In this study, Co2P semiconductors are obtained from in situ phosphorylation of CoV-LDH, functioning as the main active center in photocatalysts for efficient photocatalytic hydrogen evolution. Co2P semiconductors are proven to accelerate the rate of hydrogen evolution by enriching the active sites of the catalyst. Addnl., numerous neg.-charged P atoms can trap active protons, thus improving the kinetics of hydrogen evolution. To directionally control the carrier migration, a highly efficient and stable surface-phosphorized CoV-LDH/Co2P cocatalyst is further synthesized by modifying CoV-LDH with different phosphorylation ratios. As a result, the optimized P-CoV-LDH photocatalyst had a hydrogen evolution activity of 434.5 μmol, which is 32.57 times that of the single catalyst CoV-LDH, 60.77 times that of P-V-LDH, and 1.4 times that of P-Co-LDH, resp. This work paves the way to precisely design noble-metal-free cocatalysts through selective phosphorylation.