The fabrication and attractive performance of Ni(OH)(2)/Ni immobilized on TiO2 nanotube arrays (TNAs) as binder -free electrode was described. The resulting Ni(OH)(2)/Ni/TNAs brings better capabilities to electrochemical devices by combining the advantages of TNAs and Ni(OH)(2)/Ni composites. The prominent electrocatalytic activity toward formaldehyde permits effective low applied potential (0.35 V) amperometric sensing and exhibits fast response time (1 s). Furthermore, the composite electrode has high electrocatalytic rate constant of 5.36 x 10(5) cm(3) mol(-1) s(-1) for formaldehyde oxidation. Meanwhile, XPS analysis results offer insights to the nature of the Ni(OH)(2)/Ni/TNAs surface. What's more, the electrocatalytic mechanism for the oxidation of formaldehyde on Ni(OH)(2)/Ni/TNAs electrode was also clarified. The in -situ synthesized Ni(OH)(2)/Ni/TNAs electrode providing a remarkable catalytic activity is the novelty in this study.