Gabriel J. Man

Congratulations to Gabriel Man, Zuckerman Postdoctoral Scholar (Alumn), on the recent publication of a paper in  Cornell University’s arxiv, which  examines whether perovskites could realistically enable the next generation of ultra-efficient solar cells.  Dr. Man describes the “ultimate” solar cell, which would combine the highest possible light-to-electricity efficiency with low cost and long lifetime.  In contrast, today’s commercial technologies are fundamentally limited by what is known as the Shockley–Queisser efficiency ceiling.  Metal halide perovskites, a newer class of solar materials, have attracted attention because they are inexpensive to produce and may allow high-energy charges (“hot carriers”) to cool more slowly. These hot-carrier solar cells could, in theory, double that limit in a single device, yet major materials and engineering challenges still prevent them from becoming reality.

Abstract:
History has shown that very few absorber materials develop into viable solar cell technologies, and it has been recognized that given the declining costs of silicon-based technologies, a new material must offer potential for both lower cost and higher efficiencies than the Shockley-Queisser limit. Slow cooling of photocarriers with energy in excess of the band edges (hot carriers), which is the first prerequisite of a solar absorbing material for building a hot carrier solar cell technology, has been reported in perovskites since the 2010s. The goal of this review is to illuminate the path towards a single-junction perovskite hot carrier solar cell technology by emphasizing uncertainties in understanding slow hot carrier cooling and recommending approaches to resolve them.