The inorganic CsPbI₃ perovskite obtained from dimethylammonium iodide (DMAI)-related strategies have greatly promoted the development of CsPbI₃ perovskite solar cells (PSCs). However, deeper understandings are urgently needed to further enhance device performance. Herein, the crystallization processes of DMAI-based strategy are systematically studied and some new understandings are proposed. During annealing, β-phase-like CsPbI₃ is first formed and then gradually transits to γ-phase-like structure. DMA ions tend more to form DMAPbI₃ in the system, implying the amount of alloyed DMA ions in CsPbI₃ would be very limited. In addition, the pre-generated Cs₄PbI₆ plays an important role in stabilizing CsPbI₃ perovskite phase at low temperature. These findings help us to finely manipulate film composition, and the quality of CsPbI₃ film is substantially improved after simultaneously suppressing the formation of δ-CsPbI₃, minimizing DMAPbI₃ residual and generating PbI₂ passivator. More promisingly, the carbon-based CsPbI₃ PSCs without hole transporter achieve a record efficiency of 14.6%.

从二甲基碘化铵（DMAI）相关策略获得的无机CsPbI ₃钙钛矿极大地促进了CsPbI ₃钙钛矿太阳能电池（PSC）的发展。但是，迫切需要更深入的了解，以进一步提高设备性能。在此，系统地研究了基于DMAI的策略的结晶过程，并提出了一些新的认识。在退火过程中，先形成β相的CsPbI ₃，然后逐渐转变为γ相的结构。DMA离子趋于更形成DMAPbI ₃在系统中，这意味着在CsPbI合金DMA离子的量₃将是非常有限的。另外，预先生成的Cs₄ PbI ₆在低温下稳定CsPbI ₃钙钛矿相中起着重要作用。这些发现有助于我们精细地控制膜组成，并且在同时抑制δ- CsPbI ₃的形成，最小化DMAPbI ₃残留并生成PbI ₂钝化剂之后，CsPbI ₃膜的质量得到了显着改善。更令人鼓舞的是，不带空穴传输剂的碳基CsPbI ₃ PSC实现了14.6％的创纪录效率。