Synthesis and Characterization of High-Photoactivity Electrodeposited Cu2O Solar Absorber by Photoelectrochemistry and Ultrafast Spectroscopy
Synthesis and Characterization of High-Photoactivity Electrodeposited Cu2O Solar Absorber by Photoelectrochemistry and Ultrafast Spectroscopy
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DOI：
10.1021/jp301176y
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发表时间：
2012-04-05
影响因子：
3.7
通讯作者：
Graetzel, Michael
中科院分区：
文献类型：
--
作者：
Paracchino, Adriana;Brauer, Jan Cornelius;Graetzel, Michael
本文系统研究了电沉积参数对Cu_2O光电化学性质的影响。沉积变量（温度，pH值和沉积电流密度）对电导率的影响已被广泛探讨，在过去的半导体，但在AM 1.5照明下的水溶液中的光电化学响应的电沉积过程的优化已收到少得多的关注。在这项工作中，我们分析了在不同条件下沉积的CuO薄膜的光活性，并将光响应与形貌，薄膜取向和电学性质相关联。采用线性扫描伏安法在模拟调幅1.5的短脉冲光照下测定了其光电化学响应.对于1.3 μ m的膜厚度，在0.25 V（相对于RHE）下获得的最高光电流为-2.4 mA cm（-2）。这是迄今为止在AM 1.5照明下该材料在水性电解质中达到的最高报道值。利用紫外-可见光谱和电化学阻抗谱研究了最具光活性电极的光电性质，利用光泵太赫兹探测光谱测量了少子寿命和扩散长度。
We present a systematic study on the effects of electrodeposition parameters on the photoelectrochemical properties of Cu2O. The influence of deposition variables (temperature, pH, and deposition current density) on conductivity has been widely explored in the past for this semiconductor, but the optimization of the electrodeposition process for the photoelectrochemical response in aqueous solutions under AM 1.5 illumination has received far less attention. In this work, we analyze the photoactivity of Cu2O films deposited at different conditions and correlate the photoresponse to morphology, film orientation, and electrical properties. The photoelectrochemical response was measured by Linear sweep voltammetry under chopped simulated AM 1.5 illumination. The highest photocurrent obtained was -2.4 mA cm(-2) at 0.25 V vs RHE for a film thickness of 1.3 mu m. This is the highest reported value reached so far for this material in an aqueous electrolyte under AM 1.5 illumination. The optical and electrical properties of the most photoactive electrode were investigated by UV-vis spectroscopy and electrochemical impedance, while the minority carrier lifetime and diffusion length were measured by optical-pump THz-probe spectroscopy.