AMPERE-2: an open-hardware, robotic platform for automated electrodeposition and electrochemical validation

Abstract

An Opentrons OT-2 liquid-handling robot was used as the framework to develop an automated platform for the electrodeposition and electrochemical testing of multi-element catalysts. Catalytic activity was demonstrated via alkaline water splitting, specifically targeting the oxygen evolution reaction (OER). The setup integrates multiple pumps, a flushing tool, custom deposition and electrochemical testing electrodes, and a potentiostat to enable reproducible and efficient electrodeposition and evaluation. Stock solutions of metal chlorides were combined with two complexing agents, ammonium hydroxide and sodium citrate, to stabilize the deposition process and tune the surface morphology. Analysis by cyclic voltammetry and electron microscopy revealed that the complexing agents significantly influenced deposition rates and surface structures, with the most effective catalysts forming either in the absence of additives or when both agents were applied together. Deposition times of 30–60 seconds yielded the lowest OER overpotentials, indicating an optimal catalyst layer thickness. The platform demonstrates robust reproducibility with uncertainty in overpotential measurements at 16 mV.