A novel three-dimensional (3D) nano-crystal platinum (Pt) was introduced as a high-performance layer on the Pt substrate to provide extremely large surface, which significantly reduced electrical impedance by ~93% and increased the cathodic charge storage capacity (CSCc) up to ~100 mC·cm^-2 (27 times) compared with that of bare Pt electrodes. In addition, the 3D nano-crystal Pt coating exhibited great mechanical and electrochemical stability as well as biocompatibility, which was critical and beneficial for effective neural stimulation/recording electrodes for practical applications.