Interfacial Affinity Determined Photocatalytic Activity: A Comparison between Defective and Bulk Polymeric Carbon Nitride

The photoexcited charge separation efficiency of photocatalysts is generally considered as the key factor for enhancement of their photocatalytic activity, and sometimes, their photoabsorption capability and interfacial reaction kinetics play a key part, but the role of interfacial affinity of photocatalysts with substrates was rarely researched systematically. Herein, nitrogen vacancy-modified polymeric carbon nitride porous nanotubes (PCNpts) were simply synthesized, using tartaric acid as a crosslinking and corrosion agent, and exhibit a remarkable increment in surface area, wettability, photoabsorption and charge separation capability, and photocatalytic activity in water splitting to produce H2, but, interestingly, exhibit substrate-dependent variation of photoactivity in contaminant degradation, compared with bulk PCN. More interestingly, the interfacial affinity of PCNpts and PCN with contaminants and H2O, rather than photoabsorption and charge separation capability, is confirmed to dominate their photoactivity.