Polycrystalline silver bismuth iodide (SBI) powders of various compositions (Ag : Bi = 2 : 1–1 : 1 in atomic ratio) were synthesized via a solid-state reaction in an evacuated Pyrex tube. Regardless of the composition of Ag and Bi, Ag₂BiI₅ in the hexagonal phase was preferentially formed and BiI₃ impurity in the rhombohedral phase was formed with the increase of the Bi component. The synthesized SBI powders of various compositions were applied as light absorbers for hybrid solar cells (HSCs), which employ mesoporous TiO₂ as the electron transporting layer and pristine spiro-OMeTAD as the hole transporting layer. To deposit light absorber layers, the coating solutions were prepared by dissolving the synthesized SBI powders in DMSO/DMF/HI and spin-coated over the mesoporous TiO₂ layer. For the solar cell employing pure Ag₂BiI₅, a photovoltaic conversion efficiency (PCE) of 1.74% was achieved, whereas the inclusion of the BiI₃ impurities in the Ag₂BiI₅ phase significantly increased the device performance. The highest PCE of 2.31% was achieved with the SBI of Ag : Bi = 55 : 45. Furthermore, the SBI solar cells show no hysteresis in the J–V curve measurements and are highly stable under ambient conditions, exhibiting excellent long-term stability at a relative humidity of 50%.

中文翻译：

---

各种成分的碘化银铋作为混合太阳能电池的潜在无铅光吸收剂

在抽空的Pyrex管中通过固态反应合成了各种成分（Ag：Bi = 2：1-1：1：1原子比）的多晶碘化铋银（SBI）粉末。不论Ag和Bi的组成如何，随着Bi成分的增加，优先形成六方相的Ag ₂ BiI ₅，而在菱面相中形成BiI ₃杂质。将合成的各种组成的SBI粉末用作混合太阳能电池（HSC）的光吸收剂，该混合太阳能电池采用中孔TiO ₂作为电子传输层，原始的螺-OMeTAD作为空穴传输层。为了沉积光吸收剂层，通过将合成的SBI粉末溶解在DMSO / DMF / HI中并旋涂在中孔TiO ₂层上来制备涂料溶液。对于采用纯Ag ₂ BiI ₅的太阳能电池，实现了1.74％的光电转换效率（PCE），而在Ag ₂ BiI ₅相中包含BiI ₃杂质则显着提高了器件性能。Ag的SBI：Bi = 55:45时，PCE最高，达到2.31％。此外，SBI太阳能电池在J – V中没有滞后现象 曲线测量，在环境条件下高度稳定，在50％的相对湿度下具有出色的长期稳定性。