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A heterostructure photocatalyst composed of CuWO4-modified SnO2 (CuWO4/SnO2) was synthesized using a simple wet -chemical methods and evaluated for its ability to degrade Rose Bengal (RB) dye under visible light irradiation. Comprehensive characterization of the samples was conducted using Ultraviolet -visible diffuse reflectance spectroscopy (UV-vis -DRS), X-ray diffraction (XRD), scanning electron microscopy (SEM) with energy - dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), high -resolution TEM (HR -TEM), Brunauer-Emmett -Teller surface analysis (BET), and X-ray photoelectron spectroscopy (XPS). The results demonstrated that CuWO4/SnO2 exhibited significantly superior photocatalytic activity compared to CuWO4 or SnO2 alone. This enhanced efficiency is attributed to the effective charge transfer between SnO2 and CuWO4 nanoparticles, which considerably reduces electron -hole recombination energy levels. Optimal conditions for maximum RB degradation under visible light were found to be a pH of 8, a dye concentration of 20 µM, and a photocatalyst dosage of 0.2 g/L, achieving a high degradation efficiency of 98.5% within 180 minutes. The outstanding photocatalytic performance of CuWO4/SnO2 is primarily due to the profecient separation of light induced electron -hole pairs. The reactive species involved in the photocatalytic degradation of RB include holes (h+) and superoxide radicals (O2• - ). This study highlights the potential of CuWO4/SnO2 as an effective photocatalyst for environmental remediation applications. [ABSTRACT FROM AUTHOR]

A rhodium‐catalyzed [5+1] cycloaddition via C−H activation/O‐annulation strategy for synthesizing biologically interesting isochromenes is presented. This protocol selectively provides divergently functionalized isochromenes containing spirosuccinimide and maleimide scaffolds according to the maleimides and itaconimides used as the substrates. This methodology exhibits an extensive substrate scope, remarkable functional group tolerance, and high regioselectivity. [ABSTRACT FROM AUTHOR]

In this study, n‐type SnO2 was synthesized and modified with p‐type NiWO4 to create a new NiWO4/SnO2 p–n heterojunction photocatalyst for effective organic dye degradation (Amaranth). X‐ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV–Vis diffuse reflection spectroscopy (DRS), and Brunauer–Emmett–Teller (BET) surface area analysis were all used to evaluate the synthesized materials. Through its internal electric field and strong driving force, the composite photocatalyst with p–n heterojunction considerably enhances charge generation and suppresses photogenerated electron–hole recombination, which would be beneficial to boost their photocatalytic performance. At 180 min, the NiWO4/SnO2 photocatalyst had the maximum efficiency for degrading Amaranth, up to 93%. Finally, the experimental results were used to rationally analyze the photodegradation mechanism. [ABSTRACT FROM AUTHOR]

Intrinsic characteristics of organic semiconductor‐based hole transport materials (HTMs) such as facile synthesizability, energy level tunability, and charge transport capability have been highlighted as crucial factors determining the performances of perovskite photovoltaic (PV) cells. However, their properties in the excited state have not been actively studied, although PVs are operated under solar illumination. Here, the characteristics of organic HTMs in their excited state such as transition dipole moment can be a decisive factor that can improve built‐in potential of PVs, consequently enhancing their charge extraction property as well as reducing carrier recombination. Moreover, the aggregation property of organic semiconductors, which has been an essential factor for high‐performance organic HTMs to improve their carrier transport property, can induce a synergistic effect with their excited state property for the high‐efficiency perovskite PVs. Additionally, it is also confirmed that their optical bandgaps, manipulated to have their absorption in the UV region, are beneficial to block UV light that degrades the quality of perovskite, consequently improving the stability of perovskite PV in p–i–n configuration. As a proof‐of‐concept, a model system, composed of triarylamine and imidazole‐based organic HTMs, is designed, and it is believed that this strategy paves a way toward high‐performance and stable perovskite PV devices. [ABSTRACT FROM AUTHOR]

A p-type CuO/n-type Pb 2 O 3 heterojunction photocatalyst was prepared by a simple wet chemical process and the photocatalytic ability was evaluated for the degradation of Rose Bengal (RB) under visible light irradiation. Synthesized nanocatalysts were characterized by X-ray diffraction (XRD), UV–vis diffuse reflectance spectroscopy (DRS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Energy-dispersive X-ray spectroscopy (EDS), Brunauer-Emmett-Teller (BET) surface area analysis, and X-ray photoelectron spectroscopy (XPS). The p-n heterojunction of CuO-Pb 2 O 3 nanostructures can promote the light absorption capability of photocatalyst and charge separation of electron-hole pairs. Photodegradation assays showed that the addition of CuO effectively enhanced the photocatalytic activity of CuO-Pb 2 O 3 under visible light irradiation ( λ max > 420 nm). Compared with pure Pb 2 O 3 and CuO, the CuO-Pb 2 O 3 exhibited significantly enhanced photocatalytic degradation activity. The reaction rate constant of CuO-Pb 2 O 3 is 0.092 min −1 , which is much higher than those of CuO (0.073 min −1 ) and Pb 2 O 3 (0.045 min −1 ). [ABSTRACT FROM AUTHOR]

Methoxy‐functionalized triphenylamine‐imidazole derivatives that can simultaneously work as hole transport materials (HTMs) and interface‐modifiers are designed for high‐performance and stable perovskite solar cells (PSCs). Satisfying the fundamental electrical and optical properties as HTMs of p‐i‐n planar PSCs, their energy levels can be further tuned by the number of methoxy units for better alignment with those of perovskite, leading to efficient hole extraction. Moreover, when they are introduced between perovskite photoabsorber and low‐temperature solution‐processed NiOx interlayer, widely featured as an inorganic HTM but known to be vulnerable to interfacial defect generation and poor contact formation with perovskite, nitrogen and oxygen atoms in those organic molecules are found to work as Lewis bases that can passivate undercoordinated ion‐induced defects in the perovskite and NiOx layers inducing carrier recombination, and the improved interfaces are also beneficial to enhance the crystallinity of perovskite. The formation of Lewis adducts is directly observed by IR, Raman, and X‐ray photoelectron spectroscopy, and improved charge extraction and reduced recombination kinetics are confirmed by time‐resolved photoluminescence and transient photovoltage experiments. Moreover, UV‐blocking ability of the organic HTMs, the ameliorated interfacial property, and the improved crystallinity of perovskite significantly enhance the stability of PSCs under constant UV illumination in air without encapsulation. Methoxy‐functionalized triphenylamine‐imidazole derivatives, simultaneously working as hole transport materials and bifacial interface‐modifiers passivating defects in the perovskite and NiOx layers, are developed for high‐performance and stable perovskite solar cell. They are advantageous to improve charge‐extraction kinetics of devices and significantly enhance the stability of devices under constant UV illumination in air. [ABSTRACT FROM AUTHOR]

In this work, new strategies were developed to prepare 1D-V 2 MoO 8 (VMO) rods from 2D V-doped MoSe 2 nanosheets (VMoSe 2 ) with good control over morphology and crystallinity by a facile hydrothermal and calcination process. The morphological changes from 2D to 1D rods were controlled by changing the calcination temperature from 300 to 600 °C. The elimination of Se and the incorporation of O into the V-Mo structure were evaluated by TGA, p-XRD, Raman, FE-SEM, EDAX, FE-TEM, and XPS analyses. These results prove that the optimization of the physical parameters leads to changes in the crystal phase and textural properties of the prepared material. The VMoSe 2 and its calcined products were investigated as electrochemical sensors for the detection of the antibacterial drug nitrofurantoin (NFT). At a calcination temperature of 500 °C, the modified screen-printed carbon electrodes (SPCE) proved to be an excellent electrochemical sensor for the detection of NFT in neutral media. Under the optimized conditions, VMO-500 °C/SPCE exhibits low detection limit (LOD) (0.015 μM), wide linear ranges (0.1-31, 47-1802 μM), good sensitivity, and selectivity. The proposed sensor was successfully used for the analysis of NFT in real samples with good recovery results. Moreover, the reduction potential of NFT agreed well with the theoretical analysis using quantum chemical calculations, with the B3LYP with 6-31G(d,p) basis set predicting an E 0 value of -0.45 V. The interaction between the electrode surface and NFT via the LUMO diagram and the electrostatic potential surface is also discussed.

Methoxy-functionalized triphenylamine-imidazole derivatives that can simultaneously work as hole transport materials (HTMs) and interface-modifiers are designed for high-performance and stable perovskite solar cells (PSCs). Satisfying the fundamental electrical and optical properties as HTMs of p-i-n planar PSCs, their energy levels can be further tuned by the number of methoxy units for better alignment with those of perovskite, leading to efficient hole extraction. Moreover, when they are introduced between perovskite photoabsorber and low-temperature solution-processed NiO x interlayer, widely featured as an inorganic HTM but known to be vulnerable to interfacial defect generation and poor contact formation with perovskite, nitrogen and oxygen atoms in those organic molecules are found to work as Lewis bases that can passivate undercoordinated ion-induced defects in the perovskite and NiO x layers inducing carrier recombination, and the improved interfaces are also beneficial to enhance the crystallinity of perovskite. The formation of Lewis adducts is directly observed by IR, Raman, and X-ray photoelectron spectroscopy, and improved charge extraction and reduced recombination kinetics are confirmed by time-resolved photoluminescence and transient photovoltage experiments. Moreover, UV-blocking ability of the organic HTMs, the ameliorated interfacial property, and the improved crystallinity of perovskite significantly enhance the stability of PSCs under constant UV illumination in air without encapsulation., Competing Interests: The authors declare no conflict of interest.