Synergistic poly(lactic acid) photoreforming and H₂ generation over ternary Ni_xCo_1-xP/reduced graphene oxide/g-C₃N₄...

Effective utilization of photoexcited electrons and holes is always a challenge in photocatalytic reactions. Herein, we reported ternary Ni_xCo_1-xP/reduced graphene oxide/g-C₃N₄ (Ni_xCo_1-xP/rGO/CN) composite as a photocatalyst for synergistic poly(lactic acid) photoreforming and H₂ generation in alkaline aqueous solution. The rate of H₂ production over the optimal 15Ni_0·1Co_0·9P/rGO/CN reached 576.7 μmol h^-1 g^-1, which is 3.6 times as high as binary 15Ni_0·1Co_0·9P/CN composite. The apparent quantum efficiency of the optimal 15Ni_0·1Co_0·9P/rGO/CN was 1.7% at λ = 420 nm monochromatic light. Mott-Schottky analysis suggested that the photogenerated electrons transfer along the pathway of CN→rGO→Ni_0·1Co_0·9P, where rGO and Ni_0·1Co_0·9P functioned as the medium for electron transporting and reaction site for H₂ generation, respectively. Meanwhile, poly(lactic acid) was photoreformed into formate and acetate by the photogenerated holes and hydroxyl radical. This work demonstrates that ternary Ni_xCo_1-xP/rGO/CN composite can be applied as a cheap and promising photocatalyst for synergistic plastic photoreforming and H₂ generation.