Electrical engineering

Nanotechnology

Energy conversion efficiency

Chalcogenide

Photovoltaics

Absorption (acoustics)

Semiconductor

Engineering

Perovskite (structure)

Band gap

Composite material

Halide

Inorganic chemistry

Chemistry

Materials science

Photovoltaic system

Chemical engineering

Optoelectronics

Advanced Energy Materials

Solar cells with organic‐inorganic lead halide perovskites have achieved great success and their power conversion efficiency (PCE) has reached to 22.1%. To address the toxicology of lead element and some stability issues associated with the organic‐inorganic lead halide perovskites, inorganic lead‐free perovskites have gained more attentions from the photovoltaic research community. Herein, a series of chalcogenide perovskites are proposed as optical absorber materials for thin‐film solar cells. SrSnSe 3 and SrSnS 3 are predicted to be direct bandgap semiconductors with the bandgap value being within the optimal range of 0.9–1.6 eV. Both SrSnSe 3 and SrSnS 3 not only exhibit good optical absorption properties and carrier mobility, but also possess flexible bandgaps that can be continuously tuned within the grange of 0.9–1.6 eV via the element‐mixing strategy, thereby render both perovskites as promising candidates for photovoltaic applications.

Perovskite Chalcogenides with Optimal Bandgap and Desired Optical Absorption for Photovoltaic Devices