Au nanoparticles modified HNTs/g-C3N4/CdS composite for highly efficient CO2 photoreduction and tetracycline degradation

In this research, Au nanoparticles (NPs) modified HNTs/g-C3N4/CdS composite (HCAC-3) photocatalyst was prepared for highly-efficient photocatalytic reaction. SEM and TEM results confirmed that the g-C3N4 was uniformly wrapped on the surface of HNTs, and Au and CdS NPs were also loaded on the surface of the HNTs/g-C3N4 composite. Photo-electrochemistry tests and density functional theory calculation results showed that the introducing Au NPs speeds up the photo-electric conversion and separation ratio of photogenerated carriers inside the catalyst. Additionally, the CO2 photoreduction experiments showed that the yields of CO and CH4 with HCAC-3 catalyst after 4 h irradiation with UV-Vis light were about 55.4 and 8.6 mu mol/g, respectively, which were about five times the performance of HNTs/g-C3N4 composite and the HCAC-3 has great photocatalytic stability. Besides, the photodegradation experiment of tetracycline aqu-eous solution showed that the HCAC-3 composite has excellent photodegradation activity. After 120 min, the tetracycline photodegradation ratio of HCAC-3 was about 87.4%, which is about 2.2 times higher than that of HNTs/g-C3N4 composite. Finally, the synergistic effect of g-C3N4/CdS type II heterojunction and the LSPR effect of Au NPs were investigated and determined as the main reasons for the improvement of the photocatalytic performance of the g-C3N4-based catalyst.(c) 2022 Elsevier B.V. All rights reserved.

Automated summary

In this research, Au nanoparticles modified HNTs/g-C3N4/CdS composite photocatalyst was prepared for highly-efficient photocatalytic reaction. The results showed that the introducing Au nanoparticles can accelerate the photo-electric conversion and separation, greatly improving the performance of the catalyst. Additionally, the HCAC-3 composite catalyst exhibited excellent photodegradation activity and photocatalytic stability.