A novel AgCl-based visible-light photocatalyst through in-situ assembly of carbon dots for efficient dye degradation and hydrogen evolution

Abstract A novel efficient AgCl-based heterojunction photocatalyst was synthesized by in-situ electrostatic-assembly of carbon dots (CDs) for the first time. Distinct from the physical blending between CDs and AgCl (CDs + AgCl), CDsAg was heterojuncted into AgCl in this work. The resulting CDsAg-AgCl photocatalyst was endowed with significantly enhanced visible-light photocatalytic performances in both dye degradation and hydrogen evolution With a Cl−/Ag+ molar percentage of 90% and visible light irradiation, methyl orange (MO) was degraded within 30 min with a degradation efficiency of 0.069 min−1, which was about 42.3, 8.9 and 10.6 times higher than those of CDs, AgCl and CDsAg+AgCl, respectively. It also yielded an excellent hydrogen evolution efficiency of 617.4 μmolg−1 h−1, exhibiting a high potential in the field of energy regeneration. Moreover, it showed a good reusability and stability after 5 recycles for both degradation and hydrogen evolution. In addition, a possible photocatalytic mechanism was proposed, where CDsAg-AgCl heterojunction structure facilitated the transfer-separation of photo-generated electron-hole pairs to promote the photocatalytic performance. This work could provide a new route to prepare novel high-efficient photocatalysts for the energy and environmental application.