In order to explore a new electrocatalyst (or its precursor) for oxygen evolution reaction (OER), much attention has recently been given to the alternative engineering strategy for fabricating a novel nanofilm electrode with high efficiency and long duration. We herein use a two-step electrodeposition method to prepare a series of nanofilm electrodes containing Ni, Co, P, and Se on carbon cloth. After a suitable electrochemical activation process through cyclic voltammetry, the resultant binder-free NiCoP−NiCoSe 2 nano-bilayer films are transformed from compact layer(s) to porous nanoparticle ones composed by NiCo hydroxides and a small amount of NiCo oxyhydroxides and thus exhibit a striking electrocatalytic activity (lower to 243 mV overpotential for 10 mA cm −2 ) and excellent stability (80 h) for OER. The rougher surface, well-suited electronic structure originated from the Ni/Co codoping and the rational integration of NiCoP and NiCoSe 2 are important factors for the excellent OER performance of the NiCoP−NiCoSe 2 film after the electrochemical activation process. In addition, the results on overall water splitting reveal that the NiCoP−NiCoSe 2 film is also promising in the practical application of energy conversion and storage.

Titanium nitride (TiN) decorated N-doped titania (N-TiO 2 ) composite (TiN/N-TiO 2 ) is fabricated via an in situ nitridation using a hydrothermally synthesized TiO 2 and melamine (MA) as raw materials. After the optimization of the reaction condition, the resultant TiN/N-TiO 2 composite delivers a hydrogen evolution activity of up to 703 μmol/h under the full spectrum irradiation of Xelamp, which is approximately 2.6 and 32.0 times more than that of TiO 2 and TiN alone, respectively. To explore the underlying photocatalytic mechanism, the crystal phase, morphology, light absorption, energy band structure, element composition, and electrochemical behavior of the composite material are characterized and analyzed. The results indicate that the superior activity is mainly caused by the in situ formation of plasmonic TiN and N-TiO 2 with intimate interface contact, which not only extends the spectral response range, but also accelerates the transfer and separation of the photoexcited hot charge carrier of TiN. The present study provides a fascinating approach to in situ forming nonmetallic plasmonic material/N-doped TiO 2 composite photocatalysts for high-efficiency water splitting.Keywords photocatalytic H 2 evolution, TiN/N-TiO 2 composite, plasmonic effect, in-situ nitridation *