采用PEABr添加剂获得高效且稳定的碳基CsPbBr_(3)太阳能电池

Efficient and stable carbon-based CsPbBr_(3) solar cells added with PEABr additive

全无机CsPbBr_(3)钙钛矿材料因其本征稳定性好、成本低廉从而在光伏领域展现出巨大的应用潜力,但目前CsPbBr_(3)太阳能电池的光电转换效率仍远低于其他体系的钙钛矿太阳能电池.本文以无空穴传输层结构的碳基CsPbBr_(3)全无机钙钛矿电池作为研究对象,以多步旋涂法为基础,通过在PbBr_(2)(DMF)溶液中添加2-苯乙胺溴盐(PEABr)来调控CsPbBr_(3)薄膜的结晶质量,降低薄膜缺陷态密度,钝化晶粒间界,并对其中的关键工艺参数包括CsBr的用量(旋涂次数)、旋涂PbBr_(2)薄膜时的衬底预热温度以及退火温度进行了优化.最终在大气环境下获得了兼具稳定和高效的无空穴传输层结构的碳基CsPbBr_(3)太阳能电池,器件的光电转换效率达到8.25%,并在无封装条件下保存1500 h仍可保持90%以上的效率,对于进一步拓展CsPbBr_(3)钙钛矿电池的优化设计思路具有重要意义.

In recent years,organic-inorganic hybrid perovskite solar cells have become a research hotspot in the photovoltaic field because of their excellent power conversion efficiency.However,this hybrid perovskite material’s intrinsic instability and the harsh preparation environment limit its further commercial application.All-inorganic CsPbBr_(3)perovskite materials have attracted much attention because of their good stability,low cost and can be prepared in an atmospheric environment,showing great application potential.The controllable preparation and growth kinetics of CsPbBr_(3)materials need to be further studied,and the conversion efficiency of photovoltaic devices is still low.Considering the instability caused by traditional organic hole transport materials and their high preparation cost,this work focuses on the systematical studies of CsPbBr_(3)all-inorganic perovskite cells without a hole transport layer.Growth kinetics material of CsPbBr_(3)is controlled by adding 2-phenylethylamine bromide to precursor solution.The main research contents and results are described as follows.Based on multi-step spin-coating preparation of CsPbBr_(3)perovskite films,the perovskite cell preparation method is studied,and the critical process parameters including the spin-coating PbBr_(2),amount and number of spin-coating of CsBr,substrate preheating temperature,and the annealing temperature,are optimized.The optimization tests show that the optimal spin-coating of CsBr is obtained by being optimized five times and the spin-coating PbBr_(2)is conducted in the atmospheric environment.The optimal preheating temperature of the substrate is 80℃,and the optimal annealing temperature is 100℃.The perovskite films prepared under this condition are compact,each with a continuous high phase purity and good crystallization performance.The PbBr_(2)in DMF is first adopted and the 2-phenylethylamine bromide(PEABr)solution is added to regulate the CsPbBr_(3)crystalline quality of the film.The effects of PEABr on the perovskite crystallization process and device performance are systematically investigated.The results show that the introduction of PEABr can effectively optimize the CsPbBr_(3).The crystalline properties of the two-dimensional perovskite materials can improve the grain boundaries and improve their transport properties.The prepared perovskite solar cell with PEABr shows the highest power conversion efficiency of 8.25%,and it can maintain the efficiency of more than 90%when being stored for 1500 h under the condition of no encapsulation.Finally,stable,efficient and low-cost all-inorganic CsPbBr_(3)solar cells without a hole layer are obtained.