本論文研究為室溫下以液相合成法(Liquid phase synthesis)，改變不同前驅物比重、濃度、速率監測電位之變化，觀察並調整氧化亞銅(Cu2O)粉末尺寸，隨後搭配羥丙基纖維素(Hydroxypropyl cellulose, HPC)製備電極液，以浸塗(Dipping method)方式將電極液塗佈於銦錫氧化物(Indium Tin Oxide,ITO)玻璃基板製備光電陰極應用於水分解產氫研究探討製程溫度、烘烤時間及塗層數對其腐蝕特性、電化學特性之影響。結果顯示，經由X 光繞射及掃描式電子顯微鏡觀察，隨前驅物濃度增加，可獲得平均晶粒由18 nm至59 nm，掃描式電子顯微鏡分析所有樣品為球型結構之氧化亞銅粉體。經紫外光-可見光光譜分析，最大吸收峰位於675 nm 之可見光波段。由光電化學測試結果可知，Cu2O 光電極最佳製程參數為250 ℃持溫15 分鐘，而塗佈四次有較佳光電流(-0.065mA/cm2)，經由Mott-Schokkty 量測，塗佈四次之光電極有最小斜率(1.97×1017)代表其載子濃度較高。經由電化學阻抗頻譜 (Electrochemistry ImpedanceSpectroscopy, EIS)，塗佈四層之光電極可獲得最小阻抗之趨勢。由抗蝕性分析開路電位(Open circuit potential, OCP)、塔佛曲線(Tafel)可知，塗佈四次之光電極之試片具有最佳抗蝕性。;In this study, we attempted prepare Cu2O nanoparticles by liquid phase synthesis and fabricated them on Sn: In2O3 glass substrates as photocathode for photoelectrochemical (PEC) water splitting application via dipping method. Effect of percusor concentration on microstructural and optical proprties of Cu2O powder were investigated. On the ther hand, the dipping parameters (i.e., heating temperature, heating time and layers) of Cu2O photocathode also were discussed. Result from X-ray diffraction patterns, all sample were revealed the Cu2O phase. The Cu2O nanoparticles were affected by percusor concentration, the average particle size were increased from 18 to 59 nm with increasing percusor concentration. UV-vis. absorbance spectra shown all samples have an absorption peak at 675 nm wavelength in visible region. From fabrication of photocathode, the optimized dipping process conditions was 250 oC for 15min and four dipping times. Base up our observation, the four dipping times Cu2O photocathode had a better photocurrent (-0.065 mA/cm2) due to higher carrier concentration and lower resistance. Also, the four dipping times Cu2O photocathode revealed a better anti-corrosion property analyzed by open circuit potential (OCP) and Tafel plot.
