Wet Chemistry Research Articles

Preparation and Characterization of Perfluoropolyether-Silane@Ethye Cellulose Polymeric Microcapsules.

A novel polymeric microcapsule was designed and synthesized using perfluoropolyether silane (PFPE-silane) as a superhydrophobic core material and ethyl cellulose (EC) as a shell material. The effects of the stirring rate and the core-to-shell ratio on the synthesized microcapsules were investigated. The physicochemical properties of the polymeric microcapsules were evaluated using scanning electron microscopy, fourier transform infrared spectroscopy, thermogravimetric analysis, laser particle size analysis, and wettability analysis. The results showed that when the stirring rate was 650 rpm and the core-to-shell ratio was 1:1, well-distributed and uniformly dispersed microcapsules could be obtained. The results also indicated that the prepared polymeric microcapsules were spherical particles with micropores on the surface, and they had an average particle size of 165.71 μm. The EC shells could effectively prevent the thermal decomposition of PFPE-silane during cement hydration, and the PFPE-silane also exhibited excellent hydrophobicity. The specially designed structure of this polymeric microcapsule suggests its potential for enhancing the corrosion resistance of reinforced concrete structures.

Synergistic green degradation of organic dyes using a BiSI catalyst: Adsorption, sonocatalysis, and photocatalysis

Water contamination due to the uncontrollable release of organic dyes into water bodies poses a serious threat to human health and ecosystems biodiversity. To address the harmful impact caused by these compounds, the development of suitable removal techniques and materials is critical. In this regard, bismuth sulfide iodide (BiSI) emerges as a promising semiconductor for wastewater treatment due to its adsorptive, sonocatalytic, and photocatalytic properties. In this study, BiSI was successfully synthesized via a wet chemistry route at moderate temperatures (120 °C) and employed as catalyst on the degradation of Rhodamine B (RhB). The main purpose addressed in this work was to achieve a synergistic effect between sono- and photocatalysis to improve the performance of the catalyst for the fast and effective removal of organic compounds. The synthesized BiSI was thoroughly characterized including its morphology, structure, surface, and optical properties. The removal capacity of RhB onto BiSI was examined under different operating conditions. BiSI catalyst demonstrated a remarkable efficiency of 95.0 % and a maximum removal capacity (Qmax) of 16.5 mg/g in just 3 min by using single sonocatalysis and photocatalysis. Besides, applying the combined sonophotocatalytic approach, the performance of the BiSI catalyst was significantly enhanced (Qmax of 28.7 mg/g), when simultaneously subjected to ultrasonic waves and ultraviolet (UV) irradiation. In addition, a possible degradation mechanism was proposed. In short, the results achieved in this study effectively demonstrated the synergistic effect when combining sono- and photocatalysis in a single method, and also the suitability of the developed BiSI catalyst for the rapid and effective degradation of RhB, employing a sustainable approach that relies on ultrasound energy and light irradiation.

Arsenate and phosphate adsorption onto Mg-Fe layered double hydroxides: The charge-distribution multisite complexation (CD-MUSIC) modeling as a tool to predict competitive oxyanion behavior

The adsorption of arsenate and phosphate onto natural or synthetic layered double hydroxides (LDHs) has emerged as a promising solution to minimize the environmental effects of these compounds in soils and waters. In the present work, the adsorption of these oxyanions onto Mg-Fe LDHs in both single-ion and competitive systems was studied through wet chemistry experiments, solid-state analyses, and advanced surface complexation modeling (SCM). The Mg-Fe LDH showed a good efficiency to remove both As and P, being the pH of the system a major driver for the adsorption levels observed. Adsorption results for competitive systems showed a decrease for both oxyanions compared to the single-ion adsorption systems. The adsorption behavior is mechanistically described using two types of SCM, namely the diffusion layer model (DLM) and the charge-distribution multisite complexation model (CD-MUSIC). The later model captures better the influence of pH and ionic strength on the adsorption of arsenate and phosphate onto LDH in both single-ion and multicomponent systems. The best description of the experimental results was obtained when combining two types of surface complexes, namely monodentate inner-sphere complex at lower pH values and monodentate outer-sphere complex at higher pH values. This model approach provides more detailed information about the surface properties of LDHs, which may be beneficial for future studies dealing with LDHs as reactive phases influencing metal(loid) mobility in water or soil systems.

Investigating temperature variability on antioxidative behavior of synthesized cerium oxide nanoparticle for potential biomedical application.

Cerium oxide nanoparticles (CNP) have garnered significant attention due to their versatile redox properties and wound-healing applications. The antioxidative nature of CNP is due to its ability to be oxidized and reduced, followed by the capture or release of oxygen which is used for scavenging reactive oxygen species (ROS). Herein, CNP is produced through a wet chemistry approach and its tunable redox property is tested across a range of temperatures. The synthesized CNP was observed to reveal the signature peak at 245nm indicating a high Ce+3/Ce+4 ratio. Towards evaluating the redox antioxidative behavior, CNPs were subjected to a comprehensive analysis for superoxide dismutase mimetic analysis with riboflavin-mediated nitroblue tetrazolium scavenging assay. The results demonstrated that the redox activity of cerium oxide nanoparticles was strongly influenced by the different temperature ranges. Superoxide dismutase mimetic activity was observed to be reduced with a decrease in temperature as we moved from 4°C (80% activity) to -80°C (47% activity) at 1mM conc of CNP. Similarly, the SOD mimetic activity increased with an increase in temperature from 40°C (72% activity) to 70°C (94% activity). Further, CNP was found to inhibit E. coli (gram+ve) and Enterobacter (gram-ve) beyond 70% simultaneously at 1mM conc, indicating its potential application as a remarkable antimicrobial agent. CNP also inhibited the alpha-amylase activity up to the 60% at 1mM conc suggesting its potential application in antidiabetic wound healing therapy. Overall, the CNP finds its application in mitigating the oxidative stress-related disorder exhibited by its high antioxidative, antimicrobial, and antidiabetic behavior.

Incorporation of U(IV) in monazite-cheralite ceramics under oxidizing and inert atmospheres.

This work is the first attempt to prepare Nd1-xCaxUxPO4 monazite-cheralite with 0 < x ≤ 0.1 by a wet chemistry method. This method relies on the precipitation under hydrothermal conditions (T = 110 °C for four days) of the Nd1-xCaxUxPO4·nH2O rhabdophane precursor, followed by its thermal conversion for 6 h at 1100 °C in air or Ar atmosphere. The optimized synthesis protocol led to the incorporation of U and Ca in the rhabdophane structure. After heating at 1100 °C for 6 h in air, single-phase monazite-cheralite samples were obtained. However, α-UP2O7 was identified as a secondary minor phase in the samples heated under Ar atmosphere. The U speciation in the samples converted in an oxidising atmosphere was carefully characterized using synchrotron radiation by combining HERFD-XANES and XRD. These results showed the presence of a minor secondary phase containing hexavalent uranium and phosphate with a stoichiometry of U : P = 0.78. This highly labile uranyl phosphate phase incorporated 21 mol% of the uranium initially precipitated with the rhabdophane precursor. This phase was completely removed by a washing protocol. Thus, single-phase monazite-cheralite was obtained through the wet chemistry route described in this work with a maximum U loading of x = 0.08.

Colloidal quantum dot materials for next-generation near-infrared optoelectronics.

Colloidal quantum dots (CQDs) are a promising class of materials for next-generation optoelectronic devices, such as displays, LEDs, lasers, photodetectors, and solar cells. CQDs can be obtained at low cost and in large quantities using wet chemistry. CQDs have also been produced using various materials, such as CdSe, InP, perovskites, PbS, PbSe, and InAs. Some of these CQD materials absorb and emit photons in the visible region, making them excellent candidates for displays and LEDs, while others interact with low-energy photons in the near-infrared (NIR) region and are intensively utilized in NIR lasers, NIR photodetectors, and solar cells. In this review, we have focused on NIR CQD materials and reviewed the development of CQD materials for solar cells, NIR lasers, and NIR photodetectors since the first set of reports on CQD materials in these particular applications.

A scalable fabrication method for gold nanodisk-upconverting nanoparticle hybrid nanostructures.

Plasmonic nanostructures can be used to enhance the efficiency of upconversion nanoparticles (UCNPs) and enable new functionalities. However, the fabrication of these hybrid plasmon-UCNP nanostructures has traditionally relied on either wet chemistry or nanolithography routes that are difficult to control, scale up, or both. In this work, we present a scalable nanofabrication process, capable of producing a massive array of gold-UCNP hybrid nanostructures over a few mm2 area and with excellent uniformity in the photoluminescence intensity. This new approach combines the scalability of the bottom-up self-assembly method and the precision of the top-down nanolithography approach. It provides an efficient alternative route for the production of plasmonically enhanced UCNPs. A detailed discussion on the optimization of the UCNP self-assembly, the gold nanodisk lithography, and the nanopattern transfer processes is presented here. Additionally, we showcase the potential of this new approach for fabricating mechanical force sensors based on the selective plasmonic enhancement of the UCNP emission. This new approach holds great potential in facilitating the production of plasmonically enhanced UCNPs that can be deployed for both imaging and sensing applications.

Enhanced hydrogen storage property of MgH2 caused by a BaCrO4 nanocatalyst.

Magnesium hydroxide (MgH2) has a broad application prospect in solid hydrogen storage, but the associated higher dehydrogenation temperature and undesirable cycling capacity limit its large-scale application. In this study, a BaCrO4 nanocatalyst prepared via a wet chemistry method was added to MgH2 to achieve better kinetic and thermodynamic performances. Kinetic tests suggested that the onset hydrogen desorption temperature was decreased for milled MgH2 from 390 °C to below 280 °C after the introduction of a 5 wt% BaCrO4 nanocatalyst and the maximum dehydrogenation amount was up to 6.32 wt%. With regard to hydrogen absorption, MgH2 incorporated with 10 wt% BaCrO4 could fully absorb 5.78 wt% H2 within 10 min at 300 °C and recharge 3.1 wt% H2 at a low temperature of 250 °C. In comparison, the hydrogen uptake amounts for MgH2 under the same conditions were only 3.98 wt% and 1.52 wt%. With regard to hydrogen desorption, 5 wt% BaCrO4-modified MgH2 could discharge 4.25 wt% H2 within 10 min at 325 °C and 4.81 wt% H2 at 300 °C, while MgH2 could not dehydrogenate at 300 °C. Meanwhile, only 5% of the performance decayed for 5 wt% BaCrO4-modified MgH2 during ten cycles. Dehydrogenation E a reduced to 106.75 kJ mol-1 in contrast to 156.55 kJ mol-1 for MgH2. In addition, DFT results verified that the BaCrO4 nanocatalyst reduced the band gap from 2.78 eV to 2.16 eV to improve the thermodynamic property of MgH2 and contributed to the decrease in the dehydrogenation energy barrier from 2.27 eV to 1.54 eV. This work provides an insight into the performance of ternary transition metal nanocatalysts for MgH2 hydrogen storage systems.

Mechanical and antibacterial properties of FDM additively manufactured PLA parts

This study explores the compression and antibacterial properties of 10x10 × 10 mm polylactic acid (PLA) cubes manufactured through FDM additive printing for biomedical parts. A 3x3 full factorial DOE with 3 replicates examines the impact of printing parameters (infill %, print speed, and layer height). The highest compression strength and stiffness recorded were 91 MPa and 0.76 GPa, respectively. Despite minor mass variations (1.05 ± 0.09 g) under all the investigated parameters, the mean strength of all printed parts was 67.6 ± 10.6 MPa, highlighting the significant influence of processing parameters on mechanical properties. Heat treatment at 60 °C for 30 min improved stiffness. Investigation of various parameters, including layer height and orientation, revealed that larger layer heights resulted in reduced compression strength. Anisotropic compression properties persisted post-heat treatment due to thermal stresses and interlayer bonding. The flat direction (top view) exhibited higher compression properties due to a homogeneous microstructure, minimized interlayer bonding impact, and increased crystallinity. Antibacterial properties against E.coli were induced via coating with peanut-shaped copper nanoparticles (68–267 nm). Nanoparticles were fabricated via a combination of wet chemistry and laser ablation.

Plasma Cleaning of Hydrocarbon and Carbon Contaminated Surfaces of Accelerator Components

To achieve the vacuum quality required for the operation of particle accelerators, the surface of the vacuum vessels must be clean from hydrocarbons. This is usually achieved by wet chemistry processes, e.g., degreasing chemical baths that, in case of radioactive vessels, must be disposed accordingly. An alternative way exploits the oxygen plasma produced by a downstream RF plasma source. This technique offers the possibility of operating in-situ, which is an advantageous option to avoid the handling of voluminous and/or fragile components and a more sustainable alternative to large volume disposable baths. In this work, we test a commercial plasma source in dedicated vacuum systems equipped with quartz crystal microbalances (QCMs). The evolution of the etching rates of amorphous carbon (a-C) thin films deposited on the QCMs to mimic contamination are studied as function of operating parameters. We present the results of the plasma cleaning process applied to the real case of a hydrocarbons-contaminated large vacuum vessel. The studies are complemented by transport simulations and surface contamination monitoring by X-ray photoelectron spectroscopy (XPS) analysis. The evaluation of the vessel cleanliness, which is performed via residual gas analysis (RGA) measurements, is based on CERN’s outgassing acceptance criteria and agrees with both simulations and XPS results.

Portable X-ray fluorescence spectrometry: a cost-effective method for analysing trace metals in deposited dust.

For projects requiring extensive environmental sampling and rapid decision-making to identify trace metal contamination using dust wipes, the cost and time required for wet chemistry analysis can be prohibitive. Under such circumstances there is a need for a suitable screening method that is cost-effective, efficient, and portable. To address this need, this study investigated the utility of portable X-ray fluorescence (pXRF) for the analysis of trace metals in dust wipes. Here, 316 dust wipe samples from three different geographical settings co-located with mining and smelting operations were investigated for their trace metal loadings (μg m-2) of arsenic (As), chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn) using pXRF. Results collected using pXRF were compared against inductively coupled plasma mass spectrometry (ICP-MS) concentrations using matched dust wipes (n = 87) to assess reproducibility. A subset of dust wipes (n = 4) were subject to different pXRF analytical scenarios (ranging from 1 to 12 pXRF measurements) using a standardised test duration of 30 seconds to identify the most efficient number of tests for analytical precision. Conducting four pXRF tests on a single wipe (total exposure time of 120 seconds) returned comparable results to ICP-MS and was adopted for analysis of all samples. Results from dust wipes analysed with both ICP-MS and pXRF (n = 87) showed moderate to strong Spearman Rho correlations (rs = 0.489-0.956, p < 0.01) and linear regression coefficients of variation demonstrated good agreement between methods (R2 = 0.432-0.989, p < 0.05). Linear regression equations were used to correct pXRF data to the ICP-MS dust wipe data for samples analysed by both approaches, and applied to pXRF data that were not subject to ICP-MS analysis (n = 229). Application of the correction formula resulted in a substantial improvement of pXRF's accuracy and precision, confirming its effectiveness for assessing trace metals in dust wipes.

Facile, green and scalable synthesis of single-layer manganese dioxide nanosheets and its application for GSH and cTnI colorimetric detection.

Manganese dioxide (MnO2) nanosheets possess unique physical and chemical properties, making them widely applicable in various fields, such as chemistry and biomedicine. Although MnO2 nanosheets are produced using bottom-up wet chemistry synthesis methods, their scale is below the gram level and requires a long processing time, restricting their effective scale-up from laboratory to market. We report a facile, green and scalable synthesis of MnO2 nanosheets by mixing Shiranui mandarin orange juice and KMnO4 for 30 minutes. We produced more than one gram (1.095) of MnO2 nanosheets with a 0.65 nm mean thickness and a 50 nm mean lateral size. Furthermore, we established a visual colorimetric biosensing strategy based on MnO2 nanosheets for the assay of glutathione (GSH) and cardiac troponin I (cTnI), offering high sensitivity and feasibility in clinical samples. For GSH, the limit of detection was 0.08 nM, and for cTnI, it was 0.70 pg mL-1. Meanwhile, the strategy can be used for real-time analysis by applying a smartphone-enabled biosensing strategy, which can provide point-of-care testing in remote areas.

Теплопроводность керамических композитов YAG:Nd + Mo, полученных методом электроимпульсного плазменного спекания

The microstructure and thermophysical properties (specific heat capacity, thermal conductivity coefficient, heat conductivity coefficient) of fine-grained ceramic composites based on yttrium-aluminum garnet Y2.5Nd0.5Al5O12 (YAG:Nd) with different molybdenum content (10, 20, 40 vol. %) are investigated. Submicron Y2.5Nd0.5Al5O12 powders are obtained by co-precipitation method. Powder compositions of YAG:Nd + Mo with the structure “YAG:Nd core – Mo shell” were obtained using wet chemistry techniques and precipitation of the metal phase from salt solutions. Ceramic composite samples were obtained by the Spark Plasma Sintering (SPS) method. The microstructure and phase composition of ceramics were investigated by electron microscopy and X-ray diffraction phase analysis. YAG:Nd + Mo composites have a high relative density (98.1 – 99 %) and a homogeneous fine-grained microstructure with a grain size of 2 – 3 μm. Increased thermal conductivity and heat conductivity of composites is provided with a content of at least 20 vol.% Mo. For composites with 20% and 40% Mo, the heat conductivity coefficient at 1100 °C reaches 7.0 and 8.8 W⋅m–1⋅K–1, respectively. Sintered composites YAG: Nd + Mo at room temperature and elevated temperatures (up to 1100 °C) have a high heat conductivity coefficient, exceeding the heat conductivity coefficient of uranium dioxide UO2. This makes it possible to use ceramics YAG:Nd+Mo as heat-resistant inert fuel matrices.

Silver nanoclusters stabilized with PVP-BSA conjugate: Optical properties approach

&lt;abstract&gt; &lt;p&gt;The objective of this research was to synthesize fluorescent silver nanoclusters (NC Ag-BSA/PVP) using polyvinylpyrrolidone polymer (PVP) as a stabilizer in conjunction with bovine serum albumin protein (BSA). The nanoclusters were prepared using a wet chemistry reduction technique with two distinctive pathways: the addition of PVP after BSA and the addition of PVP after the metal precursor. The optical properties of the materials were studied in samples with different BSA/PVP molar ratios and varying amounts of metal/reductant. The impact of protein and polymer amounts on fluorescence was determined. The materials were characterized using X-ray diffraction (XRD), infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), X-ray energy dispersive spectroscopy (EDS), dynamic light scattering (DLS), fluorescence spectroscopy, and UV-Vis-NIR spectroscopy.&lt;/p&gt; &lt;p&gt;It was observed that increasing the BSA/PVP ratio resulted in higher fluorescence intensity at λ = 450 nm and a decrease at λ = 600 nm. Regarding the metal/reductant ratio, the amount of metal ions impacted the intensity obtained at λ = 600 nm. The experiments revealed that BSA had the largest effect on fluorescence intensity at λ = 450 nm, with little effect on fluorescence intensity regardless of the amount of polymer used. Due to its one-step synthesis and favorable reaction conditions, the NC Ag-BSA/PVP obtained under the proposed methodology holds promise as an optical marker material. The use of the stabilizing duo BSA-PVP, as well as the proposed amounts in this research, serves as a precedent for developing new experimental syntheses of colloidal nanoparticles.&lt;/p&gt; &lt;/abstract&gt;

Predicting ruminal degradability and chemical composition of corn silage using near-infrared spectroscopy and multivariate regression.

The aim of this study was to develop and validate regression models to predict the chemical composition and ruminal degradation parameters of corn silage by near-infrared spectroscopy (NIR). Ninety-four samples were used to develop and validate the models to predict corn silage composition. A subset of 23 samples was used to develop and validate models to predict ruminal degradation parameters of corn silage. Wet chemistry methods were used to determine the composition values and ruminal degradation parameters of the corn silage samples. The dried and ground samples had their NIR spectra scanned using a poliSPECNIR 900-1700 model NIR sprectrophotometer (ITPhotonics S.r.l, Breganze, IT.). The models were developed using regression by partial least squares (PLS), and the ordered predictor selection (OPS) method was used. In general, the regression models obtained to predict the corn silage composition (P>0.05), except the model for organic matter (OM), adequately estimated the studied properties. It was not possible to develop prediction models for the potentially degradable fraction in the rumen of OM and crude protein and the degradation rate of OM. The regression models that could be obtained to predict the ruminal degradation parameters showed correlation coefficient of calibration between 0.530 and 0.985. The regression models developed to predict CS composition accurately estimated the CS composition, except the model for OM. The NIR has potential to be used by nutritionists as a rapid prediction tool for ruminal degradation parameters in the field.

Reducing Occupational Risks and Greening a Traditional Sample Treatment of Industrial Fluorine Containing-materials by Application of Design of Experiments

Despite the new technological advances, some traditional methodologies concerning wet chemistry must be used as reference methods when dealing with complex matrices or when no certified reference materials are available. In this context, Willard-Winter distillation is nowadays still employed as a reference technique for fluorine extraction in day-to-day analysis. However, this procedure requires strong acid mixtures, increasing waste treatment procedures/costs and the potential risks associated with their use. The present work reports the application of design of experiments (DoE) to improve the analytical methodology of reference for fluorine extraction through Willard-Winter distillation by substituting perchloric acid. Variables affecting the sample treatment of fluorine-containing compounds, anhydrite, fluorspar, cryolite and aluminium fluoride were studied to ensure complete dissolution and total extraction of fluorine. Volume of sulfuric acid, sample amount, volume of distilled solution including volume of melt and amount of NaOH for fluorspar and the extended fluoroaluminate compounds were the variables studied. Predicted experimental conditions were performed and validated in the target compound, obtaining fluorine concentrations comparable to those obtained by the reference methodology. By this modified approach, not only harmful effect of manipulation of perchloric acid is reduced but also costs of the analytical procedure do so. Besides, a greener performance is achieved by avoiding chlorinated species, reducing waste dangerousness and its treatment.

New 5-alkyl-1,2,4-triazole-3-thione surfactants with antifungal and silver nanoparticles stabilization activity

New 5-alkyl-1,2,4-triazole-3-thiones containing structural fragments of anionic surfactants have been synthesized and examined as stabilizers in the wet chemistry synthesis of silver nanoparticles (AgNPs). The synthesis of the new 1,2,4-triazole-3-thiones was done via the cyclization reaction of 4-acyl-thiosemicarbazides in basic conditions. The structure of the new surfactant was analyzed by spectroscopic (infrared and nuclear magnetic resonance) and theoretical DFT methods. The surface activity characteristic, such as critical micelle concentration, was estimated using the conductivity method and the 1H NMR technique. The structural peculiarities of the new compounds testify to their surfactant properties, which is why they were explored as stabilizers in the chemical synthesis of silver nanoparticles from silver nitrate in an aqueous solution. The UV–VIS spectroscopy technique confirmed the formation of AgNPs in aqueous solutions of 5-alkyl-1,2,4-triazole-3-thiones. The stable AgNPs were obtained only using 1,2,4-triazole-3-thiones with longer alkyl chains (pentadecyl and heptadecyl), whereas the 5-pentyl-1,2,4-triazole-3-thione and the 5-heptyl-1,2,4-triazole-3-thione have not shown considerable stabilization activity. To better understand the interaction of the 1,2,4-triazole-3-thiones with AgNPs, Raman spectra analysis, quantum chemical modeling, and force field molecular dynamics were performed. The new triazoles were studied for their antifungal activity by the determination of minimal inhibition concentrations and docking studies.

Agreement of results between dry and wet chemistry system for common clinical chemistry parameters

Agreement of results between dry and wet chemistry system for common clinical chemistry parameters

Thermo-responsive polymer-based Janus biogenic-nanosilica composite, part B: Experimental study as a multi-functional synergistic shale stabilizer for water-based drilling fluids

Wellbore instability caused by shale swelling and dispersion has always been a thorny issue for drilling complex formations. Nanotechnology has offered a revolutionary solution for shale stabilization in water-based drilling fluids (WBDFs). Recent technological advancement in nanomaterials for optimal performance using economically and environmentally sustainable pathway is an utmost desire in oil and gas industries. In this research, Janus nanocomposite (TRJN) with rice husk (RH)-extracted biogenic nanosilica core (RH-NSP) having the shell integrating synergistic benefits of thermo-responsive and amino-based materials, which was reported in our previous work was assessed as a novel shale stabilizer in drilling fluids. The product is anticipated to simultaneously improve the chemical inhibition and nanoplugging performances in shaly formations. TRJN was assessed as an additive in WBDF in comparison with symmetrical thermo-responsive polymer-based nanocomposite (TRN) counterpart and parent RH-NSP. Results from the rheological test revealed that, albeit both nanocomposites (i.e., TRN and TRJN) could provide a certain rheological control above the LCST compared to RH-NSP, but TRJN-blended fluid was less sensitive to increasing temperatures. The inhibitory effects were investigated based on cuttings hot rolling recovery rate, linear swelling rate, pressure penetration rate, tensile strength of shale reduction rate, and high temperatures and high pressures filtration loss. TRJN demonstrated higher chemical inhibition compared to RH-NSP and TRN, driving a better capacity to control pressure penetration. The higher mean free energy of TRJN/Na-Mt (sodium montmorillonite) system than TRN/Na-Mt system was an indication of its stronger interactions with Na-Mt particle, which triggered changes in microstructures, considering the results of zeta potential, FT-IR, surface wettability, X-ray diffraction, and SEM analyses. This, therefore contributing to firmly trap the TRJN into the multi-scale pore structure of the shale and beneficially promoted the construction of a tight hydrophobic plugging layer over the shale surface from the outward face. Lastly, the synergistic enhancement mechanisms of shale inhibition with TRJN was further proposed.

Optimization of Laser-Induced Graphene Electrodes for High Voltage Micro-Supercapacitors

With the development of grid-based distributed sensing with low-power electronics, the need for delocalized power supplies, Energy Storage Devices (ESDs) are moving toward miniaturized scales. Among ESDs, micro-supercapacitors (µSC) are currently under development as an alternative or complementary power supply/backup to batteries. Laser-induced graphene (LIG) is an emerging technology based on the laser conversion of polymers into graphene-based conductive materials. Polyimide (PI) is the most investigated polymer, moreover, it finds several applications in the electronics field. Laser scribing of polymers fastens the device processing reducing the number of wet chemistry steps carried out to fabricate micro-devices.PI Kapton foils of 125 µm thickness were used as substrate materials to produce LIG samples. A CO2 laser was exploited to convert polymeric samples and to pattern hard masks to print devices of optimized geometry and material properties. Further, electrodeposition processes can be used to increase the material capacity by depositing transition metal oxides with pseudocapacitive features. Among them, maganese oxide can be electrodeposited anodically without recurring to any thermal step. Tuning the LIG storage mechanism, and combining them, allows several degrees of freedom to design devices able to work in organic electrolyte environments in voltage windows ranging from 2.5 V up to 4.5 V. Moreover, optimization of electrode charges allows for improving the overall device lifetime and energetic efficiency.