Rational Design of Hybrid Perovskites for Photovoltaic Applications
Research and development into promising low-cost new materials as an alternative to silicon have been attracting increasing attention in the photovoltaic community.
Among a number of initiatives, a relatively young class of materials, namely hybrid organic-inorganic perovskites (HOIPs), has recently achieved remarkable success in photovoltaic devices. In particular, the efficiencies of perovskite solar cells (PSCs) using prototypical lead hybrid perovskites, for example, methylammonium lead iodide (MAPbI3), have soared from less than 4% in 2009 to over 24% by 2019.1
The extraordinary optoelectronic performance of perovskite materials are attributed to their high carrier mobility, long diffusion lengths. In particular, their cost-effective solution processing has opened up the prospect of applications in solar energy.2,3 Despite the intensive research efforts in this area, however, the commercialization of PSCs faces two major challenges:
- the most popular compositions of hybrid lead halide perovskites lack chemical stability.
- The toxic lead content in perovskite devices raises environmental concerns and is problematic for their wide scale deployment.
In this talk, I will discuss our recent efforts on achieving bandgap4 as well as structural tunability in hybrid perovskites5, including using machine-learning to accelerate the materials characterization of multi-site lead-free alloy series,6,7 in the contribution to the development of novel thin-film material systems as an alternative to the current lead iodide perovskites used in PSCs.