Designed synthesis of zeolitic imidazolate framework derived Ag and S co-doped multi-metal layered double hydroxide for high-performance supercapacitors and zinc batteries

Layered double hydroxides (LDHs) are promising cathode active materials for aqueous rechargeable devices. However, their electrochemical activity, kinetics, and stability should be further improved to meet the high application demands. Herein, an efficient composition and structure co-regulation strategy is applied to optimize and enhance the electrochemical performance of LDH-based cathodes. CoMn-based metal-organic framework is employed as templates to fabricate C and N co-doped NiCoMn-based layered double hydroxide with Ag and S adulterated. The adulteration of Ag and S dramatically enhances the electrical conductivity, the interactions with electrolyte, and the electron transfer activity. Moreover, the designed layered structure could also facilitate the charge carrier and electron transfer. Thus, the electrochemical activity, kinetics, and stability could be ameliorated. Experimental, theoretical, and simulation researches are performed to investigate the electrochemical performance and reveal the improvement mechanism. The cathode renders an admirable specific capacity of 328.5 mAh·g⁻¹ (1880.7 F·g⁻¹) and superb cycle life of 90.4 % capacity retention rate after 10,000 cycles. The corresponding assembled hybrid supercapacitor and zinc battery possess satisfactory energy density, power density, and cycling stability.