Electrochemical mass spectrometry
By interfacing an electrochemical cell with a mass spectrometer via a pervaporation membrane, dissolved volatile products can be detected and identified by mass fragments almost instantaneously during electrocatalyst testing. This enables, for example, the determination of potential-dependent product formation across the whole potential range during a single linear sweep voltammetry experiment.
Reference: Clark, E. L., et al. Differential Electrochemical Mass Spectrometer Cell Design for Online Quantification of Products Produced during Electrochemical Reduction of CO2. Anal. Chem. 2015, 87 (15), 8013–8020.
Gas outflow from the cell is separated and quantified by gas chromatography (GC), enabling precise quantification for Faradaic efficiency determinations. Products measured include carbon monoxide, hydrogen, oxygen, methane, ethylene, and other gaseous hydrocarbons.
A separate autosampler channel allows automated sampling of liquid vials for volatile liquids determination (alcohols, aldehydes).