An in-situ room temperature route to CuBiI4 based bulk-heterojunction perovskite-like solar cells

作者：Zhang, Busheng; Lei, Yan^*; Qi, Ruijuan; Yu, Haili; Yang, Xiaogang; Cai, Tuo; Zheng, Zhi^*

来源：Science China-Materials, 2019, 62(4): 519-526.

DOI：10.1007/s40843-018-9355-0

• copper-bismuth-iodide
• CuBiI4
• room temperature
• lead-free
• perovskite-like
• bulk-heterojunction
• solar cells

Both bismuth and copper are non-toxic and earth-abundant elements suitable for lead-free halide perovskite-like photovoltaic devices. Here, we report a highly facile route for in-situ producing copper-bismuth-iodide (CuBiI4) thin films directly on ITO substrate at room temperature, by utilizing a Bi-Cu alloy layer as precursor. X-ray diffraction and transmission electron microscopy (TEM) results verified the formation of well crystallized CuBiI4 thin films with [222] orientation. The transient photovoltage (TPV) analysis revealed that the CuBiI4 is an n-type semiconductor with a suitable band gap of similar to 1.81 eV, preferable to photoelectric conversion compared with CH3NH3PbI3. It is very interesting that the subsequent spin-coating process of the classical Spiro-MeOTAD organic solution with TBP and acetonitrile resulted in a dense and smooth CuBiI4:Spiro-MeOTAD bulk-heterojunction film. The preliminarily fabricated simple sandwich structures of ITO/CuBiI4:Spiro-MeOTAD/Au hybrid solar cell devices displayed efficient photovoltaic performance with the PCE up to 1.119% of the best sample. The room temperature direct metal surface elemental reaction (DMSER) method may provide a new insight for all-inorganic lead free perovskite-like A(a)B(b)X(x) compounds and high performance photovoltaic devices.

• 出版日期2019-4
• 单位许昌学院; 华东师范大学