Graphene nanoplatelets: A promising corrosion inhibitor and toughening inclusion in plasma sprayed cerium oxide coating

Present article communicates the successful fabrication of plasma sprayed graphene nanoplatelets (GNPs) reinforced ceria (CeO2) composite coating. Later, various characterizations confirm the presence of survived GNPs into CeO2 matrix and its transformation to few layered graphene during plasma spraying. The reinforcement of GNPs led a significant enhancement in corrosion resistance and mechanical performance. Addition of 5 wt% GNPs in CeO2 displayed an exceptional reduction in corrosion rate about similar to 15 times in 3.5 wt% NaCl solution, while superior improvement of 50% in hardness, 98% in elastic modulus and 185% in fracture toughness during indentation has been observed. The GNPs acted as promising corrosion inhibitor and prevented infiltration of electrolytic salts (NaCl) through the coating. Apart from these, entanglement of few layer GNPs with CeO2 matrix and GNP crack bridging between two crack banks enhanced the mechanical performance of the matrix. As a whole, GNPs reinforcement owed the combined improvement in corrosion resistance as well as mechanical performance, which would make it a better option for advanced technological applications. (C) 2019 Elsevier B.V. All rights reserved.