Zheng Kanghui, Zhou Yufeng, Wang Ruilin, Wang Gang, Xie Qiaomu, Wang Yonghua, Zheng Lin, Fu Ganhua, Pan Jingong, Peng Shou
College of Materials Science and Engineering, Sichuan University, Chengdu 610065, China.
CNBM (Chengdu) Optoelectronic Materials Co., Ltd., Chengdu 610207, China.
ACS Appl Mater Interfaces. 2025 Feb 12;17(6):9207-9218. doi: 10.1021/acsami.4c16540. Epub 2025 Jan 31.
Broadening the alloyed CdSeTe region in the absorber layer is the key to preparing highly efficient CdTe-based solar cells (SCs). With CdSe prejunction doping, the diffusion distance via the non-in situ Se doping method is restricted, and the doping ions are difficult to completely diffuse through the whole absorber layer. Moreover, the commonly used p-type back contact material CuSCN shows efficient copper doping characteristics, but the S element is not an ideal doping source for the CdTe absorber. Thus, it is demanding to develop new materials with dual activation of copper and Se. In this paper, on the one hand, CuSeCN was used as a Se doping source on the back surface of the absorber to successfully form p-CdSeTe with a band gap of 1.438 eV. On the other hand, as an emerging copper-treated material, CuSeCN is able to enhance the carrier extraction rate and lower the Schottky barrier of the device, which exhibits similar hole activation performance to CuSCN. In addition, CdTe thin-film devices treated with CuSeCN exhibit higher PCEs than those of devices treated with a CuSCN/CdSe double layer. After optimizing the experimental conditions, the short current density of CuSeCN-doped CdTe thin-film solar cells increased from 28.03 to 30.02 mA/cm, the FF increased from 58.11 to 70.06%, and the power conversion efficiency was 17.48%. These results confirmed that CuSeCN is a promising candidate for both efficient carrier doping and lowering the band gaps of CdTe-based SCs.
拓宽吸收层中合金化的CdSeTe区域是制备高效碲化镉基太阳能电池（SCs）的关键。采用CdSe结前掺杂时，通过非原位硒掺杂方法的扩散距离受限，掺杂离子难以完全扩散穿过整个吸收层。此外，常用的p型背接触材料CuSCN具有高效的铜掺杂特性，但硫元素并非碲化镉吸收层的理想掺杂源。因此，开发具有铜和硒双重激活作用的新材料很有必要。在本文中，一方面，CuSeCN被用作吸收层背面的硒掺杂源，成功形成了带隙为1.438 eV的p-CdSeTe。另一方面，作为一种新兴的铜处理材料，CuSeCN能够提高载流子提取率并降低器件的肖特基势垒，其空穴激活性能与CuSCN相似。此外，用CuSeCN处理的碲化镉薄膜器件的光电转换效率（PCEs）高于用CuSCN/CdSe双层处理的器件。优化实验条件后，CuSeCN掺杂的碲化镉薄膜太阳能电池的短路电流密度从28.03增加到30.02 mA/cm，填充因子从58.11%增加到70.06%，功率转换效率为17.48%。这些结果证实，CuSeCN是实现高效载流子掺杂和降低碲化镉基太阳能电池带隙的有前途的候选材料。
