Researchers used single-particle observations to monitor structural changes in individual perovskite crystals in response to light irradiation. They found that mixed-halide perovskites, in particular, exhibited crystal destruction and self-healing behaviors. The self-healing mechanism was attributed to a dynamic equilibrium state, in which the crystals bypassed the destruction phase by storing energy in the form of charges in metallic Pb0 regions. This energy was utilized to restore the crystals to their original state.
The researchers also studied the photocatalytic hydrogen production activity of perovskites under visible-light irradiation. They found that mixed-halide perovskites exhibited higher photocatalytic activity than single-halide perovskites, which was attributed to light-induced phase segregation. The photocatalytic activity of the perovskites was stable even after initial light irradiation, suggesting that the damaged perovskites remained active during the self-healing reactions.
The study highlights the potential of perovskites as efficient energy-harvesting materials, particularly in biomass applications. The self-healing mechanism of perovskites can be likened to the process of deciduous trees, where energy is stored during dormancy and utilized during bud break. This biomimicry strategy has potential applications in the development of sustainable energy technologies.