Photovoltaic materials facilitate the conversion of sunlight into electricity by harnessing the interaction between light and matter, offering an eco-friendly and cost-efficient energy solution. Combining data-driven approaches with static and time-dependent density-functional theories and nonadiabatic molecular dynamics simulations, we predict 14 high-performance photoabsorber materials from a family of known quaternary semiconductors. Among these, we investigate four compounds—$\mathrm{Sr}\mathrm{Cu}\mathrm{Gd}\mathrm{Se}$${}_3$, $\mathrm{Sr}\mathrm{Cu}\mathrm{Dy}\mathrm{Te}$${}_3$, $\mathrm{Ba}\mathrm{Cu}\mathrm{La}\mathrm{Se}$${}_3$, and $\mathrm{Ba}\mathrm{Cu}\mathrm{La}\mathrm{Te}$${}_3$—in greater detail. Their crystal structures reveal that $\mathrm{Cu}$ and $\mathrm{Gd}$/$\mathrm{La}$/$\mathrm{Dy}$ possess tetrahedral and octahedral coordination environments, respectively. Such bonding features suggest that these materials would possess optical activity, defect tolerance, and stability complementary to the known high-performance photoabsorber materials with either tetrahedral (e.g., $\mathrm{Si}$, $\mathrm{Ga}\mathrm{As}$, $\mathrm{Cd}\mathrm{Te}$) or octahedral (e.g., methylammonium lead iodide) coordination chemistries. Hybrid density-functional theory calculations including spin-orbit coupling reveal that $\mathrm{Sr}\mathrm{Cu}\mathrm{Gd}\mathrm{Se}$${}_3$, $\mathrm{Sr}\mathrm{Cu}\mathrm{Dy}\mathrm{Te}$${}_3$, $\mathrm{Ba}\mathrm{Cu}\mathrm{La}\mathrm{Se}$${}_3$, and $\mathrm{Ba}\mathrm{Cu}\mathrm{La}\mathrm{Te}$${}_3$ possess direct band gaps of 1.65, 1.01, 1.79, and 1.05 eV, respectively. These band-gap values lie close to an optimal range ideal for visible-light absorption. Consequently, the calculated optical absorption coefficient and spectroscopic limited maximum efficiency for these compounds become comparable to, or larger than, those of crystalline silicon, $\mathrm{Ga}\mathrm{As}$, and methylammonium lead iodide. The calculated exciton binding energies for these compounds are relatively small (9–80 meV), signifying easy separation of the electron-hole pairs and hence enhanced power-conversion efficiencies. Investigations of photoexcited carrier dynamics reveal a relatively long carrier lifetime (approximately 30–40 ns), suggesting suppressed nonradiative recombination and enhanced photoconversion efficiencies. Temperature-dependent structural dynamics and electronic band energies reveal relatively low local structural fluctuation, signifying their high stability and small electronic-ionic sublattice coupling, leading to a weaker nonradiative recombination process for photogenerated charge carriers, which is beneficial for high-performance photovoltaics. We have further determined the defect-formation energies in these compounds, which show that despite the likely formation of cation vacancy and antisite defects, midgap states remain absent, making these defects nondetrimental to carrier recombination. Our theoretical predictions invite experimental verification and encourage further investigations of these and similar compounds in this quaternary-semiconductor family.

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• Carrier dynamics
• Defects
• Optoelectronics
• Chalcogenides
• Photovoltaic absorbers
• Ab initio molecular dynamics
• High-throughput calculations
• Time-dependent DFT