Apparatus for testing gas-surface reactions for epicatalysis.

Rev Sci Instrum

Department of Physics, University of San Diego, 5998 Alcala Park, San Diego, California 92110, USA.

Published: July 2016

Recently, a new mode of gas-surface heterogeneous catalysis (epicatalysis) has been identified, having potential applications ranging from industrial and green chemistry to novel forms of power generation. This article describes an inexpensive, easily constructed, vacuum-compatible apparatus by which multiple candidate gas-surface combinations can be rapidly screened for epicatalytic activity. In exploratory experiments, candidate surfaces (teflon, kapton, glass, and gold) and gases (helium, argon, cyclohexane, water, methanol, formic acid, and acetic acid) were tested for epicatalytic activity. Kapton and teflon displayed small but reproducible differences in formic acid and methanol dimer desorption, thereby demonstrating the first examples of room-temperature epicatalysis. Other gas-surface combinations showed smaller or inconclusive evidence for epicatalysis.

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http://dx.doi.org/10.1063/1.4954971DOI Listing

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