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The surface area of the working electrode plays a crucial role in determining the sensor's performance, especially in enzymatic sensors. Increasing the surface area of the working electrode has a significant impact on the sensor's functionality. This research focused on developing textile-based sensors using a multi-layer concept, employing the direct coating method. Two different sensors which are multilayer textile-based sensor (MTBS) and single-layer textile-based sensor (STBS) were prepared, while commercial screen-printed carbon electrode (SPCE) was also used as a comparison. The measurements were carried out using potassium ferricyanide solutions with concentrations of 0.01 M, 0.02 M, 0.03 M, 0.04 M, and 0.05 M at a voltage of 1 V, with a maximum duration up to the end of the measurement and a time interval of 0.5 s. According to the research findings, the fluid spreading speed of the SPCE is the lowest when compared to the spreading speeds of the MTBS and STBS. Specifically, the fluid spreading speed of the SPCE is 4.3 times slower than that of the STBS and 51 times slower than that of the MTBS. Utilizing a multi-layer concept with specific coatings can lead to better-performing sensors in terms of stability and sensitivity. The MTBS exhibits the greatest sensitivity, as indicated by its linear equation slope of 717.230 µA µM−1 cm−2. [ABSTRACT FROM AUTHOR]

The excessive energy demand of the conventional Haber–Bosch process for ammonia (NH3) generation, coupled with the disruptive effects of nitrate (NO3−) pollution on the global nitrogen cycle, has made the electrocatalytic nitrate reduction reaction (NO3−RR) an essential exit strategy for sustainable NH3 synthesis. However, the intricate multi-step proton and electron transfer process posed a great challenge in achieving high-efficiency electrocatalysts. In this study, we report a selective and highly active NO3−RR electrocatalyst featuring molecular M–Nx sites derived from the immobilization of Fe ions within N-doped graphene quantum dots (NGQDs). We demonstrated that the formation of molecular Fe–Nx coordination activated the NO3−RR of NGQDs-Fe, despite the initial inactivity of NGQDs. In situ Raman analysis revealed that those Fe–Nx sites served as favourable adsorption sites for *NO3. Such catalyst achieved an FE of 93% and a yield rate of 15.41 mmol h−1 cm−2 for NH3 at −0.8 V (vs. RHE) in an alkaline medium. These findings revealed the preferential sequential 2e− and 6e− transfer pathways over the direct 8e− pathway in the NO3−RR, which provides new mechanistic insights into the nitrate reduction reaction. [ABSTRACT FROM AUTHOR]

Copper zinc tin sulfide (CZTS) solar cells are one of the most promising possible substitutes for chalcopyrite copper indium gallium selenide (CIGS) in the future photovoltaic industry. This work reports on the preparation and characterization of a cobalt-doped zinc oxide (Zn1-xCoxOδ) thin-film buffer layer using the spin-coating technique on ITO back contact glass substrates. The effect of cobalt-doped zinc oxide on the structural, optical, morphological, and electrical properties of the obtained films has been investigated. The prepared thin-films were analyzed by several different characterization techniques such as X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), ultraviolet–visible (UV–Vis) spectroscopy and current density–voltage. (J-V) measurements. XRD analysis indicates all Zn1-xCoxOδ buffer layer films possess the wurtzite hexagonal polycrystalline structure with orientation (0 0 2). The images from FESEM analysis indicate the cross-sectional area and internal structure of Zn1-xCoxOδ buffer layer. The UV–Vis optical band gaps of the films were found to be in the range of 3.53–3.97 eV. The electrical analysis shows that the conductivity of cobalt-doped ZnO increases compared to the pure ZnO film without doping. The highest power conversion efficiency (PCE) of Zn0.91Co0.09Oδ is 0.54%. The analysis on cobalt-doped ZnO film showed that cobalt and zinc oxide are good candidates and potential for optoelectronic applications such as the production of solar cells which involved transparent electrodes. [ABSTRACT FROM AUTHOR]

Electrochemical biosensors have been widely used as advanced methods for virus detection. Ongoing efforts are being made to improve their performance by investigating novel materials as electrode modifiers. In this regard, two‐dimensional (2D) materials, such as graphene, transition metal dichalcogenides (TMDs), and transition metal carbides/nitrides (MXenes), have been extensively explored due to their exceptional structural and electrical properties for electrochemical biosensors. This review investigates and summarizes the recently developed 2D materials employed in virus detection. Various strategies to enhance the critical properties of 2D materials, including conductivity, surface area, active sites, selectivity, and wettability, on electrochemical biosensing platforms, which impact their performance, are discussed. Different types of 2D materials (pristine, derivatives, and composites) are described and subsequently evaluated regarding their applications in electrochemical biosensing. This review serves as a valuable guide for designing next‐generation, high‐performance electrochemical biosensors based on 2D materials. [ABSTRACT FROM AUTHOR]

TiO 2 remains one of the most popular materials used in catalysts, photovoltaics, coatings, and electronics due to its abundance, chemical stability, and excellent catalytic properties. The tailoring of the TiO 2 structure into two-dimensional nanosheets prompted the successful isolation of graphene and MXenes. In this review, facet-controlled TiO 2 and monolayer titanate are outlined, covering their synthesis route and formation mechanism. The reactive facet of TiO 2 is usually controlled by a capping agent. In contrast, the monolayer titanate is achieved by ion-exchange and delamination of layered titanates. Each route leads to 2D structures with unique physical and chemical properties, which expands its utilisation into several niche applications. We elaborate the detailed outlook for the future use and research studies of facet-controlled TiO 2 and monolayer titanates. Advantages and disadvantages of both structures are provided, along with suggested applications for each type of 2D TiO 2 nanosheets., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)