Controlled pyrolysis of Zn-based metal organic framework-derived ZnO/C for Rhodamine-B degradation

Abstract

We study the structure and morphology of ZnO/C derived from a Zn-based metal-organic framework (Zn-MOF) prospected as a catalyst of Rhodamine-B degradation. ZnO/C was synthesized by one-step pyrolysis of Zn-MOF at 4500 C under various gasses of N2, O2, and air signed as ZnO/C-N2, ZnO/C˗O2, and ZnO/C˗air, respectively. Controlled environment pyrolysis has transformed the rod-like of Zn-MOF to become granular of ZnO/C˗O2 and spherical of ZnO/C˗air. We found that the ZnO/C˗air sample effectively reduced carbon atoms. Diffraction peaks of ZnO/C˗O2 exhibit higher crystallinity than ZnO/C˗air and ZnO/C-N2 for the dominant peak grown on (101) direction. Removing organic of Zn-MOF by pyrolysis treatment will produce the BET-specific surface area from 16.8 to 6.81, 12.15, and 29.26 m2/g of ZnO/C˗N2, ZnO/C˗O2, and ZnO/C˗air, respectively. ZnO/C˗air shows an excellent stability performance with efficiency up to 94.1% for degradation of Rhodamine-B. This study potentially provides a stable photocatalyst for waste-water purification, especially for Rhodamine-B degradation.