Chinese Journal of Environmental Engineering•2026•DOI: 10.12030/j.cjee.202509078
The rapid expansion of photovoltaic (PV) installations and the impending retirement of early-stage modules have made the recycling of end-of-life PV modules an urgent issue. This review systematically examines the types and structures of retired PV modules, with a focus on crystalline silicon (c-Si) and thin-film technologies. It critically evaluates the principles, processes, and pros and cons of physical, chemical, pyrolysis, biological, combined, and emerging methods for recovering c-Si modules. The current status of silicon, metal, and valuable component recovery processes is summarized. For thin-film modules, the core technologies for recovering valuable components via pyrometallurgical, hydrometallurgical, biological, and novel approaches are analyzed in depth. Results indicate that conventional methods (physical, chemical, pyrolysis) remain dominant but suffer from high energy consumption, pollution, and chemical usage. Emerging technologies such as biological and green leaching are identified as key research directions, though they face challenges of low technical maturity and high costs. Finally, policy orientations and existing challenges are discussed, and future development directions are proposed, providing significant guidance for the sustainable and large-scale green development of the PV industry.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4123-0
Aqueous aluminum-ion batteries (AAIBs) are promising for large-scale energy storage due to safety, sustainability, and theoretical high capacity. However, sluggish electron/ion transport in conventional cathodes limits rate capability. Here, we first propose high-entropy engineering of metal oxides (HEOs) as cathodes in AAIBs, leveraging the 'cocktail effect' and abundant electron transport pathways to enhance rate-capacity. Atomic-level interactions between different metal atoms broaden the d-band with reduced electronic level degeneracy, facilitating rapid electron transport, achieving one of the best rate capabilities (119.4 mAh g−1 at 10.0 A g−1) among metal-oxide cathodes. The disordered layered oxides formed with a high-entropy framework alleviate electrostatic repulsion between aluminum ions and the fixed lattice, mitigating structural degradation and imparting excellent cycling stability (over 95.1 mAh g−1 after 500 cycles at 2.0 A g−1). The optimized HEO-Cr cathode (Fe0.6Co0.6Ni0.6Mn0.6Cr0.6O4) exhibits outstanding rate performance and cycling stability. DFT simulations and electrochemical tests reveal that multi-transition metal incorporation, bandgap narrowing, and unique lattice structure drastically enhance electron transport efficiency. The layered phase formed after cycling, based on a high-entropy framework, overcomes challenges from high charge density aluminum ions, significantly enhancing cycling stability. This work paves the way for high-performance AAIBs and other aqueous multivalent metal ion batteries by rationally designing high-entropy engineering.