ScholarWorks@성균관대학교

초록

Layered double hydroxides (LDHs) with tunable structures and redox properties hold promise for supercapacitors (SCs) and urea electrooxidation. This study proposes a simple, cost-effective coprecipitation method to synthesize Ni-incorporated CoV LDH. Although CoV LDH shows potential as an electrode material, its poor conductivity and structural instability in alkaline media limit its performance. Incorporating Ni enhances electrochemical properties by modifying the host structure and generating new active sites. Initially, CoV LDH is prepared using a binary Co and V system. A one-step Ni incorporation into optimized CoV LDH significantly improves its structural integrity and kinetics. The Ni-CoV LDH coated on nickel foam (NF@CVN3) achieves a high specific capacitance of 508 F g(-1) with 83 % retention after 5000 cycles. An asymmetric supercapacitor (NF@CVN3//NF@AC) delivers an energy density of 21.2 Wh kg(-1) at 801.2 W kg(-1) and retains 95 % capacitance over 5000 cycles. Furthermore, NF@CVN3 shows excellent urea electrooxidation activity with an onset potential of 1.34 V vs RHE to drive a current density of 10 mA cm(-2) and stable operation at a constant potential of 0.5 V for 24 h.

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