title: Differential Electrochemical Mass Spectrometer Cell Design for Online Quantification of Products Produced during Electrochemical Reduction of CO₂.
abstract: The discovery of electrocatalysts that can efficiently reduce CO2 to fuels with high selectivity is a subject of contemporary interest. Currently, the available analytical methods for characterizing the products of CO2 reduction require tens of hours to obtain the dependence of product distribution on applied potential. As a consequence, there is a need to develop novel analytical approaches that can reduce this analysis time down to about an hour. We report here the design, construction, and operation of a novel differential electrochemical mass spectrometer (DEMS) cell geometry that enables the partial current densities of volatile electrochemical reaction products to be quantified in real time. The capabilities of the novel DEMS cell design are demonstrated by carrying out the electrochemical reduction of CO2 over polycrystalline copper. The reaction products are quantified in real time as a function of the applied potential during linear sweep voltammetry, enabling the product spectrum produced by a given electrocatalyst to be determined as a function of applied potential on a time scale of roughly 1 h.
authors.affiliation: †Joint Center for Artificial Photosynthesis, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.|‡Department of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720-1462, United States.
authors.forename: Ezra L
authors.initials: EL
authors.lastname: Clark
authors.affiliation: †Joint Center for Artificial Photosynthesis, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.
authors.forename: Meenesh R
authors.initials: MR
authors.lastname: Singh
authors.affiliation: †Joint Center for Artificial Photosynthesis, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.
authors.forename: Youngkook
authors.initials: Y
authors.lastname: Kwon
authors.affiliation: †Joint Center for Artificial Photosynthesis, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.|‡Department of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720-1462, United States.
authors.forename: Alexis T
authors.initials: AT
authors.lastname: Bell