Enhanced interfacial charge transfer via in-situ construction of integrated NiO/NiCo2O4 heterojunction coupled with carbon layer for high-performance supercapacitor and photocatalysis

Abstract

Constructing heterostructured composites presents a promising approach to enhance both electrochemical and photocatalytic performance. However, the low interfacial charge transfer efficiency caused by lattice mismatch severely hinders its potential application. Herein, integrated NiO/NiCo2O4 heterostructure with dodecahedral structure has been facilely prepared by a one-step in situ calcination method. In addition, to further promote the yield of photogenerated electrons and enhance electrochemical reaction kinetics, a carbon layer for charge transport is incorporated onto the outer shell of NiO/NiCo2O4 heterostructured. The elaborate designed and constructed integrated C1.0 @NiO/NiCo2O4 heterojunctions with efficient interfacial charge transfer channels exhibit an excellent gravimetric specific capacitance of 588 F g−1 at 1 Ag−1 for three electrode cell. Moreover, the C1.0 @NiO/NiCo2O4//AC supercapacitor has an excellent energy density of 68.13 Wh kg−1 at a high power density of 750 W kg−1, delivering a retention rate of capacitance exceeding 91.4% over 10000 cycles. The visible-light-induced degradation efficiency of rhodamine B (RhB) was determined to be 83.68% within a duration of 120 min. And a probable mechanism for its removal was proposed based on DFT calculations and experimental results of electrochemistry and photocatalysis. This work offers a novel perspective on the rational design of integrated heterostructured materials with enhanced interfacial charge transfer for high-performance supercapacitors and visible light-driven photocatalysis.