QAZAQ GREEN.  A research team from Helmholtz-Zentrum Berlin (HZB) and the University of Potsdam has identified major differences in ion behaviour across several leading perovskite semiconductor compounds. The study shows that tin-based perovskites manufactured with an alternative solvent contain ten times fewer mobile ions than conventional lead perovskites — a result that could unlock far more stable and environmentally benign perovskite solar cells.

Perovskite photovoltaics have advanced rapidly over the past decade, with lead-based devices reaching efficiencies above 27%. Yet issues remain: lead is toxic, and the materials degrade over time due to migrating halide ions. The new analysis highlights why tin-based perovskites — so far less explored — may offer a more resilient pathway for next-generation solar technologies.

Researchers examined four widely used perovskite compositions, measuring both ion density and ion migration. The tin perovskites produced in HZB’s Hysprint laboratory showed the lowest concentration of mobile ions and degraded five times more slowly than lead-based materials. A particularly promising result came from a tin perovskite synthesized with an alternative DMF-DMI solvent. This sample contained an order of magnitude fewer mobile ions than its lead counterpart and demonstrated stable operation for more than 600 hours.

The findings suggest that the longstanding efficiency gap between tin- and lead-based perovskites may be linked to limited research rather than fundamental material constraints. Tin is non-toxic, and theoretical models indicate it could enable even higher efficiencies.

According to Dr Artem Musiienko, who leads the HZB research group, the results make a strong case for prioritizing tin-based perovskite research. The team says controlling ion migration in these materials opens the way to stable thin-film solar cells with significantly improved long-term performance.