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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]

This study reports on the modification of surface plasmon resonance (SPR) chips with molybdenum disulfide–molybdenum trioxide (MoS2–MoO3) microflowers to detect the tuberculosis (TB) markers of CFP-10. The MoS2–MoO3 microflowers were prepared by hydrothermal methods with variations in the pH and amount of trisodium citrate (Na3Ct), which were projected to influence the shape and size of microflower particles. The analysis shows that optimum MoS2–MoO3 hybrid microflowers were obtained at neutral pH using 0.5 g Na3Ct. The modified SPR biosensor exhibits a ten times higher response than the bare Au. Moreover, increasing MoS2–MoO3 thickness results in a higher detection response, sensitivity, and a smaller limit of detection (LOD). Using the optimized material composition, the Au/MoS2–MoO3-integrated SPR sensor can demonstrate sensitivity and LOD of 1.005 and 3.45 ng mL−1, respectively. This biosensor also has good selectivity, stability, and reproducibility based on cross-sensitivity characterization with other analytes and repeated measurements on several chips with different storing times and fabrication batch. Therefore, this proposed SPR biosensor possesses high potential to be further developed and applied as a detection technology for CFP-10 in monitoring and diagnosing TB. [ABSTRACT FROM AUTHOR]

A photoelectrochromic device (PECD) is a combination of a dye-sensitized solar cell (DSSC) and an electrochromic device (ECD) that directly generates transmittance contrast from solar radiation without an additional power source. In terms of application, PECDs have recently been utilized as self-powered smart windows for eco-friendly green buildings. The majority of PECDs have exceptional optical performance in the visible light region, with their electrochromic property regulating the indoor luminance. Nonetheless, indoor temperature regulation is also a potential opportunity that might be examined further for PECDs. As the temperature is highly correlated with the incident flux of infrared light, this study presents a near-infrared photoelectrochromic device (NIR-PECD) with WO3 as the electrochromic material for blocking infrared radiation, realizing indoor thermal management without external power. The NIR-PECD exhibited the ability of thermal modulation and lowered the indoor temperature with a transmittance contrast in the NIR region, demonstrating a transmittance contrast (ΔT) of 40.2% and an outstanding photocoloration efficiency (PhCE) of 55.85 cm2 min−1 W−1 at the wavelength of 1000 nm. In addition, the NIR-PECD also displayed a 5.6 °C temperature difference between the colored and bleached states, indicating the thermal management capabilities of keeping the interior cool in the colored state by blocking the NIR. As a further application, NIR-PECDs can be used as self-powered smart windows in green buildings to achieve internal temperature control without external power. [ABSTRACT FROM AUTHOR]