Fabrication of doped SmBaCo₂O_5+δ double perovskites for enhanced solar-driven interfacial evaporation

As a promising solar-thermal energy conversion system, solar-driven vapor generation has been considered as a potential strategy to mitigate freshwater shortage and water contamination. Although remarkable advances have been achieved in this emerging field, the majority of solar evaporators that have been explored suffer from high cost, tedious synthetic protocols, and low robustness. Herein we demonstrate a facile two-step strategy for the synthesis of doped SmBaCo₂O_5+δ double perovskites by combining a sol-gel approach with high-temperature annealing. It is noteworthy that as-prepared double perovskites exhibit an outstanding broadband solar absorption of 93% as well as a relatively low thermal radiation loss compared to conventional carbon-based sunlight absorbers. The constructed double perovskite-based interfacial solar steam device reveals an impressive evaporation efficiency of 86% at a power density of 2 W/cm². Therefore, the explored solar evaporation system based on double perovskites Sm_0.7Sr_0.3BaCo₂O_5+δ offers a complementary approach for large-scale fabrication, high-reliability, and superior performance solar-to-thermal energy conversion systems.