摘要
This work describes the use of TiO_(2)nanotubes-based electrodes(TNT)modified with Cu_(2)O nanostructures and gold nanoparticles for the photoelectroreduction of CO_(2)to produce value-added compounds.A thin layer of polydopamine was used as both an adherent agent and an electron transfer mediator,due to itsπ-conjugated electron system.The highest production yield was achieved using a TNT@PDA/Nc/Au40%electrode,with Faradaic efficiencies of 47.4%(110.5μM cm^(-2))and 27.8%(50.4μM cm^(-2))for methanol and methane,respectively.The performance of the photoelectrodes was shown to be Cu_(2)O facet-dependent,with cubic structures leading to greater conversion of CO_(2)to methanol(43%)and methane(27%),compared to the octahedral morphology,while a higher percentage of metallic gold on the nanostructured Cu_(2)O surface was mainly important for CH4production.Density functional theory(DFT)calculations supported these findings,attributing the superior photoelectrocatalytic performance of the TNT@PDA/Nc/Au40%electrode for CH4generation to the formation of an OCH3intermediate bonded to Au atoms.Studies using isotope-labeling and analysis by gas chromatograph-mass(GC-MS)demonstrated that13CO_(2)was the source for photoelectrocatalytic generation of13CH3OH and13CH313CH2OH.
基金
FAPESP,Brazil(#2023/10027-5,#2014/50945-4,#2020/15230-5,and#2021/000675-4)
CNPq,Brazil(#465571/2014-0,#303269/2021-9,and#307837/2014-9)
Instituto Serrapilheira(grant number Serra-2211-41925)
FAPEMIG,Brazil(#PPM-00831-15)for support of this work
CNPq,Brazil(#105944/2022-0)and PROPEUNESP(13/2022)
FAPESP(#2019/00463-7,#2018/22845-6,and#2021/08007-0,respectively)for scholarships
the National Institute for Alternative Technologies of Detection,Toxicological Evaluation and Removal of Micropollutants and Radioactives(INCT-DATREM)
the support of the Research Centre for Greenhouse Gas Innovation(RCGI),hosted by the University of Sao Paulo(USP)and sponsored by FAPESP and Shell Brasil
the strategic support given by ANP,Brazil(Brazilian National Oil,Natural Gas,and Biofuels Agency)through the R&D levy regulation。