Black Phosphorus as Promoter for Noble Metal‐Free Photocatalytic Hydrogen Production

Abstract

Abstract Photocatalysts which are stable to photocorrosion and noble metal‐free, are highly desirable to achieve a light‐driven hydrogen production which satisfies the criteria of low production cost and environmental sustainability. Herein, a new heterostructure TiO 2 /BP/CoP has been developed, in which the BP nanosheets interact strongly with TiO 2 and CoP, speeding up the transfer of photogenerated electrons and thus increasing H 2 production. Once BP is added to TiO 2 (P25) as only 1 % wt., the H 2 evolution rate increases up to 4 times reaching a value of 830 μmol/g ⋅ h under UV‐Vis light irradiation. By integrating CoP nanoparticles as a cocatalyst up to 2 % wt., H 2 production is further promoted to 7400 μmol/g ⋅ h, 37 times higher than pristine TiO 2 . Photoluminescence and electrochemical impedance measurements show that this heterostructure achieves a much more efficient charge separation and reduction of the internal resistance in comparison to pristine TiO 2 . Combining these data with UV‐Vis diffuse reflectance and Mott‐Schottky, a plausible mechanism was proposed.