Solvothermal Assembly of RGO-Decorated CdTe Nanocrystal Heterojunctions for Enhanced Visible-Light Photocatalysis

Interfacial charge recombination severely limits the photocatalytic efficiency of CdTe. Herein, a reduced graphene oxide (RGO)-CdTe nanocrystal heterojunction is rationally constructed via a one-pot solvothermal strategy to regulate charge carrier dynamics. The two-dimensional conductive RGO scaffold enables intimate interfacial contact and acts as an efficient electron acceptor, promoting rapid charge extraction and suppressing recombination, as confirmed by photoluminescence quenching and enhanced photocurrent response. The optimized composite exhibits markedly improved visible-light photocatalytic activity, achieving 91.8% degradation of methylene blue within 90 min. The degradation proceeds through the formation of reactive species, yielding smaller intermediates and partially mineralized products. Moreover, the catalyst demonstrates excellent stability with minimal activity loss over multiple cycles. Mechanistic analysis indicates that the enhanced performance originates from accelerated interfacial electron transfer and prolonged carrier lifetime, enabling efficient generation of reactive oxygen species. This work provides a facile one-pot solvothermal strategy for engineering graphene-mediated heterojunctions toward high-efficiency environmental photocatalysis.