Highly dispersed Pd icosahedra and Ag nanocubes on ultrathin g-C3N4 nanosheet for boosting photocatalytic bacterial inactivation and organic pollutants degradation

Engineering surface facet of metallic nanoparticles that decorated on certain substants is an intriguing strategy to modulate photocatalytic capacity. Herein, a novel photocatalyst by doping g-C3N4 3 N 4 nanosheet with Pd icosahedra with {11 1} facets and Ag nanocubes with {100} facets were firstly synthesized through facile wet-chemical route. The successfully constructed g-C3N4/Pd/Ag 3 N 4 /Pd/Ag composites were employed as a visible-light-driven dual- functional photocatalyst for bacterial inactivation and organic contaminant degradation. Result suggested that 1 x 108 8 CFU/mL E. coli strains can be totally inactivated by g-C3N4/Pd/Ag 3 N 4 /Pd/Ag within 60 min, outperformed that of {1 00} faceted enclosed Pd nanocubes functioned g-C3N4/Ag. 3 N 4 /Ag. Also, the optimized g-C3N4/Pd/Ag 3 N 4 /Pd/Ag exhibited ideal photocatalytic performance toward tetracycline and methylene blue degradation. The rate constant was found to be 8.74 x 10-3-3 and 7.08 x 10-3-3 min-- 1 , respectively, which was higher than those of bare g-C3N4 3 N 4 and g-C3N4/Pd. 3 N 4 /Pd. Quenching experiment and electron paramagnetic resonance analysis suggested that hole (h+), + ), electron (e-- ), and superoxide radical (center dot O2- center dot O 2- ) exerted a key role in the improved capacity. Furthermore, the more positive Fermi level of Pd icosahedra and Ag nanocubes relative to that of g-C3N4 3 N 4 also contributed to the enhanced photocatalytic performance. Collectively, our work can provide in-depth insight into fabricate novel facet-engineering photo- catalyst for environmental applications.