Kinetics Study of Silver Electrocrystallization on (3-mercaptopropyl)trimethoxysilane-grafted Indium Tin Oxide Plastic Substrate

• The larger charge transfer coefficient supports that MPS promotes electrodeposition.
• ACV shows that electron-transfer rate enhanced by 2.5 times after MPS treatment.
• The fitting of CA defined the Ag nucleation mode on blank and MPS-grafted ITO-PEN.
• MPS treatment changed the nucleation mode from 2-step to a single step one.

3-mercaptopropyl-trimethoxysilane (MPS) self-assembled monolayer (SAM) has been demonstrated as effective promoters to enable direct electroplated metallization on indium tin oxide (ITO) plastic substrate. In this paper, the detail kinetics in Ag electrocrystallization on MPS-grafted ITO-PEN is reported. Contact angle measurement provides evidence of bridging-link effect between the sulfur head groups of MPS and the Ag+ ions in the electrolyte. Electrochemical techniques including cyclic voltammetry and Tafel plot were used to investigate the redox kinetics. Quantitative evaluation was conducted by alternating current voltammetry to determine the rate constant of electron transfer. The chronoamperograms and their fitting results suggest a combined model with two-dimensional/three-dimensional nucleation transition and Shariker-Hills model for electroplated Ag on blank ITO-PEN and MPS-grafted ITO-PEN respectively.