Photocatalysts made of earth-abundant elements are highly desired for photocatalytic H-2 evolution as well as bacterial inactivation without requirement of noble metal (i.e. Pt, Ag). In this study, nickel phosphide (Ni2P) was used as a nonprecious co-catalyst to couple with metal-free g-C3N4 based on Z-scheme type of electron transportation model. The exfoliation of bulk g-C3N4, the in-situ synthesis and anchoring of Ni2P nanoparticles onto the g-C3N4 nanosheets were achieved in one-step by a hydrothermal method without adding any surfactants or templates. The optimized Ni2P/g-C3N4 lamellar nanohydrids exhibited remarkably enhanced visible-light-driven photocatalytic activity for H-2 evolution and bacterial inactivation without noble metal loading, and the obtained activity is approximately 22 and 10 times higher than that of pure g-C3N4, respectively. The Ni2P was proposed to effectively trap the photo-generated e(-) via a Z-scheme type of route, thus significantly promoting the e(-)-h(+) separation and subsequent reduction of protons to generate H-2. The bacterial inactivation was found to undergo a direct h(+) oxidation process, and therefore the trapping of e- by Ni2P also facilitated h(+) accumulation, leading to enhanced bacterial inactivation efficiency. This study demonstrates a proof-of-concept for constructing all-earth-abundant photocatalysts without any noble metal elements for both energy production and environmental application. (C) 2017 Elsevier B.V. All rights reserved.