Construction of Ag/AgCl-CN heterojunctions with enhanced photocatalytic activities for degrading contaminants in wastewater.

The non-metallic organic polymer carbon nitride has attracted widespread attentions, but its photocatalytic performance is unsatisfactory due to high recombination of photoinduced carriers. To solve this issue, we report Ag/AgCl-decorated carbon nitride (CN) nanorod heterojunctions as efficient and stable photocatalyst. CN nanorods (diameter: ∼25 nm; lengths: 1-1.5 μm) were prepared by a simple solvothermal route, and then in-situ growth of Ag/AgCl nanoparticles (diameter: 20-40 nm) on CN surface was realized by a facile co-precipitation method. Ag/AgCl-decorated CN heterojunctions with diverse Ag/CN precursor molar-ratios (0.3, 0.5, 0.7) exhibit a wide absorption spectrum from UV to visible-light region (∼750 nm). After the illumination of visible-light for 120 min, 0.5-Ag/AgCl-CN nanorods can degrade 98.5% rhodamine B (RhB), 75.4% tetracycline (TC) and 39.5% Cr(VI), obviously better than those of CN nanorods (62.6% RhB, 35.6% TC, 19.7% Cr(VI)), Ag/AgCl nanoparticles (66.5% RhB, 18.5% TC, 24.6% Cr(VI)) and Ag-CN (72.6% RhB, 39.4% TC, 28.7% Cr(VI)). This obvious improvement should result from efficient separation of photogenerated carriers. Therefore, Ag/AgCl-CN can act as an efficient and stable visible-light-driven photocatalyst.