Honeycomb-like Ni3(NO3)2(OH)4@Ni/Co-BTC composites as electrode materials for high performance supercapacitors

Highlights: • Honeycomb-like Ni₃(NO₃)₂(OH)₄@Ni/Co-BTC is facilely synthesized in situ synthesis method. • Ni₃(NO₃)₂(OH)₄@Ni/Co-BTC electrodes have a high capacitance of 1959 F g⁻¹ at 1 A g⁻¹. • Ni₃(NO₃)₂(OH)₄@Ni/Co-BTC shows maximum energy density of 106.7 Wh kg⁻¹. • The Ni₃(NO₃)₂(OH)₄@Ni/Co-BTC is the promising material for energy storage applications. Featuring abundant pore structure, the metal–organic frameworks (MOFs) have invoked new feasibilities to the full potential of electrode materials in emerging supercapacitors. Here, a novel honeycomb-like Ni₃(NO₃)₂(OH)₄@Ni/Co-BTC is elaborately fabricated by growing Ni₃(NO₃)₂(OH)₄ on the surface of Ni/Co-MOF substrate by solvent thermal method. The Ni₃(NO₃)₂(OH)₄@Ni/Co-BTC-based supercapacitor with extremely high specific capacity (1959 F g⁻¹ at 1 A g⁻¹) is contributed to the unique honeycomb-like structure of electrode. The capacitance contribution analysis indicates that Ni₃(NO₃)₂(OH)₄@Ni/Co-BTC belongs to pseudocapacitive materials. The reported strategy is expected to provide new insight into electrode designing for high-capacity supercapacitors, thus broadening the application of MOFs in this field.