Publication date: 4th October 2024
The application of solar cells is one of the most promising solutions for satisfying the ever-increasing global energy demand. Recently, organic-inorganic hybrid lead halide perovskite solar cells (PSCs) are receiving considerable attention and have emerged as an extremely promising photovoltaic technology due to their remarkable photovoltaic performance and potentially low production cost. To date, progress has been made on each layer, with major emphasis on perovskite film processing and relevant material design. Consequently, the power conversion efficiency of lead halide perovskite based thin-film photovoltaic devices has already surpassed 26 % [1].
Charge (both, hole and electron) transporting material (CTM) is one of the main factors of PSCs, which determines the cost, energy conversion effectiveness, and stability of the device. However, most CTMs have many disadvantages, including complicated and expensive synthesis, the tendency of self-aggregation, which degrade the quality of the charge transporting layer and reduce device stability and efficiency. Therefore, considerable and continuous efforts have been made to develop more ideal CTMs, which advantages should be as follows: matching well with the valence band and conduction band of the perovskite to enable hole or electron extraction and blocking, minimal absorption in the visible and near infrared regions, sufficient charge mobility, excellent thermal and photochemical stability, high processability, and low cost.
This lecture will cover results of our investigations in the field of molecular engineering of low molecular charge transporting materials for perovskite solar cells. Our group has been successful in creating several classes of novel organic hole and electron transporting materials, which are competitive both in the conventional and in the inverted PSCs. The molecularly engineered new charge transporting materials were synthesized via facile preparation procedures from commercially available and relatively inexpensive starting reagents, resulting in up to several fold cost reduction of the final product compared with well-known reference CTMs.