Estimating surface area of copper powder: A comparison between electrochemical, microscopy and laser diffraction methods

Abstract

For heterogeneous catalytic/electrocatalytic reaction systems, estimation of the surface area of the catalyst is of great importance. As far as systems involving copper as catalyst are concerned, the literature reveals lack of a robust method to determine the surface area. In this work, we compare the surface area determined from electrochemical measurements, optical and electron microscopy and from laser diffraction experiments. Specifically, cyclic voltammetry in two different solutions involving two separate surface reactions has been used to measure the surface area. First involves the formation of a monolayer of Cu2O and the second involves formation of a monolayer of Pb. Additionally, the surface area was also estimated from the double layer capacitance of the copper electrode. The surface areas determined from these electrochemical measurements are in good agreement with those obtained from microscopy and particle size analyzers (for average copper particle diameter = 10 µm).