Dataset for "Electrodeposited p-Cu2O Films – Role of Redox-Active Compounds Under Photoelectrochemical Operation Revisited"

The p-type semiconducting copper oxides CuO and Cu2O are of interest for the conversion of solar energy due to their medium wide bandgap. The position of their conduction band should allow for reductive processes in junctions with electrolytes under irradiation. In this work, on Cu2O, the efficiency of several such processes in competition with self-reduction was studied.Thin films of Cu2O were synthesised via potentiostatic electrodeposition on FTO (fluorine doped SnO2 on glass) using aqueous electrolytes. Deposition parameters (electrolyte composition, electrode potential, temperature) had a great influence on electrode properties (phase purity, preferential orientation). Electrodeposited Cu2O films were p-type. In junctions with aqueous electrolytes, under electrical bias, cathodic and photocathodic currents passed which increased dramatically when reducible redox compounds were added. The influence of various redox couples (O2, H2O2, methylviologen) and their concentration in the electrolyte on the stability of the electrodes was studied.Long time experiments showed that oxygen saturated and H2O2 containing electrolytes gave rise to constant photocurrents and no alteration of the electrodes was found by XRD. With the investigated redox couples, no product of interest was produced.p型半导体氧化铜（CuO和Cu2O）因具有中等宽带隙，在太阳能转换领域受到广泛关注。其导带能级位置使得该材料在与电解质形成的结区中，可在光照下发生还原反应。本研究以Cu2O为对象，探究了多种与自还原过程竞争的上述还原反应的反应效率。 本研究采用水性电解质，通过恒电位电沉积法在FTO（fluorine doped SnO2 on glass，氟掺杂氧化锡玻璃）基底上制备Cu2O薄膜。沉积参数（电解质组成、电极电位、反应温度）对电极性能（相纯度、择优取向）具有显著影响。经电沉积制备的Cu2O薄膜均为p型半导体。 在与水性电解质形成的结区中施加偏压时，可观测到阴极电流与光阴极电流；当体系中加入可还原的氧化还原化合物后，这两类电流会显著提升。本研究探究了多种氧化还原对（O2、H2O2、甲基紫精（methylviologen））及其在电解质中的浓度对电极稳定性的影响。 长期实验结果表明，采用氧气饱和及含H2O2的电解质时，可获得稳定的光电流，且通过XRD（X射线衍射）表征未发现电极发生结构变化。针对本次研究所涉及的氧化还原对，未检测到目标产物生成。