From brew to clean fuel: harnessing distillery wastewater for electrolysis H2 generation using nano scale nickle selenide water oxidation catalysts

This study reports a promising and innovative approach for electrochemical green H2 generation using distillery industry wastewater. We employed solvothermally derived Ni2Se3 nanoparticles with a particle size of ∼50 nm as the anode catalyst material to effectively oxidise the acetic acid present in the distillery wastewater. The utilisation of a Ni2Se3 nanoparticle-coated stainless steel electrode significantly enhanced the current density (282 mA cm−2) in the electrochemical cell compared to the pristine SS (stainless steel) electrode (146 mA cm−2) at 2 V RHE. Also, the distillery wastewater electrolyte based cell exhibits higher current density compared to conventional freshwater (i.e., NaOH-based) electrolyte. The distillery wastewater electrolyte demonstrated remarkable H2 gas evolution (∼15 mL h−1 cm−2), showcasing its potential for sustainable H2 generation. However, it was observed that the aggressive bubbling effect at the cathode led to a lower H2 evolution reaction activity when compared to the freshwater-based electrolyte, which displayed a H2 production rate of ∼22 mL h−1 cm−2. These findings underscore the potential of employing Ni2Se3 as an effective oxidation catalyst in the production of H2 gas from pre-treated brewery wastewater H2 gas. The utilisation of Ni2Se3 nanoscale water oxidation catalysts in this context opens up new possibilities for both wastewater treatment and H2 production, paving the way for a more sustainable and resource-efficient future.