摘要 本研究，在氧化鋅奈米柱以電沉積成長於銦錫氧化物玻璃上，並在氧化鋅奈米柱上，製備的氧化鈷（II）奈米顆粒作為光電化學（PEC）系統中的光陽極，將水分解成氫和氧。 透過在氧化鋅奈米柱表面成長氧化鈷奈米粒子，光電化學器件中的半導體光陽極提高了太陽光吸收光譜和光電化學性能。 與未披覆氧化鈷之氧化鋅氧化鋅奈米柱光陽極的光化學水分解效率相比，太陽水分解效率提高了約2.6倍。 在這裡我們報告低成本和簡單的方法來定制PEC太陽能水分解池中的高性能光陽極，同時也報告了其可持續替代能源研究的發展和應用。

Cobalt (II) oxide nanoparticles fabricated on ZnO nanorods/ITO glass substrate act as photoanode in photoelectrochemical (PEC) system to split water into hydrogen and oxygen. CoO nanoparticals were formed on the surface of ZnO nanorods due to thermal decomposition of cobalt acetate tetrahydrate precursor under Argon gas at 300oC in 2 hours. The optimize condition is approximately 300 µl precursor per 1 cm2 of ZnO nanorods/ ITO substrate.
XRD and SEM were used to characterize the nanostructured CoO and ZnO. Pure phase CoO and hexagonal wurtzite structure ZnO were synthesized indicated by the XRD results. SEM analysis showed the morphology evolution of CoO upon addition of various concentration of cobalt acetate tetrahydrate precursor.
Uv-vis measurement indicated the extension of solar light spectrum absorption from ultraviolet region to 400-550 nm wavelengths of visible light region. The efficiency of photoelectron -chemical water splitting is enhanced approximately 2.6 times compared to the photochemical water splitting efficiency of bare ZnO nanorods/ITO glass photoanode calculated from current density vs potential (J-V curve measurement). SEM, TEM, EDS, XPS, PL measurement, cyclic voltammetry (CV curve) were also used to characterize the morphology, crystalline structure, chemical composition, recombination and electrochemical properties of CoO nanoparticles on the surface of ZnO nanorods.
Here we report low cost and simple method to tailor high performance photoanode in PEC solar water splitting cell but also its the development and application for sustainable alternative energy studies.

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