Effect of ultrasound irradiation on deposition of Au nanoparticles on carbon-coated cathode material

Abstract

The cathode material LiNi0.5Mn1.5O4 (LMNO) has attracted attention as a component of lithium-ion batteries for electro vehicles because it has a high discharge voltage of 4.7 V versus Li/Li+ via the redox potential of Ni4+/2+. However, the low electronic conductivity of the LMNO relates to a low discharge capacity at high current densities. A conductive carbon coating is known to improve this cathode material's electronic conductivity. In this study, we performed Au nanoparticles (NPs) deposition onto the carbon-coated LMNO (LMNO/C) using ultrasound irradiation. The carbon layer of LMNO/C produces an Au(III) ion that efficiently accepts electrons released from radicals generated by ultrasound irradiation. As a result, the size and morphology of the Au NPs, deposited onto the LMNO/C, were different when compared with the Au NPs deposited onto the LMNO. The Au NPs deposition onto the cathode material using ultrasound improved LMNO's electronic conductivity and increased the discharge capacity.