Abstract

Cu₂O-n thin films were successfully electrodeposited from a Cu(II) lactate solution containing different concentrations of copper(II) sulfate (CuSO₄) and 1 M lactic acid (C₃H₆O₃) at pH 6.5. The electrochemical behaviour of Cu₂O thin films has been investigated by means of cyclic voltammetry (CV), chronoamperometry (CA). The nucleation behaviour of the deposited Cu₂O has been studied on FTO substrates as a function of Cu²⁺ concentration. It was found that the nucleation changes from progressive to instantaneous with increasing Cu²⁺ concentration. Many electrochemical parameters were investigated such as transfer coefficient, diffusion coefficient, cathodic and anodic charges, nucleation rate etc. The effect of the nucleation mechanism on microstructural and optical properties of Cu₂O were investigated by X-ray diffractometry (XRD) and ultraviolet visible spectrophotometry (UV–Vis–NIR) and photoluminescence (PL). The optimal concentration of Cu²⁺ ions was found to be 0.075 and 0.1 M obtained with instantaneous nucleation process. The high photoluminescence (PL) efficiency observed indicating good optical properties with a high carrier density, small depletion layer, high photo-generated electron–hole pairs, narrow band gap and low charge transfer resistance. This results exhibit a high photoelectric performance.

中文翻译：

---

硫酸铜浓度对n型Cu 2 O薄膜电化学成核过程，生长和性能的影响

摘要

的Cu ₂ O-正薄膜已成功地从铜电解（II）含有不同浓度的铜的乳酸盐溶液（II），硫酸（硫酸铜₄）和1M乳酸（C ₃ H ^ ₆ ö ₃）在pH6.5。已经通过循环伏安法（CV），计时电流法（CA）研究了Cu ₂ O薄膜的电化学行为。已经研究了在FTO基板上沉积的Cu ₂ O的成核行为随Cu ²⁺浓度的变化。研究发现，随着Cu ^2+的增加，形核从渐进性转变为瞬时性。浓度。研究了许多电化学参数，如转移系数，扩散系数，阴极和阳极电荷，成核速率等。通过X射线衍射（XRD）和紫外可见光研究了成核机理对Cu ₂ O的微观结构和光学性质的影响。分光光度法（UV–Vis–NIR）和光致发光（PL）。发现通过瞬时成核过程获得的最佳Cu ²⁺离子浓度为0.075和0.1M。观察到的高光致发光（PL）效率表明它具有良好的光学性能，具有高的载流子密度，小的耗尽层，高的光生电子-空穴对，窄的带隙和低的电荷转移电阻。该结果显示出高的光电性能。