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Construction of a homojunction is an effective strategy for effective charge transfer to suppress charge carrier recombination in augmented photocatalysis. The present work reveals the synthesis of homojunction formation through the reinforcement of Cd nanostructures into a solid lattice of zinc vanadate (Zn 3 V 2 O 8 , ZnV) using the hydrothermal method. The formation of a homojunction between cadmium vanadate (CdV, Cd 3 V 2 O 8 ) and ZnV was confirmed by various spectroscopic and electron microscopic techniques such as Fourier-transform infrared (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) associated with energy-dispersive X-ray (EDX) mapping, transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and ultraviolet-visible spectrophotometry (UV-Vis). The synthesized material was explored for photocatalytic hydrogen (PC H 2 ) production using the water splitting process under visible-light illumination. The spectroscopic and experimental results revealed that the formation of a CdV/ZnV homojunction significantly improved the transport of photogenerated charge carriers (electron-hole pairs) and thus resulted in enhanced H 2 production efficiency (366.34 μmol g -1 h -1 ) as compared to pristine ZnV (229.09 μmol g -1 h -1 ) and CdV (274.91 μmol g -1 h -1 ) using methanol as a sacrificial reagent (SR) with water under visible-light illumination. The synergistic effect of Cd on ZnV NPs resulted in band gap reduction and broadened visible light absorption which was attributed to enhanced H 2 production. The current study explains how a homojunction affects various features of important factors behind photocatalytic activity, which supports significant insights into the advancement of materials in the future.

Designing efficient electrocatalytic systems through facile synthesis remains a formidable task. To address this issue, this paper presents the design of a combination material comprising two transition metal oxides (copper oxide and manganese oxide (CuO/MnO 2 )), synthesized using a conventional microwave technique to efficiently engage as an active oxygen evolution reaction (OER) catalyst. The structural and morphological properties of the composite were confirmed by the aid of X-ray diffraction (XRD) studies, field emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), and energy-dispersive spectrometry (EDS). FESEM clearly indicated well-aligned interlacing of CuO with MnO 2 . The OER performance was carried out in 1 M KOH. The assembled CuO/MnO 2 delivered a benchmark current density (j = 10 mA cm -2 ) at a minimal overpotential (η = 294 mV), while pristine CuO required a high η (316 mV). Additionally, the CuO/MnO 2 electrocatalyst exhibited stability for more than 15 h. These enhanced electrochemical performances were attributed to the large volume and expanded diameter of the pores, which offer ample surface area for catalytic reactions to boost OER. Furthermore, the rate kinetics of the OER are favored in composite due to low Tafel slope (77 mV/dec) compared to CuO (80 mV/dec).