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Updated: Jun 12, 2026

A Rapid Synthesis Method for Au, Pd, and Pt Aerogels Via Direct Solution-Based Reduction
Published on: June 18, 2018
Electrocapillary maximum and potential of zero charge of carbon aerogel
Li-Hua Shao1, Jürgen Biener, Dominik Kramer
1Institute of Nanotechnology, Karlsruhe Institute of Technology, Karlsruhe, Germany. Lihua.Shao@kit.edu
Abstract:
We present an electrochemical study of carbon aerogel (CA) in aqueous sodium fluoride solutions, focusing on the comparison of two quantities that are related to the potential of zero charge (pzc): the capacitance minimum and the 'electrocapillary maximum' of the surface forces. Capacitance minima are well resolved in our samples. Their potential emerges reproducibly as around 90 mV (vs. Ag/AgCl in KCl), similar to the value, 70 mV, of bulk glassy carbon which we use for comparison, and similar to previous reported pzc values for carbon materials. Significantly, no electrocapillary maximum is found in this potential range. This demonstrates that the pzc does not necessarily coincide with the potential of the maximum of surface stress. We also determined the area-specific capacitances, c(a) = 2.8 microF cm(-2), which agrees well with reports for the basal-plane of graphite single crystals. Our experiments yield large reversible strain amplitudes, up to 0.45%.
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