With an eye toward improving the efficiency and affordability of solar cells, physicists from the University at Buffalo and Rensselaer Polytechnic Institute (RPI) will develop light-harvesting films using funds from the U.S. Department of Energy SunShot Initiative.
BaZrS3, a synthesized perovskite material, is shown in powder and thin film form (center). To the left is the crystal structure of BaZrS3, and to the right is a schematic of a thin film solar cell incorporating perovskite as the light absorber.(Credit: Yiyang Sun)
The study will focus on a class of promising materials: chalcogenide perovskites, which are nontoxic, earth-abundant compounds whose electronic properties make them ideal for cultivating energy from the sun. The idea is to incorporate this material into solar cells as thin films that absorb and convert sunlight into usable electricity.
“Our long-term goal is to leverage the unique qualities of chalcogenide perovskites to produce solar cells that are not only highly efficient, but also able to be manufactured at a low cost at a commercially viable scale,” said principal investigator Hao Zeng, PhD, a professor of physics in UB’s College of Arts and Sciences.
The research team, funded by a $225,000 SunShot award, also includes co-principal investigators Shengbai Zhang, PhD, Kodosky Senior Constellation Professor at RPI, and Yiyang Sun, PhD, research scientist at RPI.
The SunShot Initiative, part of the DOE’s Office of Energy Efficiency and Renewable Energy, seeks to reduce the cost of solar electricity to be competitive with other energy sources by the end of the decade. The objective is to drive down the cost of solar electricity to $0.06 per kilowatt-hour or $1 per watt (not including incentives).
Searching for inexpensive, environment-friendly and air-stable absorber materials for thin film solar cells has become a key thrust of photovoltaics (PV) research, and the UB-RPI project to develop chalcogenide perovskites for solar cells supports this goal.
Chalcogenide perovskites are a novel class of semiconductors. Sharing some similarities to the widely researched halide perovskites, and unlike most conventional semiconductors, chalcogenide perovskites are strongly ionic. This characteristic is expected to provide intrinsic defect properties favorable for charge transport in PV absorbers.
The team will develop techniques for fabricating thin films made from chalcogenide perovskites. Guided by first-principles computation, the researchers will optimize the electronic and optical properties through defect engineering.
The material’s PV-related properties, such as band gap, carrier mobility and optical absorption, will be studied to pave the way for further integration of these materials into solar cell devices.