Construction of nano-flower MIL-125(Mo)-In2Se3 Z-scheme heterojunctions by one-step solvothermal method for removal of tetracycline from wastewater in the synergy of adsorption and photocatalysis way

Abstract

• A novel nano-flower adsorbent photocatalyst was firstly prepared by one-step solvothermal method. • The nano-flower heterojunction between MIL-125(Mo) and In 2 Se 3 effectively promoted carrier separation and transfer. • The M-In-1 exhibited remarkable adsorption and photocatalytic activity towards tetracycline. The synergy of adsorption and photocatalysis has received considerable attention in the field of environmental remediation. In this work, a novel nano-flower MIL-125(Mo)-In 2 Se 3 (M-In) adsorbent photocatalyst was firstly prepared by one-step solvothermal method. Benefiting from the 3D nano-flower structure, tightness 2D/2D heterojunction interface, highly exposed active site of MIL-125(Mo) and the spontaneous polarization of lamellar In 2 Se 3 , M-In exhibited an excellent adsorption and photodegradation performance in removal of tetracycline (TC) pollutants . The results of adsorption kinetic and adsorption equilibrium were well fitted by Pseudo-second-order model and Freundlich isotherm model, indicating that the adsorption progress was non-uniform and multilayer. In addition, the degradation rate of TC reached 94.14% within 120 min under visible light exposure in the presence of optimum ratio M-In-1. The results of trapping experiments, three-dimensional excitation-emission matrix (3D-EEM) fluorescence spectroscopy and liquid chromatograph-mass spectrometer showed that h + played a significant role and O 2 – also played a role in the photo-degradation process. Hence, the novel adsorbent photocatalyst can be used to treat TC wastewater and the study gives some inspiration for the design and construction of efficient photocatalysts.