Efficient Electron Transfer Research Articles

Development of CuFe2O4 microspheres/carbon sheets composite materials as a sensitive electrochemical sensorfor determination of bisphenol A.

A composite material based on CuFe-ZIF-derived CuFe2O4 nano-microspheres grown in situ and well-ordered on carbon sheets (CS) was prepared and applied for highly effective determination of bisphenol A (BPA). The composite material possessed inherently high redox activity due to the presence of both Cu and Fe ions with various oxidation states (Cu²⁺/Cu⁺ and Fe³⁺/Fe²⁺), high specific surface area, uniform distribution of Cu and Fe ions, and a robust framework imparted by its precursor CuFe-ZIF. Thisled to increased active sites for electrochemical reactions, improved electron transfer efficiency, and structural integrity during electrochemical cycling. Furthermore, combining CS with CuFe2O4 not only provided a large surface area to support well-ordered CuFe₂O₄ nano-microspheres without aggregation, but also enhanced the conductivity and mechanical stability of the CuFe₂O₄/CS composite. This results in synergistic effects that enhanced the overall performance of the composite material. In addition, both copper and iron are relatively non-toxic and abundant, making CuFe₂O₄/CS safe and cost-effective for large-scale applications. Consequently, the CuFe2O4/CS-modified electrode shows highly efficient electrochemical sensing properties with a wider detection range of 0.009-168 µM and lower detection limit of 0.0027 µM (S/N = 3) compared withmost reported BPA sensors. It also hasanoptimized current at pH 7 which is convenient for real world applications. This CuFe2O4/CS modified electrode as a highly sensitive electrochemical platform can be applied to monitor BPA concentrations in bottled water with good recovery (97.2-102.2%).

Chromium(VI) and Nitrate Removal from Groundwater Using Biochar-Assisted Zero Valent Iron Autotrophic Bioreduction: Enhancing Electron Transfer Efficiency and Reducing EPS Accumulation.

Current strategies primarily utilize heterotrophic or mixotrophic bioreduction for the simultaneous removal of Cr(VI) and NO3- from groundwater. However, given the oligotrophic nature of groundwater, autotrophic bioreduction could be more appropriate, though it remains notably underdeveloped. Here, an autotrophic bioreduction technology utilizing biochar (BC)-assisted zero valent iron (ZVI) is proposed. The pyrolysis temperature of BC was optimized to enhance electron transfer efficiency and reduce extracellular polymeric substances (EPS) accumulation. BC500, with the superior electron transfer capabilities, was the most effective. After an 11-week period, the ZVI+BC500 biotic column still achieved 100% removal efficiency for Cr(VI) and 93.37±0.33% for NO3-, with initial concentrations of 26 mg/L and 50 mg/L, respectively. Its performance significantly surpasses that of ZVI alone, effectively reducing the interference of Cr(VI) on denitrification. The presence of quinone and phenolic compounds in BC500, serving as electron-accepting and electron-donating groups, improves the efficiency of electron transfer between ZVI and microbes. Metagenomic analysis showed an increase in the growth of autotrophic bacteria such as Hydrogenophaga spp. and Rhodanobacter denitrificans, and heterotrophic bacteria including Arenimonas daejeonensis and Chryseobacterium shandongense. The promotion facilitates the expression of genes associated with Cr(VI) reduction (chrR, nemA) and denitrification (narG, nirS). BC500 also enhanced EPS production, which facilitates the adsorption and reduction of Cr(VI), mitigating its inhibitory effects on denitrification. Notably, in the ZVI+BC500 biotic column, the accumulated EPS primarily consists of loosely bound EPS rather than tightly bound EPS, potentially reducing the risk of pore clogging during in-situ groundwater treatment.

Atomic catalysis meets heterostructure synergy: Unveiling the trifunctional efficacy of transition Metal@WS2/ReSe2

Integrating and advancing renewable energy storage and conversion technologies such as water splitting and rechargeable air-based batteries face significant challenges in finding appropriate catalysts that offer both high activity and low cost. This paper successfully designed efficient, cost-effective, and eco-friendly catalysts that meet the requirements for hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and oxygen reduction reaction (ORR) catalytic activity by employing two-dimensional (2D) transition metal dichalcogenides (TMDs) interface engineering combined with a single-atom doping strategy. First, the heterostructure was constructed, and its optimal layer spacing (3.13 Å) was determined by calculating the most negative binding energy. These materials were theoretically evaluated using density functional theory (DFT), demonstrating that transition metal (TM) can all be firmly attached to the S1 site of the WS2/ReSe2 Z-scheme heterostructure with favorable binding energies and excellent electronic properties. By comparing the catalysts doped with different metals (Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn), the three functional catalysts with the best performance were finally selected: Mn@WS2/ReSe2, Ni@WS2/ReSe2, and Cu@WS2/ReSe2. In particular, Mn@WS2/ReSe2 exhibited exceptional promise as multifunctional catalysts, with overpotentials for the HER/OER/ORR of 0.05/0.29/0.35 V, respectively. The superior catalytic performance of this WS2/ReSe2 Z-scheme heterostructure was attributed to the introduction of TM atoms and the synergistic interaction between rhenium and the TM atoms. This interaction facilitated more efficient electron transfer between the catalyst and the reactants, enhancing the overall catalytic activity. This research is a successful attempt to combine interface engineering with single-atom catalysis (SACs). It provided valuable insights into the design of next-generation multifunctional electrocatalysts, offering a novel approach to address the growing energy demands in an environmentally benign and economically viable way.

A Supramolecular Wire Able to Self‐Assemble on Gold Surface: Controlling the Film Length to Optimize the Device Lifetime and Electron Transfer Efficiency

AbstractA chemical “lego nanoset” has been used to realize different structures on gold surfaces. Three building blocks have been designed, in order to chemically link the surface and self‐assemble in an ordered manner. Self‐assembled films are arranged on a gold surface into 3D suprastructures via consecutive deposition of different mono‐layers, taken together by thymine‐adenine hydrogen bonds. Three films, composed of one, two, and three helical peptide layers, both containing a zinc‐tetraphenylporphyrin dye as an external sheet, are built and characterized by spectro‐electrochemical and spectroscopic techniques. All films are found to generate current under illumination, and their photoresponse and stability are studied as a function of the number of peptide layers. The efficiency of the photoconversion process has been correlated to the molecular organization of the porphyrin dyes in the film and to the templating role of the bridge between the porphyrin and the gold surface.

Mn−Ce Symbiosis: Nanozymes with Multiple Active Sites Facilitate Scavenging of Reactive Oxygen Species (ROS) Based on Electron Transfer and Confinement Anchoring

AbstractRegulating appropriate valence states of metal active centers, such as Ce3+/Ce4+ and Mn3+/Mn2+, as well as surface vacancy defects, is crucial for enhancing the catalytic activity of cerium‐based and manganese‐based nanozymes. Drawing inspiration from the efficient substance exchange in rhizobia‐colonized root cells of legumes, we developed a symbiosis nanozyme system with rhizobia‐like CeOx nanoclusters robustly anchored onto root‐like Mn3O4 nanosupports (CeOx/Mn3O4). The process of “substance exchange” between Ce and Mn atoms—reminiscent of electron transfer—not only fine‐tunes the metal active sites to achieve optimal Ce3+/Ce4+ and Mn3+/Mn2+ ratios but also enhances the vacancy ratio through interface defect engineering. Additionally, the confinement anchoring of CeOx on Mn3O4 ensures efficient electron transfer in catalytic reactions. The final CeOx/Mn3O4 nanozyme demonstrates potent catalase‐like (CAT‐like) and superoxide dismutase‐like (SOD‐like) activities, excelling in both chemical settings and cellular environments with high reactive oxygen species (ROS) levels. This research not only unveils a novel material adept at effectively eliminating ROS but also presents an innovative approach for amplifying the efficacy of nanozymes.

Enhancing Efficiency and Stability of Inverted Perovskite Solar Cells through Solution‐Processed and Structurally Ordered Fullerene

AbstractThe electron transporting layer (ETL) used in high performance inverted perovskite solar cells (PSCs) is typically composed of C60, which requires time‐consuming and costly thermal evaporation deposition, posing a significant challenge for large‐scale production. To address this challenge, herein, we present a novel design of solution‐processible electron transporting material (ETM) by grafting a non‐fullerene acceptor fragment onto C60. The synthesized BTPC60 exhibits an exceptional solution processability and well‐organized molecular stacking pattern, enabling the formation of uniform and structurally ordered film with high electron mobility. When applied as ETL in inverted PSCs, BTPC60 not only exhibits excellent interfacial contact with the perovskite layer, resulting in enhanced electron extraction and transfer efficiency, but also effectively passivates the interfacial defects to suppress non‐radiative recombination. Resultant BTPC60‐based inverted PSCs deliver an impressive power conversion efficiency (PCE) of 25.3 % and retain almost 90 % of the initial values after aging at 85 °C for 1500 hours in N2. More encouragingly, the solution‐processed BTPC60 ETL demonstrates remarkable film thickness tolerance, and enables a high PCE up to 24.8 % with the ETL thickness of 200 nm. Our results highlight BTPC60 as a promising solution‐processed fullerene‐based ETM, opening an avenue for improving the scalability of efficient and stable inverted PSCs.

Distinguishing Inner and Outer-Sphere Hot Electron Transfer in Au/p-GaN Photocathodes.

Exploring nonequilibrium hot carriers from plasmonic metal nanostructures is a dynamic field in optoelectronics, with applications including photochemical reactions for solar fuel generation. The hot carrier injection mechanism and the reaction rate are highly impacted by the metal/molecule interaction. However, determining the primary type of reaction and thus the injection mechanism of hot carriers has remained elusive. In this work, we reveal an electron injection mechanism deviating from a purely outer-sphere process for the reduction of ferricyanide redox molecule in a gold/p-type gallium nitride (Au/p-GaN) photocathode system. Combining our experimental approach with ab initio simulations, we discovered that an efficient inner-sphere transfer of low-energy electrons leads to an enhancement in the photocathode device performance in the interband regime. These findings provide important mechanistic insights, showing our methodology as a powerful tool for analyzing and engineering hot-carrier-driven processes in plasmonic photocatalytic systems and optoelectronic devices.

Enhanced anaerobic reduction of nitrobenzene under hypersaline fluctuation: Glycine betaine metabolism and microbial osmoadaptation mechanisms

High salinity, particularly large fluctuations in salinity, poses a significant threat to the biological treatment of high-salt industrial wastewater, while glycine betaine (GB) is commonly used for osmotic pressure balance. However, the GB metabolism mechanism and the effect of GB addition on microbial osmoadaptation responding to salt perturbations are still unclear. This study investigated the effect of GB on the stability of anaerobic process in nitrobenzene reduction under various salt perturbations and further explored the microbial osmoadaptation and metabolism mechanism. The nitrobenzene reduction was observably improved with GB addition (R+), and the microbial resilience increased due to repeated salt shocks. The generation of acetic acid showed a 46.21 % decrease in R+ compared to that without GB addition (R-) at 3 % salinity. Meanwhile, the intracellular GB concentration reached 10.76 mg L−1 to 54.76 mg L−1 with salinity increasing from 1.5 % to 6 %. 16S rRNA analysis revealed that the osmoadaptation period was shortened in R+ through the rapid osmoadaptation of salt-intolerant microorganisms (such as Propionibacteriaceae and SBR1031) and the massive enrichment of salt-tolerant microorganisms (such as Glutamicibacter). Besides, the resistance to hypersaline disturbance improved by the increasing size and complexity of the microbial community network. Moreover, the metagenomic analysis revealed that the abundance of genes involved in microbial metabolism was significantly enhanced in R+, indicating a more efficient metabolic efficiency and electrons transfer with GB addition under high-salt environments. This study provides vital insights into GB metabolism and microbial osmoadaptation responding to salt perturbations in long-term high-salt wastewater biotreatment.

Cu-S-Mo Interfacial Sites in CuO2@MoS2/PLLA Scaffolds for Robust Synergistic Antibacterial Efficacy via CDT and PTT

Bacterial infections considerably limit the success of scaffold transplantation. CuO2 may generate hydroxyl radicals through a self-cascade catalytic process, which is effective for sterilization. However, reducing CuO2-derived Cu+ ions to Cu° can lead to a decline in catalytic activity. To overcome these limitations, we anchored CuO2 onto MoS2 to establish stable Cu-S-Mo interfacial sites. The CuO2/MoS2 nanozyme was fabricated using a low-temperature co-precipitation technique and introduced into poly-L-lactic acid scaffolds using selective laser sintering. The Cu-S-Mo interfacial sites showed a triad of functions that synergistically enhanced catalytic performance. These sites stabilized the Cu atoms, augmented catalytic activity by facilitating efficient electron transfer through the Mo4+/Mo6+ redox couple, and improved the conduction of heat derived from the photothermal response of MoS2 to the Cu catalyst. The synergistic action of chemodynamic and photothermal therapy, mediated by the Cu-S-Mo sites, resulted in remarkable antibacterial efficacy, with 92.3% and 93.5% inhibition rates against Staphylococcus aureus and Escherichia coli, respectively. Experimental evidence and simulations demonstrated that Cu-S-Mo structure stabilized the Cu atoms and improved electron transfer via interatomic charge transfer. These results highlight the potential of the CuO2@MoS2/PLLA scaffold in eliminating bacterial infections.

A comprehensive Investigation of Donor-Acceptor anthraquinone derivatives as Versatile and efficient photosensitizers for Dye-Sensitized solar cells

A new metal-free anthraquinone donor–acceptor-π-anchor (D-A-π-A) design was developed using unsymmetrically substituted anthraquinone (ATQ) derivatives functionalized with bromine (Br), diphenylamine (DPA), indoline (Ind), BrATQBzOH, DPAATQBzOH, and IndATQBzOH. The synthesised compounds, functionalized with an anchor group (ethynylbenzoic acid), were evaluated in practical dye-sensitised solar cell, DSSC, devices with the aiming to improve electron injection efficiency. Their properties and applicability were analysed and rationalised based on their energy levels and parameters derived from the current–voltage (I-V) curve analysis in real devices. Femtosecond transient absorption measurements of the sensitiser IndATQBzOH with TiO2 revealed distinct excited state dynamics and charge transfer properties, highlighting the influence of the semiconductor interface. In addition, Density Functional Theory (DFT) and Time-Dependent DFT (TDDFT) electronic quantum calculations were performed, which revealed that the new anthraquinone-based dyes exhibit optimal coplanarity for efficient electron transfer, with their LUMO and HOMO energy levels facilitating electron injection into TiO2. In contrast to the low efficiencies found for previous anthraquinone derivatives, with maximum photocurrent efficiencies (PCE) below 0.2%, 9,10-anthraquinone derivatives were used as acceptors attached to suitable donors (DPA or Ind), and PCE above 1% were obtained.

Enhanced adsorption and reduction of Pb(II) from aqueous solution by sulfide-modified nanoscale zerovalent iron: characterization, kinetics and mechanisms

Nanoscale zerovalent iron (nZVI) was prone to aggregation and passivation, which limited its application. Here, sulfide-modified nZVI (S-nZVI) was synthesized to enhance Pb(II) removal, the transmission electron microscope and scanning electron microscope showed S-nZVI particles exhibited a core–shell structure, with Fe0 comprising the core and iron oxides in the shell, the generated iron sulfides (FeSx) were distributed over the iron oxides shell. The water contact angle results suggested S-nZVI was more hydrophobic than nZVI, which could prevent the oxidation of the inner Fe0 core with aqueous solution, furthermore, the electrochemical experiments demonstrated the FeSx improved the electron transfer efficiency from Fe0 core to contaminants, enhancing the reactivity of S-nZVI. Mechanism analysis confirmed that the electrostatic attraction, chemical precipitation, surface complexation and reduction occurred during the adsorption. S-nZVI with S/Fe molar ratio of 0.3 offered the best Pb(II) adsorption capacity, and higher pH value was favourable, the presence of co-existing cations (K+, Na+, Ca2+, Mg2+) all interfered the Pb(II) removal, followed as Ca2+ >Mg2+ > K+ > Na+. The pseudo-second-order kinetics and Langmuir model could well described the adsorption process, indicating that monolayer adsorption dominated the process. Thermodynamic results showed the adsorption was a spontaneous endothermic process, even after 4 cycles of recycling, the removal rate remained at 76.4 %, demonstrating S-nZVI had good reusability.

Electrocatalytic degradation of naphthenic acids using reduced graphene oxide modified nickel foam cathode: Role of surface structure and superoxide radical

In this work, the reduced graphene oxide (RGO) modified nickel foam (Ni-foam) was prepared via the hydrothermal reduction self-assembly method and was applied as the cathode for the effective electrocatalytic (EC) degradation of recalcitrant naphthenic acids (NAs) that are abundantly present in the petroleum industrial wastewater. The Ni@RGO cathode has greatly enhanced the production of H2O2 in the system to boost the degradation of 1-adamantanecarboxylic acid (ACA) that was a model NA compound. Results showed that the EC/Fe(III)/Ni@RGO system achieved complete ACA degradation within 15 min due to its elevated H2O2 generation and Fe(III)/Fe(II) circulation, compared to EC/Fe(III)/Ni-foam and EC/Fe(III)/Graphite systems. Interestingly, abundant ·O2– radicals, which were produced in EC/Fe(III)/Ni@RGO system as a key intermediate for 2e- oxygen reduction reaction (ORR), could effectively accelerate the circulation of Fe(III)/Fe(II) to activate H2O2 to generate ·OH for ACA degradation. Results of material characterization, electrochemical analysis and density functional theory (DFT) calculations showed that Ni@RGO cathode has obtained elevated electron transfer efficiency compared to that of Ni-foam cathode. Surface structure of RGO, such as carbon edge and vacancy with specific configuration, residual –COOH oxygenation groups on RGO surface are main catalytic sites to enhance the capacity of 2e- ORR and electron capture processes in the system. This study provides new insights regarding the synthesis process of catalytic electrodes, the influence of carbon-based material structure on catalytic activity, and the critical role of free radicals in the electro-Fenton system with Ni@RGO cathode

In Situ Self-Inflating-Modeled Giant-Vesicle-Like Quantum Dot Assembly for Biomimetic Artificial Photosynthesis.

The study of biomimetic self-assembly is crucial for scientists aiming to understand the origin of life and construct biomimetic functional structures. In our endeavor to create a biomimetic photosynthetic assembly, we discover a self-inflation behavior that drives the components, MPA-CdSe quantum dots (QDs) and a solid cationic polyelectrolyte, CPPA, to form a giant-vesicle-like (GVL) architecture, termed GVL-QDs@CPPA. The in situ generation of osmotic pressure during the self-assembly of QDs onto swollen CPPA in water was found to cause this self-inflation process. The resulting vesicle-like structure exhibits spatial characteristics similar to those of natural photosynthetic cells, with QDs acting as pigments uniformly distributed on the CPPA membranes, which have embedded cobalt catalytic centers. This architecture ensures optimal absorption of visible light and facilitates efficient electron transfer between the QDs and catalytic centers. As a result, GVL-QDs@CPPA assemblies efficiently harness photogenerated electrons and holes to convert protons and isopropanol into hydrogen (H2) and acetone, respectively, achieving a nearly 1:1 ratio of the reduction product (H2) to the oxidation product (acetone).

Recent Research Advancements in Carbon Fiber‐Based Anode Materials for Lithium‐Ion Batteries

Energy consumption is a critical element in human evolution, and rapid advances in science and technology necessitate adequate energy. As human society evades, the advancement of energy storage components has become critical in addressing societal challenges. Lithium‐ion batteries (LIBs) are promising candidates for future extensive use as optimal energy storage devices. However, the current limitations of LIBs pose a challenge to their continued dominance. Researchers are constantly exploring new materials to enhance the performance of LIBs, and carbon fiber (CF) is a dominant contender in this pursuit. The high electrical conductivity of carbon‐based materials benefits the battery system by facilitating efficient electron transfer and improving overall performance. CF‐based materials provide enhanced energy storage capacity and cycling stability in LIBs. Progress in carbon‐based materials has resulted in electrodes with increased surface areas, enabling greater rates of charging and discharging. In addition, the exceptional corrosion resistance of CF ensures the durability and robustness of LIBs. A comprehensive review is carried out on the correlation between the material's structure and its electrochemical performance, with a special emphasis on the uses of pure carbon fibers, transition metal oxides, sulfides, and MXene carbon‐based transition metal compounds in LIBs.

Unraveling the molecular determinants of a rare human mitochondrial disorder caused by the P144L mutation of FDX2.

Episodic mitochondrial myopathy with or without optic atrophy and reversible leukoencephalopathy (MEOAL) is a rare, orphan autosomal recessive disorder caused by mutations in ferredoxin-2 (FDX2), which is a [2Fe-2S] cluster-binding protein participating in the formation of iron-sulfur clusters in mitochondria. In this biosynthetic pathway, FDX2 works as electron donor to promote the assembly of both [2Fe-2S] and [4Fe-4S] clusters. A recently identified missense mutation of MEOAL is the homozygous mutation c.431C>T (p.P144L) described in six patients from two unrelated families. This mutation alters a highly conserved proline residue located in a loop of FDX2 that is distant from the [2Fe-2S] cluster. How this Pro to Leu substitution damages iron-sulfur cluster biosynthesis is unknown. In this work, we have first compared the structural, dynamic, cluster binding and redox properties of WT and P144L [2Fe-2S] FDX2 to have clues on how the pathogenic P144L mutation can perturb the FDX2 function. Then, we have investigated the interaction of both WT and P144L [2Fe-2S] FDX2 with its physiological electron donor, ferredoxin reductase FDXR, comparing their electron transfer efficiency and protein-protein recognition patterns. Overall, the data indicate that the pathogenic P144L mutation negatively affects the FDXR-dependent electron transfer pathway from NADPH to FDX2, thereby reducing the capacity of FDX2 in assembling both [2Fe-2S] and [4Fe-4S] clusters. Our study also provided solid molecular evidences on the functional role of the C-terminal tail of FDX2 in the electron transfer between FDX2 and FDXR.

Photocatalytic H2O2 production over boron-doped g-C3N4 containing coordinatively unsaturated FeOOH sites and CoOx clusters

Graphitic carbon nitride (g-C3N4) has gained increasing attention in artificial photosynthesis of H2O2, yet its performance is hindered by sluggish oxygen reduction reaction (ORR) kinetics and short excited-state electron lifetimes. Here we show a B-doped g-C3N4 (BCN) tailored with coordinatively unsaturated FeOOH and CoOx clusters for H2O2 photosynthesis from water and oxygen without sacrificial agents. The optimal material delivers a 30-fold activity enhancement compared with g-C3N4 under visible light, with a solar-to-chemical conversion efficiency of 0.75%, ranking among the forefront of reported g-C3N4-based photocatalysts. Additionally, an electron transfer efficiency reaches 34.1% for the oxygen reduction reaction as revealed by in situ microsecond transient absorption spectroscopy. Experimental and theoretical results reveal that CoOx initiates hole–water oxidation and prolongs the electron lifetime, whereas FeOOH accepts electrons and promotes oxygen activation. Intriguingly, the key to the direct one-step two-electron reaction pathway for H2O2 production lies in coordinatively unsaturated FeOOH to adjust the Pauling-type adsorption configuration of O2 to stabilize peroxide species and restrain the formation of superoxide radicals.

Green Synthesis and Enhanced Photocatalytic Performance of rGO/ZnO/Fe3O4 Nanocomposites: A Sustainable Approach to Environmental Remediation.

The fast industrialization and mounting pollution have necessitated the need for advanced materials in order to degrade pollutants efficiently. Metal oxide-based and graphene-derivative photocatalytic nanocomposites are excellent for harnessing light energy in environmental remediation. Among them, ZnO-based nanocomposites have drawn considerable attention because of their high photocatalytic activity and stability. However, improving the performance of these nanocomposites is still necessary for their wide applications. This study explores the green synthesis, detailed characterization, and enhanced photocatalytic efficiency of reduced graphene oxide rGO/ZnO/Fe3O4 nanocomposites. The nanocomposites were synthesized via a hydrothermal method, utilizing milk thistle extract as a natural reducing agent, representing a novel and sustainable approach to fabricating magnetic rGO/Fe3O4 nanocomposites. These composites were further integrated with zinc oxide to produce a multifunctional material, exhibiting high surface area, superior electrical and thermal conductivity, and robust mechanical strength. The photocatalytic performance was significantly enhanced due to the synergistic interaction between graphene and metal oxide nanoparticles, leading to efficient degradation of environmental pollutants. Electrochemical analysis via cyclic voltammetry revealed distinctive redox peaks, demonstrating efficient electron transfer processes essential for applications in energy conversion and storage. This green synthesis not only provides a sustainable pathway for the development of advanced nanocomposites but also underscores their potential in a wide range of applications, including environmental remediation, sensing, energy storage, and optoelectronics.

Fabrication of heterostructure multilayer devices through the optimization of Bi-metal sulfides for high-performance quantum dot-sensitized solar cells.

In this work, a titanium dioxide and lead sulfide (TiO2/PbS) nano-size heterostructure with tin sulfide was fabricated and coated via a two-step direct deposition process. Its microstructure, morphology, elemental composition, optical absorption, and photochemical activity were investigated. Linear sweep voltammetry and cyclic voltammetry curves substantiated its catalytic activity, indicating quantum dot effects of a well-developed space charge domain on the surface of the hybrid structure. These give rise to electron-hole recombination suppression and a high charge mobility rate. Moreover, direct stabilization was identified in current density, corresponding to the hybrid structures limiting the diffusion current process. Higher J SC values observed were substantiated by the role of quantum dot-size effects and enhanced crystalline structures, leading to a reduction in series resistance and an improved conversion efficiency of 10.05%. Overall, theoretical analyses and empirical findings indicated that the seamless migration of photoexcited electrons across the interfaces of SnS and PbS is linked to quantum dot effect synergy. This is facilitated by the space charge region, which serves as a conduit for efficient electron transfer between the respective materials.

High Performance H2S Sensor Based on Ordered Fe2O3/Ti3C2 Nanostructure at Room Temperature.

The utilization of a heterogeneous nanojunction design has shown significant enhancements in the gas sensing capabilities of traditional metal oxide gas sensors. In this study, a novel room temperature H2S gas sensor employing Fe2O3 functionalized Ti3C2 MXene as the sensing material has been developed. This sensor exhibits a broad detection range (0.01-500 ppm), low detection limit (10 ppb), and rapid response/recovery times (10 s/15 s), making it ideal for ppb-level H2S detection. The exceptional gas sensitivity of Fe2O3/Ti3C2 composite to H2S can be attributed to several key factors. First, the unique layered frame structure of Fe2O3/Ti3C2 significantly amplifies the surface area of the hybrid material, enhancing the absorption and diffusion capabilities of H2S molecules. Second, the abundance of functional groups (-O, -OH, and -F) on the surface of Ti3C2 MXene nanosheets provides additional active sites for H2S adsorption, The density functional theory calculation confirms that the adsorption energy of the Fe2O3/Ti3C2 composite for H2S (-2.93 eV) is significantly lower than that of pure Fe2O3 (-2.37 eV) and Ti3C2 (-0.2 eV). Lastly, the remarkable metal conductivity of Ti3C2 MXene ensures efficient electron transfer, thereby enhancing overall sensing performance.

Nanostructured defects-rich black-ZnO/biowaste-derived carbon composites for efficient visible light-driven hydrogen generation: A study on the role of C–Zn@C–O–Zn interface

The use of a highly efficient and noble-metal-free cocatalyst, which is being pursued to create hydrogen (H2) via photocatalysis, has been the subject of many studies. In this work, a unique ultrasonication-assisted laser beam irradiation process is employed to synthesize a new carbon material generated from pineapple peel biowaste (ppC) and mix it with oxygen-deficient black zinc oxide (b-ZnOvac) nanoparticles. In the ppCx@b-ZnOvac nanostructures, the XPS analysis verified the presence of surface oxygen (O2) defects and vacancies as well as chemical interactions between carbon and zinc via carbon-zinc (C–Zn) and carbon-oxygen-zinc (C–O–Zn) connection interfaces. Following optimization, the visible light active photocatalytic H2 production rate of the ppC10@b-ZnOvac nanostructures reached 215.92 μmol h−1 g−1, which was the highest. The positive synergistic interaction between b-ZnOvac and ppC is responsible for the significant increase in the rate of H2 generation. Furthermore, the significant chemical bond between ppC and b-ZnOvac via the C–Zn/C–O–Zn interface, as well as the development of surface O2 vacancy defects in b-ZnOvac, improve the efficient transfer of energetic electrons and make visible active photocatalytic H2 production from methanol in the ppCx@b-ZnOvac nanostructures easier. Our work presents a new strategy for chemically generating affordable carbon materials through the use of metal oxide-based photocatalysts with surface O2 vacancy defects and bio-waste. Applications such as water splitting, energy production, and environmental remediation show promise for these advanced materials for large-scale field applications.