Efficient and hysteresis-free mixed-dimensional 2D/3D perovskite solar cells using ethyl lactate as a green additive to perovskite precursor solutions

Due to their remarkable performance and ease of processing in low temperature solutions, organometal hybrid perovskite solar cells (HPSCs) have recently become a hot topic. Current solution processes extensively use hazardous chemicals, such as chlorobenzene, in perovskite and hole-transport material deposition processes. Therefore, the invention of safe and economical solvent technologies is a prerequisite for commercial viability. Herein, ethyl lactate (biodegradable, non-hazardous, and inexpensive solvent) is utilized for the first time as a green solvent to enhance the quality of anti-solvent-assisted solution-engineered perovskite films. The obtained results show that the incorporation of a certain amount of ethyl lactate can produce a homogeneous and highly crystalline perovskite layer with enhanced optoelectronic properties. This method increases the efficiency of 2D/3D tripe-cation HPSCs to 21.78% (against 17.09% for the control cells) with a decreased hysteretic effect and improved moisture stability.