木质素模板法制备纳米花状炭负载Ag-ZnO及其光催化CO2转化OA北大核心CSTPCD

Using lignin(AL)as a template,nanoscale lignin-loaded zinc oxide(ZnO/AL)composite materials were prepared.Silver nanoparticles(AgNPs)were loaded onto this base material,and a nano-flower-shaped carbon loaded silver-zinc oxide(Ag-ZnO/C)composite material was prepared through high-temperature calcination.The composite materials were characterized using scanning electron microscopy(SEM),transmission electron microscopy(TEM),X-ray diffraction(XRD),and X-ray photoelectron spectroscopy(XPS),and their ability for photocatalytic conversion of CO2 was evaluated.The research results showed that when using lignin as a template,ZnO/AL could maintain the nano-flower morphology and structure during the subsequent calcination processes,and lignin could reduce silver ions in situ to AgNPs,uniformly loading them on the ZnO petal layers.Energy-dispersive X-ray spectroscopy(EDX)results showed that Ag-ZnO/C composite material was mainly composed of C(14.7%),O(14.4%),Zn(34.1%)and Ag(18.0%)elements.Combined with TEM,XRD,and XPS analysis,the successful preparation of the Ag-ZnO/C composite material was confirmed.The ability of photocatalytic CO2 conversion of the composite materials with different Ag+/Zn2+ ratios of 1∶2(Ag0.1-ZnO0.2/C)and 1∶10(Ag0.1-ZnO1.0/C)was compared.Photocurrent response and impedance spectroscopy test results indicated that Ag0.1-ZnO1.0/C had higher photocurrent intensity,lower resistance,and superior photocatalytic activity.The photocatalytic CO2 conversion by Ag0.1-ZnO1.0/C showed consistently low CH4 production,and the CO yield could reach 114.9 μmol/g after 10 hours of reaction.