A promising step forward in the search for safer and high-performance alternatives to conventional perovskites
Advancing solar energy with chalcogenide perovskites
The photovoltaic industry has recently welcomed a new generation of high-efficiency devices: solar cells based on lead-halide perovskites. These relatively new compounds have achieved remarkable conversion efficiencies in just a few years, rivaling crystalline silicon. Their success is largely due to their optical and electrical properties, including a high absorption coefficient and long carrier lifetimes.
Despite these advantages and rapid progress, issues like poor long-term stability, phase degradation under light, heat, and humidity, and especially lead toxicity continue to limit their commercial scalability.
A viable alternative may come from chalcogenide perovskites. These materials have gained significant attention in recent years as semiconductors with outstanding optoelectronic properties. Composed of non-toxic, abundant, and stable elements, they generally follow the ABX₃ formula, where A is a group II cation (e.g., Ba²⁺, Ca²⁺, Sr²⁺), B is a group IV transition metal ion (e.g., Ti⁴⁺, Zr⁴⁺, Hf⁴⁺), and X is a chalcogen (S, Se).
A new study from the Universidad Autónoma de Querétaro in Mexico focused on one specific chalcogenide: SrHfSe₃. Led by research professor Latha Marasamy, the team highlighted the compound’s superior chemical stability, tunable bandgap, high photon absorption coefficient, and enhanced p-type carrier mobility. These features make it a strong candidate for photovoltaic applications.
Over 1,600 simulated configurations to optimize performance
“We studied chalcogenide perovskite solar cells based on SrHfSe₃ in the FTO/BaSnO₃/SrHfSe₃/HTL/Au architecture, initially using MoS₂ as the hole transport layer (HTL),” wrote Dr. Marasamy in Solar Energy Materials and Solar Cells.
“We then systematically replaced MoS₂ with 40 different HTLs, including inorganic semiconductors, polymers, and MXenes, in what is the first investigation of this kind led by our group.”
The researchers simulated 1,627 configurations, optimizing critical parameters such as absorber–acceptor density and layer thickness under near-realistic conditions. “Our results […] show that, through meticulous device design, chalcogenide perovskites based on SrHfSe₃ can achieve significant performance gains,” the team concluded.
Read the full study: A new class of SrHfSe₃ chalcogenide perovskite solar cells with diverse HTMs: Theoretical modelling towards efficiency enhancement, published in Solar Energy Materials and Solar Cells (2025).