Black TiO2 (H-TiO2), as a promising photoanode material, can be used for direct green hydrogen production without emissions to pollute the environment, but the reported surface engineering approaches for the preparation of black TiO2 suffer from high temperatures, long processing time, or chemical residues, limiting its practical application in green hydrogen production. Here, we developed two advanced surface engineering technologies, overcoming the above limitations, to prepare a black TiO2 photoanode that achieved the maximum photocurrent density reported to date. Moreover, we theoretically and experimentally revealed the formation mechanism of black TiO2 and its enhanced photoelectrochemical (PEC) performance. These surface engineering technologies are not only suitable for the preparation of efficient photoanode materials for PEC hydrogen production but also play a beneficial and promoting role in the research and development of new materials for hydrogen fuel cells and hydrogen storage.