LAUSR

Abstract Interfacial engineering provides efficient methods to enhance conductivity and structural stability of active electrode materials. Herein, 1–3 atomic layered Ti3C2 MXene is introduced to strengthen flexible Ni2Co-LDHs nanoarrays, forming the 3D irregular honeycomb-like sandwich-type composite. Strong interfacial interactions and excellent conductivity of AL-Ti3C2 MXene give the composite ultrahigh rate capability and long-life stability in battery-type supercapacitors. The rate capability reaches 126 mAh g−1 ​at 150 ​A ​g−1, ~5.7 times of pure Ni2Co-LDHs (22 mAh g−1), which can be up to 92 mAh g−1 even at 300 ​A ​g−1. It also gives outstanding stability of ~90% capacity retention after 10000 cycles (vs. ~17% for Ni2Co-LDHs). The introduced Ti3C2 MXene atomic layers much enhances the intrinsic performance of NiCo-LDHs. Density functional theory (DFT) calculation reveals 1.07 electrons transfer per unit cell from LDHs to AL-Ti3C2 MXene at the very stable interfaces with ultralow energy of −13.48 ​eV. The interfaces much improve conductivity and reaction kinetics of outer LDHs. The fabricated interfaces also decrease surficial hydrogen adsorption energy from 1.67 to 1.47 ​eV, benefiting for electrochemical performance. This work provides a feasible route to develop excellent battery-type electrode materials of supercapacitor via interfacial design.