钙钛矿太阳能电池的稳定性

The stability of perovskite solar cells

有机-无机卤化物钙钛矿太阳能电池的研究在近几年里获得了极大的突破.然而,电池长期的稳定性和重金属铅的毒性等问题仍未得到完全解决.本文将讨论钙钛矿太阳能电池稳定性的影响因素,从器件结构方面入手分析钙钛矿材料、空穴传输材料、电子传输材料以及电极对钙钛矿电池稳定性的影响,然后根据不同结构中影响电池稳定性的因素提出对应的解决方案,从而提升钙钛矿太阳能电池稳定性.最后,我们提出由n型半导体层、绝缘层和p型半导体层依次层叠构成的全无机介孔p-i-n结构框架有助于钙钛矿电池的稳定性.

Solar energy as a widespread clean energy is considered to be the key to solving future energy problems,solar cell technology is also evolving,of which perovskite solar cells because of its rapid growth efficiency gains wide attention.The great breakthroughs have been observed in organic-inorganic halide perovskite solar cells.However,the long-term stability due to decomposition and the toxicity of heavy metal lead have not been perfectly solved.Solving the stability problem will be the key to the future application of perovskite solar cells.This review focuses the factors affecting the stability of perovskite solar cells from the perspective of perovskite solar cell structure,including perovskite materials,hole transport materials,electron transport materials,and electrodes.Through the analysis we found that for perovskite materials,grain size and defect density affect the stability of perovskite.The grain with large size will inhibit the defect state,improve the stability of the device.Moisture,oxygen and light will promote the decomposition process of perovskite,even in the case of isolated air.The thermal stability of perovskite is also poor and will be self-decomposition at a certain temperature.While perovskite will also have the problem of crystal structure instability,the perovskite may changes to the non-perovskite phase,which will result in a sharp attenuation of efficiency.The dopant in the hole transport material may cause destruction and decomposition of the perovskite structure.The titanium dioxide commonly used in electron transport materials can lead to the decomposition of perovskite and the reduction of electron transport efficiency due to oxygen vacancy and strong electron extraction.Silver and aluminum commonly used in electrode will be associated with the perovskite layer formation of halide,which may reduce the conductivity of the electrode and destroy the perovskite structure.In order to solve the above problems,we propose that new preparation should be developed to get thin films with large grain size.The researchers also should find new perovskite material insensitive to moisture and oxygen,appropriate package to isolate the air from the water and oxygen.The inorganic perovskite materials with enhancing thermal stability of the perovskite film should be considered to improve the stability of perovskite solar cells.Developing organic hole transport materials that do not require additives or inorganic hole transport materials can reduce the possibility of perovskite crystals being destroyed by hole transport materials.Avoid direct contact between perovskite and titanium dioxide or use other electron transport materials instead of titanium dioxide to prevent the decomposition of perovskite.Furthermore,we recommend mesoscopic framework based on all inorganic metal oxides for organic-inorganic perovskite based photoelectric conversion devices.