Replacing the traditional CdS buffer layer with more environmentally friendly materials is an urgent issue for environment‐friendly CZTSSe solar cells. Herein, a nontoxic, flexible, and conductive organic molecular semiconductor PCBM to replace CdS is used and a Cd‐free CZTSSe solar cell is obtained. By introducing mild spin‐coated ZnO window layers, the damage of PCBM in conventional sputtering ZnO process is effectively avoided, and a higher efficiency than previously reported organic semiconductor buffer layer systems and comparable to CdS buffer layer devices are achieved. The flexible PCBM covers the surface of the CZTSSe absorber layer densely and forms a flatter film surface, which is beneficial for the following ZnO deposition. The CZTSSe/PCBM interface exhibits a typical “spike‐like” energy band alignment with a conduction band offset value of only 0.1 eV. Compared with CZTSSe/CdS interface, the CZTSSe/PCBM heterojunction possesses larger interfacial recombination resistance and a longer carrier lifetime. The ideal coating ability, suitable energy band alignment, as well as the better interface carriers transfer behavior suggest that the organic molecular semiconductors can be used instead of the CdS buffer layer to pave the way for truly environment‐friendly kesterite photovoltaic devices.

铜锌锡硫硒薄膜太阳能电池是低成本、有潜力的新型太阳能电池,其吸收层的质量决定太阳能电池器件的性能.溶液法是通过将预制膜硒化热处理来获得铜锌锡硫硒太阳能电池的吸收层材料,其中硒化处理是得到高质量吸收层的重要手段.为得到高质量吸收层,对硒化条件进行设计,分别从硒化程序组成(一步/两步硒化)、硒化温度及硒化时间 3 个方面探究了硒化过程对铜锌锡硫硒吸收层的相纯度、微观形貌及光电转换性能的影响.利用最优硒化参量制备电池器件,获得了 5.72%的光电转换效率.

Permanent preservation of data is essential for massive information recording. Combination of semiconductor with plasmonic nanoparticles has been applied in multicolor display and high-density optical storage. However, bidirectional electron transfer occurs at the Schottky interface under UVA irradiation, resulting in reversible photochemical reaction, information erasure, low recording efficiency and writing rate. To address these issues, a novel Schottky heterostructure of Ag/Ta2O5 modified with alkali halide is developed to realize photoinduced one-directional electron transfer from metal to semiconductor. The recorded information in such a medium of KCl-Ag/Ta2O5 presents excellent holographic storage stability even under exposure of a strong UVA ray (360 nm, 385 mW/cm2). Meanwhile, grating growth rate and efficiency are significantly enhanced by optimizing Ag particle distance and Cl− anion loading amount. This work provides an important strategy for fast and persistent data storage.