|About this Abstract
||2021 TMS Annual Meeting & Exhibition
||Metal-Matrix Composites: Advances in Analysis, Measurement and Observations
||Kinetics and Thermodynamics of Metal Cluster Nucleation over Graphene Oxide
||Abhay Gupta, Chandan Srivastava
|On-Site Speaker (Planned)
Electrochemical nucleation and growth of Sn and Co over graphene oxide (GO) was studied using the chronoamperometry (CA) technique. Metal reduction over GO was carried out from aqueous sulfate solutions under constant voltage condition. Mathematical modelling of CA results revealed that diffusion-controlled nucleation of Sn and Co was preceded by the formation of double-layer of adsorbed atoms over the GO substrate. A simultaneous proton reduction reaction was also observed over the growing metal nuclei. The rate of nucleation and proton reduction increased with increase in the overpotential. Under the experimental conditions, the free energy of formation of critical nucleus was comparable to the room temperature thermal energy, which indicated that nucleation was a kinetically controlled process. Application of Milchev’s atomistic theory of nucleation suggested that at high overpotentials, every atom of Sn and Co that got deposited over GO, can act as a supercritical nucleus that can grow irreversibly.
||Copper / Nickel / Cobalt, Thin Films and Interfaces, Composites