Synthesis of MoSe2/CoSe2 Nanosheets for NIR‐Enhanced Chemodynamic Therapy via Synergistic In‐Situ H2O2 Production and Activation

Currently, the limited intratumoral H2O2 level restricts the development of chemodynamic therapy (CDT). Herein, MoSe2/CoSe2@PEG nanosheets are prepared to reveal NIR‐photocatalytic H2O2 generation to insure the intracellular H2O2 supplement. The formation mechanism is investigated, showing the dissolved O2 and photo‐excited electrons to determine H2O2 production via sequential single‐electron transfer process. The experimental data and density functional theory calculation further display their typical‐II heterostructure, which possesses the effective charge separation and nearly four times H2O2 generation than MoSe2@PEG. In addition, the nanocomposites also reveal the peroxidase/catalase activity, making the in‐situ H2O2 activation and ·OH generation. And, the O2 production derived from catalase‐mimic activity not only relieves hypoxia but also offers the source for H2O2 production. Because of the decreased resistance for charge transfer, MoSe2/CoSe2@PEGs also reveal more than three times enzyme‐activity for MoSe2@PEG. With the narrow band gap and high NIR‐harvest, MoSe2/CoSe2@PEG exhibits the great photothermal converting ability (62.5%). MoSe2/CoSe2@PEG reveals the novel biodegradation, and most of them can be eliminated via urine and feces within 2 weeks. Here, the computed tomography/magnetic resonance imaging/photothermal imaging and the synergistic photothermal therapy/CDT treatments further make sure potential application on anticancer. Inspired by photocatalysis, the MoSe2/CoSe2@PEG nanosheets are synthesized to bring about intracellular NIR‐triggered H2O2 generation. Their nanozyme activity also ensures in‐situ activation of H2O2 to improve chemodynamic therapy. Moreover, the effective charge separation and transfer of nanoheterostructures further enhance photocatalytic (four times) and enzyme‐activity (three times) than pure MoSe2@PEG.