By combining ultrahigh vacuum (UHV) surface analysis with electrochemistry, ex situ studies offer a new, vastly detailed route for examining electrochemical phenomena. This approach is applied to the study of methanol and formic acid electrocatalysis on single crystal, metal electrodes. These reactions are important in fuel-cell applications, but the lack of mechanistic understanding, particularly of spontaneous poisoning, inhibits further development. This work applies concepts from gas-phase heterogeneous catalysis to build a paradigm for understanding electrocatalytic behavior. The mechanistic details of the reactions, individually and in the presence of modifiers, are studied with a combination of UHV and electrochemical cross-characterization experiments and post-electrochemical analyses in UHV. The growth modes and surface chemistry of metallic and nonmetallic modifiers are examined as well. The research directly address the important issues that stand in the way of development of direct methanol fuel cells. However, of perhaps equal importance to the advancement of this important (because of energy resource limitations and environmental considerations) technology is the development and refinement of the ex situ methodology for the study of electrochemical systems, which could have a major impact on industrial process work.
