Optical second harmonic generation as a probe of hydrogen evolution on copper

In situ video STM studies of the hydrogen-induced reconstruction of Cu(100): potential and pH dependence

“…1 The only relevant experimental work is an in situ second harmonic generation study of the HER on polycrystalline Cu in neutral electrolyte solutions, which found a continuous increase in signal over a wide range of overpotentials and concluded from this a corresponding gradual change in y H . 26 However, whether these results are truly at variance with our assessment of a y H saturation on Cu(100) at rather low overpotentials is difficult to judge: Apart from the different sample structure and pH, the assignment of the non-linear optic response to the H coverage is not unambiguously, since it can be influenced by a variety of interface phenomena (including surface reconstructions).…”

Enabling Electrocatalytic Fischer–Tropsch Synthesis from Carbon Dioxide Over Copper-based Electrodes

“…6. Firstly, Hewitt reported that the surface coverage of adsorbed hydrogen increases as a function of increasing negative potential [20]. Second, it has been reported that the CO surface coverage, which is proposed to be a key intermediate in CO 2 reduction, is also a function of the applied potential [21].…”

A review of the aqueous electrochemical reduction of CO2 to hydrocarbons at copper

“…It was also determined that both steps are irreversible and the steady state coverage of adsorbed hydrogen is small. Another study using optical second harmonic generation and closer to neutral solutions (pH 5.5-6.5) determined the reaction follows steps 19 and 20, with 19 being rate determining [62].…”