Description
The electrochemical conversion of urea rich wastewater into value added products presents a promising strategy for sustainable water treatment, energy generation, and resource recovery for long duration space missions. In this work, boron-doped diamond (BDD) electrodes sequentially modified with nickel and platinum nanoparticles were developed to investigate enhanced urea oxidation and selective ammonia production in the presence of Proteus mirabilis. Nickel was first electrodeposited onto the BDD surface to provide high catalytic activity toward urea oxidation, followed by platinum surface modification to improve electron transfer kinetics, catalytic stability, and ammonia selectivity. The bioelectrochemical system leverages the urease activity of Proteus mirabilis to hydrolyze urea while the Pt–Ni catalytic interface promotes subsequent electrooxidation of ammonia to nitrogen. Electrochemical characterization using cyclic voltammetry showed improved electrochemical surface activity compared to unmodified electrodes. The integrated Pt–Ni–BDD microbial platform demonstrates potential for simultaneous wastewater remediation, ammonia generation, and water recovery, with prospective applications in sustainable environmental treatment systems and closed-loop resource utilization for long-duration space missions.