Plating Methodologies of Nickel Catalysts for Chemical Vapor Deposition of Carbon Electrode Materials Applied in Supercapacitors

Abstract

This study establishes a new benchmark by achieving the most economical and efficient manufacturing process currently feasible, pushing the boundaries of affordability and scalability in supercapacitor electrode fabrication. This systematic study focuses on optimizing Ni-plating processes, including both electroless and electroplating methods, for the deposition of Ni catalysts to enable the fabrication of carbon nanomaterial-based supercapacitor electrodes via the chemical vapor deposition process. A notable strength of this work is the use of commercially available plating solutions to deposit Ni catalysts on pre-etched Al foil, emphasizing simplicity and cost-effectiveness. Ni plating is identified as the most economical and scalable method, making it a promising approach for transitioning supercapacitor fabrication to industrial production. In the electroless plating process, deposition time and temperature were varied between 1–180 minutes and 40–90°C, respectively. For the electroplating process, current density and time were controlled within the ranges of 2–36 mA/cm² and 1–30 minutes, respectively. Carbon nanomaterials were synthesized using an atmospheric pressure chemical vapor deposition (APCVD) process with optimized ratios of argon, hydrogen, and acetylene gases at 500°C.

The results demonstrated that for electroless plating, optimal Ni deposition occurred at 90°C for 15 minutes, producing samples with strong adhesion and high carbon mass loading after CVD growth. Similarly, for electroplating, a current density of 32 mA/cm² applied for 5 minutes resulted in the best adhesion and carbon mass loading. The highest areal capacitance was achieved with the 90°C-15-minute electroless-plated sample, measuring 1358.94 mF/cm², while the electroplated sample prepared at 32 mA/cm² for 5 minutes exhibited a capacitance of 1273.52 mF/cm². Both samples displayed low equivalent series resistance (ESR) values of 3.44 Ω and 1.09 Ω, respectively. These findings underscore the potential of optimized Ni-plating processes to enhance the performance of carbon nanomaterial-based supercapacitor electrodes, paving the way for cost-effective and industrial-scale energy storage device fabrication.