Efficiency enhancement in photoelectrochemical water splitting: Defect passivation and boosted charge transfer kinetics of zinc oxide nanostructures via chalcopyrite/chalcogenide mix sensitization

Impact on the Photocatalytic Dye Degradation of Morphology and Annealing-Induced Defects in Zinc Oxide Nanostructures

“…The widening DLE signals of ZnO morphologies are due to the grain growth with increasing annealing temperature. As reported in earlier studies, annealing temperatures and morphology significantly influence the type and concentration of defects in the ZnO nanostructures 25,65 At high-temperature annealing (800 °C), all morphologies show the existence of neutral oxygen vacancies (V O ) located at ∼650 nm.…”

“…As reported in earlier studies, annealing temperatures and morphology significantly influence the type and concentration of defects in the ZnO nanostructures. 25 , 64 , 65 At high-temperature annealing (800 °C), all morphologies show the existence of neutral oxygen vacancies (V O ) located at ∼650 nm. It is also observed that the DLE based on doubly charged oxygen vacancies (V O ++ ) emission reaches the highest point as the temperature increases.…”

“…Another issue that has come to the fore, especially in recent years, is that ZnO materials’ optical, electrical, and catalytic performances vary according to their defect structures. − It has been known that excess zinc and oxygen vacancies form donor states at 0.05 eV below the conduction band. , Oxygen vacancies (O v ), Zn interstitials (Zn i ), and hydrogen background impurities have been suggested as candidates for native donors in ZnO . There has been a great discussion about the production conditions of native donors in ZnO and their electrical and optical properties. − Halliburton et al have reported that annealing ZnO crystals at 1100 °C in zinc vapor increased n-type electrical conductivity .…”

Solar-assisted all-solid supercapacitors using composite nanostructures of ZnO nanowires with GO and rGO

“…36-1451). 2,48 However, there is no characteristic diffraction peak of either GO or rGO, consistent with the previous reports on rGO/ZnO and GO/ZnO composites. 38,42 The absence of the characteristic GO or rGO diffraction peaks is attributed to the disorderly stacked rGO/GO planes in the composites with ZnO NW or due to the low concentration of GO or rGO in the composites.…”

“…In particular, the use of solar energy as a renewable energy source has become a growing concern to diminish the dependence on fossil fuels. [1][2][3][4][5] Nowadays, several technologies for energy conversion and storage such as photovoltaic (PV) solar cells, 6 photoelectrochemical (PEC) cells, [7][8][9][10] Li-ion batteries, 11 PEC redox-flow batteries, 12 and supercapacitors (SC) 13 have been developed to meet the energy demand. In particular, in the last few years, supercapacitors have attracted significant attention due to their low-cost, safe operation, fast charge-discharge cycles, high power density, and cyclic stability.…”