Growth of nickel (111) plane: The key role in nickel for further improving the electrochemical property of hexagonal nickel hydroxide-nickel & reduced graphene oxide composite

Hexagonal nickel hydroxide/nickel decorated on reduced graphene oxide (rGO&Ni(OH)2–Ni) has been prepared via easy one-step chemical precipitation method and subsequent annealing treatment. The results show that the thermal stability of Ni(OH)2 is enhanced by the incorporation of Ni. Besides, hexagonal Ni(OH)2–Ni nanoplate which can supply a short diffusion and migration pathway for electron and electrolyte ion contacts closely with the surface of rGO, resulting that the agglomeration of rGO is effectively prevented. Due to the good electrical conductivity of Ni, the incorporation of Ni can also improve the electrical conductivity of Ni(OH)2. More importantly, the Ni (111) plane is grown after annealing treatment, which plays a key role in Ni for further improving the electrochemical activity of composite. Consequently, the rGO&Ni(OH)2–Ni electrode exhibits high capacitance, high energy density, excellent rate capability, good cycle stability, etc. The advantages of easy preparation and excellent electrochemical performance imply the great potential application of rGO&Ni(OH)2–Ni in supercapacitors. Moreover, it is worthy noting that this work will offer a new approach for using metal nanoparticle in improving the electrochemical property of supercapacitor electrode material. Hexagonal Ni(OH)2–Ni&reduced graphene oxide composite is prepared via easy one-step chemical precipitation method and subsequent annealing treatment. The existence of Ni enhances thermal stability of Ni(OH)2 and improves electrochemical performance of composite. Moreover, Ni (111) plane is grown after annealing treatment, which plays a key role in Ni for further improving electrochemical activity. Consequently, the composite exhibits excellent electrochemical property. [Display omitted] •A reduced graphene oxide and Ni(OH)2/Ni (rGO&Ni(OH)2–Ni) composite is got easily.•The existence of Ni can enhance the thermal stability of Ni(OH)2.•The coexistence of rGO and Ni can greatly improve the electrical conductivity.•The (111) plane plays a key role in Ni for improving the electrochemical activity.•The rGO&Ni(OH)2–Ni composite exhibits superior electrochemical property.