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Fabrication of versatile hydrogels in a facile and effective manner represents a pivotal challenge in the field of biomaterials. Herein, a novel strategy is presented for preparing on‐demand degradable hydrogels with multilevel responsiveness. By employing selenol‐dichlorotetrazine nucleophilic aromatic substitution (SNAr) to synthesize hydrogels under mild conditions in a buffer solution, the necessity of additives or posttreatments can be obviated. The nucleophilic and redox reactions between selenol and tetrazine culminate in the formation of three degradable chemical bonds—diselenide, aryl selenide, and dearomatized selenide—in a single, expeditious step. The resultant hydrogel manifests exceptional adaptability to intricate environments in conjunction with self‐healing and on‐demand degradation properties. Furthermore, the resulting material demonstrated light‐triggered antibacterial activity. Animal studies further underscore the potential of integrating metformin into Se‐Tz hydrogels under green light irradiation, as it effectively stimulates angiogenesis and collagen deposition, thereby fostering efficient wound healing. In comparison to previously documented hydrogels, Se‐Tz hydrogels exhibit controlled degradation and drug release, outstanding antibacterial activity, mechanical robustness, and bioactivity, all without the need for costly and intricate preparation procedures. These findings underscore Se‐Tz hydrogels as a safe and effective therapeutic option for diabetic wound dressings. [ABSTRACT FROM AUTHOR]

• Chlorella incorporated into hydrogels for continuous oxygen and bioelectric delivery. • Hydrogels offer mechanical support and create optimal microenvironment for Chlorella. • Hydrogels improve diabetic wound healing by enhancing proliferation and angiogenesis. Electrical stimulation and oxygen are vital for promoting cell proliferation, migration, and differentiation to repair damaged tissues in chronic wound healing in patients with diabetes. The effective oxygen production by Chlorella has garnered attention in the medical field, but the potential of extracellular electron production in skin repair has not been explored. Inspired by this, we developed CHPS hydrogels, a composite of polyacrylamide and sodium alginate, with Chlorella loaded in a semi-interpenetrating network. This network is formed by crosslinking acrylamide initiated by free radicals, with alginate chains dispersed within the network. When applied to wounds, CHPS hydrogels effectively protect damaged tissue, provide mechanical support to Chlorella against external forces, and create an optimal artificial microenvironment to promote the proliferation of Chlorella. Our study demonstrated that CHPS hydrogels exhibit remarkable fracture elongation and adhesion properties and continuously produce oxygen and bioelectrical currents through photosynthesis. Furthermore, the sustained release of dissolved oxygen and bioelectricity by CHPS hydrogels significantly enhances cell proliferation, migration, and angiogenesis, leading to improved wound healing in diabetic mice. These findings provide compelling evidence for further exploration of CHPS hydrogels as a cost-effective, simple, and accessible strategy for enhancing the clinical treatment of chronic wounds in diabetic patients. [ABSTRACT FROM AUTHOR]