Dissolved oxygen in aeration-driven piezo-catalytic for antibiotics pollutants removal in water

The misuse of antibiotics and oxygen-lacking in aquaculture causes serious water environmental problems.Herein,a piezoelectic odd-layered MoS_(2)is prepared and applied to piezo-catalytic remove tinidazole(TNZ)and other antibiotic pollutants with aeration as a piezo-driving force.About 89.6%of TNZ can be degraded by MoS_(2)under aeration in the presence of dissolved oxygen with a reaction rate constant of0.15 min^(-1),which is 2.4 times higher than that under N2atmosphere and quiescence conditions.Quenching experiments and electron paramagnetic resonance(EPR)tests identify that singlet oxygen(^(1)O_(2))and superoxide radical(O_(2)^(·-))are dominant reactive oxygen species in MoS_(2)/aeration system.These results demonstrate that MoS2can trigger a piezoelectric effect and produce charge carriers to generate reactive oxygen species with dissolved oxygen(DO)for contaminant degradation with the turbulence and water bubbles rupture driven by aeration.

Efficient ozone decomposition over bifunctional Co_(3)Mn-layered double hydroxide with strong electronic interaction

Ground-level ozone is one of the primary pollutants detrimental to human health and ecosystems.Catalytic ozone decomposition still suffers from low efficiency and unsatisfactory stability.In this work,we report a manganese-based layered double hydroxide catalyst(Co_(3)Mn-LDH),which exhibited a superior ozone decomposition performance with the efficiency of 100% and stability over 7 h under a GHSV of 2,000,000 mL g^(-1)h^(-1) and relative humidity of 15%.Even when the relative humidity increased to 50%,the ozone decomposition also reached 86%,which significantly exceeds as-synthesized MnO_(2) and commercial MnO_(2) in performance.The catalytic mechanism was studied by H_(2)-TPR,FT-IR and XPS.The excellent performance of Co_(3)Mn-LDH can be attributed to its abundant surface hydroxyl groups that ensured the preferentially surface enrichment of ozone,as well as the cyclic dynamic replenishment of electrons between multivalent Co^(2+)/Co^(3+),Mn^(2+)/Mn^(3+)/Mn^(4+)and oxygen species that endowed the stable ozone decomposition.This work offers new insights into the design of efficient catalysts for ozone pollution control.

Visible light-assisted peroxydisulfate activation via hollow copper tungstate spheres for removal of antibiotic sulfamethoxazole

The contamination of antibiotics in aqueous environment causes increasing concerns recently.Lightassisted activation of peroxydisulfate(PDS)has been demonstrated as an efficient technology for re moval of contamination in water.Herein,a hollow sphere of CuWO_(4)(h-CuWO_(4))was employed as a visible lightactivated photocatalyst for the activation of PDS,and following with high removal efficiency(98%)of antibiotic sulfamethoxazole(SMX).Under visible light irradiation,the degradation rate on hollow structures system is nearly 2 times higher than the traditional solid CuWO_(4) spheres.Furthermore,the underlying mechanism and detailed pathway of SMX degradation were proposed based on density functional theory(DFT)calculations and liquid chromatography-mass spectrometry(LC-MS).This work provides a new feasible way for advanced oxidation processes to remove antibiotics SMX in heterogeneous system,and open up new application possibilities of CuWO_(4)-based materials.