ni) and a non-essential TE (Cd) on the microbial community structure of AD were studied in lab-scale reactors, using total TE concentrations that ranged from 0 to 100 μM. Reactor performance was assessed by monitoring biogas production. The labile fraction of TEs (the most bioaccessible species) was determined by diffusive gradients in thin-films technique. Prokaryotic community composition was characterized through high throughput sequencing (HTS) targeting archaea and bacteria and qPCR to evaluate changes in methanogens and metal resistance genes. Only a minor fraction of added TEs was labile and it decreased over time, with Ni being the most labile. Although only a minor fraction of spiked concentration was labile, all TEs inhibited biogas production at the highest spiking concentration (100 μM), with higher inhibition observed for Cd and Ni. HTS and qPCR revealed changes, particularly in archaea, with reduced relative abundance at higher TE concentrations. Shifts in prokaryotic communities suggest alterations in AD metabolic pathways. High inhibition of biogas was linked to reduced diversity, dominance of the bacterial genus Klebsiella and changes in the ratio acetoclastic / hydrogenotrophic methanogens. This study addresses a research gap in understanding how TEs inhibit AD, and provides a strategy to improve TE dosing by monitoring the labile fraction of TEs to avoid overdosing.

Nitrogen, sulfur, iron, and microbial communities co-shape the seasonal biogeochemical behaviors of As and Sb in coastal tidal flat wetlands associated with rivers

Arsenic (As) and antimony (Sb) are affected by complex biogeochemical processes in coastal ecosystems. However, the influence of N, S, Fe, and microbial communities on the biogeochemistry of As and Sb in coastal tidal flat wetlands remain uncertain, particularly when rivers flow into these areas. This study combined diffusive gradients in the thin-film technique with high-throughput sequencing to investigate the release and vertical distribution of As and Sb in river and coastal tidal flat wetland sediments. The results indicated a distinct stratification phenomenon in the As release at depths ranging from 20 mm to −150 mm. At river sites, the release of As occurred in the upper layer (above −40 mm), with peak values of 4.3 and 9.3 μg/L at HS and SY sites in summer, respectively, likely due to anaerobic ammonium oxidation. In the lower layer (below −40 mm), both As and Sb were released, and this was possibly due to Fe reduction. However, at the coastal tidal flat sites, the release of As and Sb may have been driven by anaerobic ammonium oxidation, dissimilatory nitrate reduction to ammonium, sulfate reduction, and Fe reduction. At the river sites, As exhibited increased activity during the summer, and the residual forms were converted more easily into mobile forms. Sb remained relatively stable during both winter and summer. Conversely, both As and Sb primarily existed in residual forms and exhibited higher stability during summer in the coastal tidal flat sites. The microbial phyla Nitrospirota (3.6−7.0 %) and Acidobacteriota (9.5−10.2 %) were more prevalent at the river sites, whereas Desulfobacterota (8.8−12.0 %) and Firmicutes (0.13−27.9 %) were more prevalent at the coastal tidal flat sites. The bacterial genera involved in the N, S, and Fe transformation processes differed between the two sites, and they were primarily Thiobacillus, Limnobacter, and Sulfurovum at the river sites and Sva1033, Anaeromyxobacter, and Sva0485 at the coastal tidal flat sites. In this study, the microorganisms that mediated N, S, and Fe complex processes at various depths in the sediment–water interface were decoupled to elucidate the effect of these processes on the biogeochemical behavior of As and Sb as they move from rivers to coastal tidal flat wetlands.

Effect of biodegradable microplastics and Cd co-pollution on Cd bioavailability and plastisphere in soil-plant system

Biodegradable plastics (BPs) are regarded as ecomaterials and are emerging as a substitute for traditional non-degradable plastics. However, the information on the interaction between biodegradable microplastics (BMPs) and cadmium (Cd) in agricultural soil is still limited. Here, lettuce plants were cultured in BMPs (polylactic acid (PLA) MPs and poly(butylene-adipate-co-terephthalate) (PBAT) MPs) and Cd co-polluted soil for 35 days. The results show that diffusive gradient in thin films technique (DGT) but not diethylenetriaminepentaacetic acid (DTPA) extraction method greatly improved the prediction reliability of Cd bioavailability in non-rhizosphere soil treated with BMPs (R2 = 0.860). BMPs increased the Cd bioavailability in non-rhizosphere soil indirectly by decreasing soil pH, cation exchange capacity (CEC), and dissolved organic carbon (DOC), rather than by directly adsorbing Cd on their surface. PLA MPs incubated in rhizosphere soil showed more considerable degradation with extremely obvious cavities and the fracture of ester functional groups on their surface than PBAT MPs. BMPs could provide ecological niches to colonize and induce microorganisms associated with BMPs’ degradation to occupy a more dominant position. In addition, Cd only affected the composition and function of microbial communities in soil but not on BMPs. However, co-exposure to BMPs and Cd significantly reduced the degrees of co-occurrence network of fungal communities on PLA MPs and PBAT MPs by 37.7% and 26.7%, respectively, compared to single exposure to BMPs.

Bufonis venenum extract loaded novel cholesterol-free liposome for the treatment of hepatocellular carcinoma.

This study aims to improve the solubility and the toxicity of Bufonis venenum, and finally enhance the therapeutic outcomes of hepatocellular carcinoma (HCC). The cholesterol-free liposomes simultaneously encapsulate bufadienolides and indolealkylamines (Non-Cholesterol-Bufonis Venenum Extract-Liposome, Non-Chol-BVE-LP) was prepared by the thin-film evaporation technique. In vitro, the cytotoxicity, cell apoptosis study, cellular uptake and hemolysis studies were evaluated in HepG2 cells. In vivo, the biodistribution and anti-tumor activity studies were conducted in BALB/C mice with HepG2 cells. The liposomes showed good size distribution, encapsulation efficiency drug loading capacity and slower drug release. Non-Chol-BVE-LP had higher cytotoxicity on HepG2 cells and induced more apoptosis on HepG2 Cells compared with BVE. In addition, the liposomes could accumulate in tumor by passive targeting, thus facilitating the anti-tumor effects. In vivo, Non-Chol-BVE-LP showed equivalent anti-tumor efficacy to the first-line anti-HCC drug sorafenib. The study provided new ideas for the development and clinical application of Bufonis venenum related formulation and offered new drug for the treatment of HCC.

Sr Migration and Gd-Ce-Zr Interdiffusion in Solid Oxide Cells Under Different Fabrication and Testing Conditions

This work aims to understand how solid oxide cell (SOC) fabrication methods and SOC operating conditions affect Sr migration into the yttria stabilized zirconia (YSZ) electrolyte through the rare-earth doped ceria barrier layer. Ni-YSZ electrode-supported SOCs and coupons were fabricated using (La0.6Sr0.4)0.95Co0.2Fe0.8O3-δ-Gd0.1Ce0.9O2-δ (LSCF-GDC) oxygen electrode and GDC or samaria-doped ceria (SDC) barrier layer. Barrier layers were either screen printed and sintered to YSZ electrolyte layer at 1260 °C for 2h, or deposited using thin film deposition techniques such as PLD, electron beam and sputtering. LSCF-GDC electrode layer was sintered onto the GDC barrier at different temperatures from 950 to 1100°C for 2h to determine the effect of firing temperature and barrier layer thickness on Sr migration. Several SOCs were tested at 750°C in a wide range of operating conditions, both in SOFC and SOEC mode, for up to 12,000 hours. The GDC/YSZ interfaces in coupons and SOCs were examined using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). Sr-Zr rich phase formation at GDC/YSZ interface was observed in coupons with LSCF-GDC sintered at 1100°C, but not in the other coupons sintered below 1100°C, unless the barrier layer was too thin and porous. Furthermore, no Sr migration into YSZ was observed in SOECs with varying testing time from 0 h to12,000 h. In addition, Gd and Ce diffusion into YSZ occurred when GDC was fired at 1260°C, but not in cells with GDC deposited using thin film techniques without additional high temperature firing. No significant difference was noted in the GDC-YSZ interdiffusion layer growth after SOC testing for 1,000-12,000 h. Aberration-corrected scanning transmission electron microscopy (STEM) was involved to identify the composition and crystal structure of the Sr-Zr rich phase, which was demonstrated to be SrZrO3 phase. After the long-term SOC tests, no SrZrO3 phase or Sr migration through GDC grain boundaries was observed in cells with 5-7 microns thick porous GDC barrier. This presentation will demonstrate how optimization of fabrication conditions, thermal treatment and fabrication techniques, could mitigate the formation of the insulating SrZrO3 phase.

Cycle Performance of Si Film Negative Electrodes with Lithium Fluoride Coating As an Artificial SEI

Introduction There is a growing need for high-capacity lithium-ion batteries as a power source for electric vehicles and a backup power source for renewable energy. Si negative electrodes, which have about ten times the capacity of conventional graphite electrodes, are expected to be used practically to increase the capacity of lithium-ion batteries. However, there are still issues that need to be addressed before Si electrodes can be used practically. One of them is the decomposition of electrolytes on the negative electrode surface. In conventional lithium-ion batteries, a small amount of additive such as FEC is added to the electrolyte to suppress electrolyte decomposition. However, suppression of the electrolyte decomposition is still difficult for Si electrodes. On the other hand, it has been found that lithium fluoride (LiF) in the SEI film formed from the decomposition products of the electrolyte improves charge and discharge properties of Si electrode.1-3 In this study, we aimed to suppress electrolyte decomposition and improve cycle life by forming a LiF layer as an artificial SEI on the Si electrode using a thin-film technique. Experimental Amorphous Si thin films, 100 nm in thickness, were prepared on copper foil by RF magnetron sputtering. Subsequently, LiF layers were deposited on the Si surfaces by sputtering with varying thicknesses. The thickness of the LiF layers was measured by a stylus surface profiler. The LiF-coated Si films were transferred to an Ar-filled glovebox without exposure to air and punched into disks 13 mm in diameter. A coin-type half-cell (CR2032) was assembled with the LiF-coated Si film as a working electrode and a Li disk of 14 mm in diameter as a counter electrode. A solution of 1 M LiPF6 dissolved in a mixture of ethylene carbonate and diethyl carbonate was used as an electrolyte. Charge and discharge characteristics were measured with a C/3 rate in a thermostatic chamber at 30°C. After cycling, the coin cells were disassembled in the glovebox, the Si electrodes were rinsed with dimethyl carbonate, and the Si electrode surfaces were observed with a scanning electron microscope (SEM). Result and Discussion Figure 1 shows variations in discharge capacity of the Si film electrodes with and without LiF coating. The discharge capacity of the Si electrode without LiF rapidly dropped after 10 cycles, but LiF coating significantly improved cyclability. Capacity retention at the 100th cycle, compared to that at the 5th cycle, increased from 4% without LiF to 52% with LiF coating. LiF coating also improved initial Coulombic efficiency from 89.9% to 92.5%, suggesting that LiF coating suppresses electrolyte decomposition. Si electrode surfaces after 30 cycles were observed by SEM as shown in Fig. 2. Exfoliation of the Si film without LiF was observed in many areas after 30 cycles, but it was suppressed by LiF coating. LiF coating is effective in improving the cycle performance of Si negative electrodes as an artificial SEI. Acknowledgments This work was supported by GteX Program Japan Grant Number JPMJGX23S3 and JSPS KAKENHI Grant Number 2201967.

Selective-Area Growth of Crystal Phase Transition Wurtzite InP Film

Nano light-emitting diodes (LEDs) for next generation display devices are required for high brightness, high luminous efficiency, and high color rendering property in visible color region. Especially, yellow color wavelength still lacks moderate-candidate materials. In case of conventional AlGaInP, the bandgap becomes indirect with increasing Al composition, results in low luminous efficiency. While in case of nitride semiconductors, crystal growth of narrow gap nitride is difficult and also decrease luminous efficiency. With this regards, wurtzite (WZ) phosphide (P)-related semiconductors by crystal phase transition are expected to overcome this issue. The crystal phase transition occur that the crystal structure of III-V compound semiconductor stabilized metastable structure and changes the bandgap to direct transition [A. De et al., Phys Rev. B, 81, 155210 (2010)]. Among the WZ III-Vs, WZ-AlInP has a bandgap of the yellow color wavelength. Therefore, exploring the growth technique for pure WZ-AlInP large-area film is important for the application of nano LEDs. Disc-shape WZ-InP was reported [S. Mauthe et al., IEEE J. Sel. Top. Quantum Electron., 25, 8300507 (2019), P. Staudinger et al., Nanotechnology, 32, 075605 (2021)]. However, there was no report on growth technique for large-area WZ III-Vs thin films. Here, we investigated growth in selective-area growth of WZ-InP film toward large-area growth. In experiment, 20 nm-thick SiO2 sputtered InP(111)A substrates were used for the selective-area growth. For mask openings, periodical openings were formed using lithography and wet etching. Two kinds of shape were designed as mask openings. One was hexagonal openings surrounded with four short {-211} and two long {-211} sides. Another design was octagonal openings surrounded with six short {-211} and two long {-110} sides. Then, InP was grown by low-pressure horizontal MOVPE with H2 carrier gas. The source materials were trimethylindium (TMIn) and tertiarybutylphosphine (TBP). The partial pressure ratio of TMIn and TBP was 24. The growth temperature was 660 ºC. Growth time for the InP was varied from 10 - 45 min. Next, two step growth was introduced for the InP growth to investigate the growth morphologies toward epitaxial lateral-overgrowth (ELO). After the growth of InP fins in 20 min, InP was grown continuously for 15 min at 600 ºC with same V/III partial pressure ratio. The InP hexagonal- and octagonal-shaped fins as following the designed shape of the mask openings were grown on the substrates. Transmission electron microscopy (TEM) images and selective-area electron diffraction (SAED) patterns indicated that the InP fins had WZ structure in both mask openings. And photoluminescence (PL) spectra showed two peaks at 1.46 eV and 1.42 eV originated from the WZ-InP fins and the interface between WZ-InP fins and zinc-blende (ZB)-InP substrate, respectively. The interesting point that the average fin height of both InP fins had saturated value due to the surface diffusion length of In adatoms. After the fin height reached to the saturation value, the average width of the InP fins was increased. Eventually, the InP fins exhibited random coalescence. The PL spectra of the coalesced fins showed the peak at 1.37 eV and 1.45 eV meaning that the coalesced InP fins had WZ structure including the ZB structure. TEM image and SAED pattern showed the crystal structure of the InP fin inside the coalesced InP part. The bottom of the InP fin had WZ and ZB mixed structure, while the top of the InP fin exhibited ZB structure. As for coalescence part, the crystal structure of the bottom of the coalesced InP part had WZ and ZB mixed structure, and the top of the coalesced InP part had WZ structure. These results mean that the ELO growth process continuously formed from the sidewalls of the WZ-InP fins, while top of the WZ-InP fin and ELO layer, the InP layer formed ZB phase. This was because that the diffused In adatoms on sidewalls were not reached to top planes of the coalesced layer and the effective V/III ratio was decreased. To suppress the random coalescence growth and unintentional formation of the ZB-InP, two-step selective-area growth combining the fin growth and ELO were introduced. The two-step growth successfully formed large area films. The PL spectra of the InP large-area film had the peaks at 1.34 eV, 1.39 eV, and 1.42 eV. The peak at 1.34 eV means ZB-InP bandgap. The peaks at 1.39 eV and 1.42 eV mean ZB and WZ mixed structure. These PL results assumed that the ZB-InP layer was grown on large-area WZ-InP film. Further investigation of the crystal structure of the large-area InP films by TEM will be discussed on the day.

Improvement of Air Stability of Garnet-Type Li7La3Zr2O12 Solid-State Electrolyte through F-Doping Strategy

Garnet-type Li7La3Zr2O12 (LLZO) stands out among various solid-state electrolytes (SSEs) due to its exceptional potential for commercializing Li metal batteries.1 This is attributed to its high Li-ion conductivity, reaching approximately 10-4 S/cm in its cubic phase.2 Dopant stabilization strategies have been widely employed in LLZO materials to promote the formation of cubic-LLZO (c-LLZO), involving cation substitution effects on Li+, La3+, and Zr4+ lattice sites.3 However, substituting cations on the Li site can pose challenges to Li-ion conduction pathways. Consequently, one emerging trend is the use of halogen species (F-, Cl-, Br-) as dopants on the O site, aiming to enhance ion migration without sacrificing Li content.4 This novel concept shows promise in improving Li-ion conductivity in garnet-based SSEs.5However, most of the studies on halogen doping in LLZO have been conducted only through computational simulations and calculations without the experimental results verification.6 Unfortunately, the conventional sintering process at high temperatures (> 1100°C) poses challenges such as lithium loss7, formation of Li2CO3.8 To achieve excellent c-LLZO at low temperatures, PVD methods such as RF magnetron sputtering9 and PLD10 have been considered effective techniques for forming thin-film LLZO. The layer-by-layer deposition and post-annealing processes are crucial for achieving dense, highly controllable, and uniformly doped C-LLZO thin films.In this report, we propose a rational material design approach for the layer-by-layer microstructure of LiF-LLZO using the thin-film deposition technique (see Supplementary Information for details). The comprehensive X-ray photoelectron spectroscopy (XPS) spectra trace the Li2CO3 distribution inside the depth profile evolution of LLZO after a hostile environment, shedding light on the ambient stability of SSEs. Thermal decomposed LiF serves the dual role of providing supplemental Li and F dopant after by post-annealing. Furthermore, the remained LiF protection on LLZO and F-LLZO was systematically studied about the capability of against the Li2CO3 immersing inside LLZO. Our perspective offers an innovation strategy to solve the Li2CO3 problem and Li-loss simultaneously, which can be extended to other oxide-base SSEs.Reference: Murugan, V. Thangadurai, W. Weppner, Angew. Chem.-Int. Edit. 2007, 46, 7778.V. Thangadurai, S. Narayanan, D. Pinzaru, Chem. Soc. Rev. 2014, 43, 4714.S. Abouali, C. H. Yim, A. Merati, Y. Abu-Lebdeh, V. Thangadurai, ACS Energy Lett. 2021, 6, 1920.S. R. Yeandel, B. J. Chapman, P. R. Slater, P. Goddard, J. Phys. Chem. C 2018, 122, 27811.B. Dong, A. R. Haworth, S. R. Yeandel, M. P. Stockham, M. S. James, J. W. Xiu, D. W. Wang, P. Goddard, K. E. Johnston, P. R. Slater, J. Mater. Chem. A 2022, 10, 11172.Y. Yang, H. Zhu, ACS Appl. Energ. Mater. 2022, 5, 15086.M. A. Limpert, T. B. Atwater, T. Hamann, G. L. Godbey, G. T. Hitz, D. W. McOwen, E. D. Wachsman, Chem. Mat. 2022, 34, 9468.Y. X. Guo, J. Cheng, Z. Zeng, Y. Y. Li, H. Q. Zhang, D. P. Li, L. J. Ci, ACS Appl. Energ. Mater. 2022, 5, 2853.S. Lobe, C. Dellen, M. Finsterbusch, H. G. Gehrke, D. Sebold, C. L. Tsai, S. Uhlenbruck, O. Guillon, J. Power Sources 2016, 307, 684.R. Pfenninger, M. Struzik, I. Garbayo, E. Stilp, J. L. M. Rupp, Nat. Energy 2019, 4, 475.

Simultaneous Solid Electrolyte Deposition and Cathode Lithiation for Thin Film Batteries

Interest in thin film solid state lithium-ion batteries (TFSSLIBs) continues to grow because of their increased safety over flammable liquid electrolytes and their compatibility with well-established thin-film fabrication methods and characterization techniques. TFSSLIBs are also attractive for addressing fundamental questions because they generally comprise fewer components (no binders or conductive additives), and are commonly used to investigate the formation and evolution of solid electrode/electrolyte interfaces. TFSSLIBs are well suited to study the inherent capacity retention and rate performance of cathode materials in a symmetric battery structure, e.g., cathode/SSE/cathode. V2O5 is a candidate with a high theoretical capacity and insertion chemistry of up to 3 Li ions per V2O5, but which practically is unable to achieve highly reversible cycling of even Li2V2O5 due to the structural phase change upon lithiation. By designing a TFSSLIB model system with a solid electrolyte that forms a stable electrode/electrolyte interface, e.g. lithium phosphorous oxynitride (LiPON), in a symmetric configuration, we are able to study the performance of LixV2O5 thin film cathodes without the additional deleterious effects related to anode performance.We will discuss the fabrication and cycling performance of two different symmetric V2O5 TFSSLIB configurations. The first is a V2O5/LiPON/LixV2O5 TFSSLIB, where the cyclable lithium in this system is included via simultaneous electrolyte deposition and lithiation of one V2O5 cathode during the RF sputtering process, as discussed in our recent publication.1 The second configuration is an LixV2O5/LiPON/LixV2O5 TFSSLIB where lithium is included during the auto-lithiation step of the first V2O5 electrode as well as during the co-sputtered deposition of the second V2O5 electrode. A comparison of the two TFSSLIB symmetric cell performances will be discussed, as well as a comparison to similar symmetric cells cycled in liquid electrolyte. We show that the deposition of the solid-state electrolyte LiPON onto thin film V2O5 leads to a uniform lithiation of up to 2.2 Li per V2O5, without affecting the Li concentration in the LiPON and its ionic conductivity. In the LixV2O5/LiPON/LixV2O5 system, we demonstrate cycling of >270 mAh/g at a rate of 20C, for 1600 cycles with only 8.4% loss in capacity.1. Warecki, Z. et. al., Simultaneous Solid Electrolyte Deposition and Cathode Lithiation for Thin Film Batteries and Lithium Iontronic Devices, ACS Energy Lett, 2024, 9, 2065-2074

Study on the Phosphate Compound Adsorption onto MgO-KOH/Biochar Adsorbent as Binding Agent in Diffusive Gradient in Thin Film (DGT) Technique for Bioavailable Phosphate Detection

Phosphate compounds, particularly bioavailable forms like PO₄³⁻, are critical contributors to eutrophication. In this study, MgO-KOH/biochar was used as a binding agent in the Diffusive Gradient in Thin Films (DGT) technique to enhance phosphate detection. The adsorbent was synthesized from biochar derived from palm oil waste, activated with KOH to increase surface area, and combined with MgO for enhanced adsorption efficiency. The adsorption process followed a pseudo-second-order kinetic model, indicating that chemical interactions dominated the adsorption mechanism. Under different pH levels and phosphate concentrations, the material showed a good selectivity for orthophosphate, achieving an adsorption capacity of approximately 100 mg/g. Characterization via FTIR, XRD, and SAA confirmed the successful synthesis of MgO-KOH/biochar and its structural properties, which contributed to its performance. Additionally, the MgO-KOH/biochar DGT device demonstrated better efficiency in adsorbing PO₄³⁻ compared to conventional ferrihydrite-based DGT systems, positioning it as a highly effective tool for monitoring bioavailable phosphates in aquatic environments. Copyright © 2024 by Authors, Published by BCREC Publishing Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

New Materials for Thin-Film Solid-Phase Microextraction (TF-SPME) and Their Use for Isolation and Preconcentration of Selected Compounds from Aqueous, Biological and Food Matrices.

Determination of a broad spectrum of analytes, carried out with analytical instruments in samples with complex matrices, including environmental, biological, and food samples, involves the development of new and selective sorption phases used in microextraction techniques that allow their isolation from the matrix. SPME solid-phase microextraction is compatible with green analytical chemistry among the sample preparation techniques, as it reduces the use of toxic organic solvents to the minimum necessary. Over the past two decades, it has undergone impressive progress, resulting in the development of the thin-film solid-phase microextraction technique, TF-SPME (the thin-film solid-phase microextraction), which is characterized by a much larger surface area of the sorption phase compared to that of the SPME fiber. TF-SPME devices, in the form of a mostly rectangular metal or polymer substrate onto which a thin film of sorption phase is applied, are characterized, among others, by a higher sorption capacity. In comparison with microextraction carried out on SPME fiber, they enable faster microextraction of analytes. The active phase on which analyte sorption occurs can be applied to the substrate through techniques such as dip coating, spin coating, electrospinning, rod coating, and spray coating. The dynamic development of materials chemistry makes it possible to use increasingly advanced materials as selective sorption phases in the TF-SPME technique: polymers, conducting polymers, molecularly imprinted polymers, organometallic frameworks, carbon nanomaterials, aptamers, polymeric ionic liquids, and deep eutectic solvents. Therefore, TF-SPME has been successfully used to prepare analytical samples to determine a broad spectrum of analytes in sample matrices: environmental, biological, and food. The work will be a review of the above-mentioned issues.

Catalytically Active Gold Nanoparticles on Star Block Co-polymer Matrix: Synthesis of Nanocomposite Film Exploring the Langmuir-Blodgett Technique.

Nanocomposites with metal nanoparticles and block copolymers distributed in a stable and robust thin film are preferred for various applications. Here, synthesis of such a nanocomposite is reported, which is composed of gold nanoparticles (AuNPs) embedded in a tetronic 701 (T701) and 90R4 (T90R4) thin film matrix generated using the Langmuir-Blodgett (LB) thin film technique. Tetronics contain a monoprotonated central ethylenediamine group at pH 5 due to the presence of chloroauric acid (HAuCl4) in the subphase, along with poly(ethylene oxide) (PEO) and poly(propylene oxide) (PPO) blocks, both of which have the capacity to serve as the reducing agent toward chloroaurate anion (AuCl4-). Calorimetric experiments have shown that T90R4 has a better interaction with AuCl4-, probably due to its better electrostatic interaction with AuCl4- ions due to the higher % of the hydrophilic PEO group. On the other hand, the T701-AuNP interaction turned out to be more spontaneous due to the higher hydrophobicity of T701 (higher PPO/PEO ratio). The optical properties and structure/morphology of these nanocomposites are characterized by UV-vis spectroscopy, FTIR spectroscopy, XRD, and TEM. The composite thin film has the ability to catalyze the organic electron transfer process between p-nitrophenol and p-aminophenol in the presence of sodium borohydride. A clear correlation has been found between the reaction rates and the kind of tetronic present in the nanocomposite, which acted as a matrix and stabilizer toward AuNPs.

Development of a selective COX-2 inhibitor: from synthesis to enhanced efficacy via nano-formulation.

Non-steroidal anti-inflammatory drugs NSAIDs are widely used for managing various conditions including pain, inflammation, arthritis and many musculoskeletal disorders. NSAIDs exert their biological effects by inhibiting the cyclooxygenase (COX) enzyme, which has two main isoforms COX-1 and COX-2. The COX-2 isoform is believed to be directly related to inflammation. Based on structure-activity relationship (SAR) studies of known selective COX-2 inhibitors, our aim is to design and synthesize a novel series of 2-benzamido-N-(4-substituted phenyl)thiophene-3-carboxamide derivatives. These derivatives are intended to be selective COX-2 inhibitors through structural modification of diclofenac and celecoxib. The compound 2-benzamido-5-ethyl-N-(4-fluorophenyl)thiophene-3-carboxamide VIIa demonstrated selective COX-2 inhibition with an IC50 value of 0.29 μM and a selectivity index 67.24. This is compared to celecoxib, which has an IC50 value of 0.42 μM and a selectivity index 33.8. Molecular docking studies for compound VIIa displayed high binding affinity toward COX-2. Additionally, the suppression of protein denaturation with respect to albumin was performed as an indicative measure of the potential anti-inflammatory efficacy of the novel compounds. Compound VIIa showed potent anti-inflammatory activity with 93% inhibition and an IC50 value 0.54 μM. In comparison, celecoxib achieved 94% inhibition with an IC50 value 0.89 μM. Although molecule VIIa demonstrated significant in vitro anti-inflammatory activity, adhered to Lipinski's "five rules" (RO5) and exhibited promising drug-like properties, it showed indications of poor in vivo activity. This limitation is likely due to poor aqueous solubility, which impacts its bioavailability. This issue could be addressed by incorporating the drug in niosomal nanocarrier. Niosomes were prepared using the thin-film hydration technique. These niosomes exhibited a particle size of less than 200 nm, high entrapment efficiency, and an appropriate drug loading percentage. Transmission electron microscopy (TEM) and differential scanning calorimetry (DSC) studies revealed that the niosomes were spherical and demonstrated compatibility of all of its components. The drug release study indicated that the pure drug had limited practicality for in vivo use. However, incorporating the drug into niosomes significantly improved its release profile, making it more suitable for practical use.

Rutin loaded bilosomes for enhancing the oral activity and nephroprotective effects of rutin in potassium dichromate induced acute nephrotoxicity in rats

Rutin, a flavone glycoside, has shown to have a significant beneficial kidney protection effect in drug-induced nephropathy. However, its poor solubility and low oral bioavailability have limited its pharmacological applications. This study aimed at formulating rutin-loaded bilosomes to enhance the renal protective effect of rutin for oral application. Rutin-loaded bilosomes were developed using thin-film hydration technique. The prepared formulations were characterized by entrapment efficiency percentage (EE%), vesicular size (VS) and zeta potential (ZP) measurement. The developed formula exhibited moderate EE%, ranging from 20.02 ± 2.85 to 48.57 ± 3.57%, suitable VS results that ranged from 502.1 ± 36 to 665.1 ± 45 nm and high ZP values (≤ -41.4 ± 7.27 mV). Transmission electron microscopy revealed the spherical shape of the developed bilosomes. The in-vitro release study revealed prolonged release of rutin from bilosomes, relative to free drug. F2, prepared using the molar ratio span 60: cholesterol: sodium cholate 1:1:0.5, was selected for further investigations as it showed the highest EE%, smallest VS, optimum ZP, and persistent release profile. In-vivo studies were performed on drug-induced nephropathy in rats. Acute renal failure was induced using a single dose of potassium dichromate (PDC; 15 mg/kg; i.p). The selected formulation, F2, alleviated kidney dysfunction, oxidative stress and inflammation via decreasing MDA, TNF-α and TGF-β and increasing GSH. In addition, F2 promoted Akt/PI3K activation against PDC-induced acute renal failure. Histopathology results came in accordance with in-vivo results. Thus, bilosomes could be considered a potential delivery system for enhancing the oral delivery and kidney protection activity of rutin.