To mitigate excess anthropogenic carbon dioxide emissions (~4 GtC yr⁻¹) and realise the Paris Agreement on the climate change agenda of 2⁰C target, circular carbon economy is considered an impactful technology which is getting cheaper with decreasing costs of renewable energies. Converting CO₂ into methanol which can be used as a fuel for methanol fuel cells or to upscale for different factory chemicals, currently derived from fossil fuels, can help in achieving net-zero or negative emissions^[1]. Electrochemical carbon dioxide reduction (ECO2R) is paired with an anodic half-reaction which is limited by high overpotentials and low stability^[2]. An efficient anodic valorisation process integrated with ECO2R is crucial for small cell voltage and long-lasting devices. Oxygen evolution reaction (OER) is the most common anodic half-reaction paired with ECO2R. In a membrane electrode assembly, anodic reaction releases electrons and protons that are used at the cathode to reduce CO₂ and higher O₂ generation rate modulates the ECO2R towards higher faradaic efficiency.

One of the constraints for OER is the stability of the electrocatalyst at high current densities, which corrodes to form an inactive surface layer which limits currents or leaches out into the alkaline/neutral solution. Here, we co-electrodeposited thin films of poly-metal oxides of Ni, Fe and Cu^[3] from a slightly acidic solution through pulsed currents on Tantalum foil. These poly-metal oxide-based films were analysed in 1M KOH and recorded an overpotential of 270 mV for a benchmark current of 10 mA/cm² and cell voltage of 1.83 V (RHE) at 100 mA/cm² current stable for 25 hours of the OER process.

To mitigate the corrosion of metal substrates with KOH, which can lead to decrease in OER activity, we have deposited a range of Cu, Fe, and Ni-based catalysts on highly conductive substrates such as Ni foam and porous carbon papers to enhance current density and stability simultaneously. We have also deposited Mxenes, polyvinylidene fluoride (PVDF) and other piezoelectric functional coatings on poly-metal oxides thin films to induce piezopotential through mechanical deformation of coatings by the anolyte flow. This extra potential is aligned in a direction to lower the overpotential and enhance the stability of CuFeNi electrocatalysts for both alkaline and near-neutral OER. We will also present our studies on the impact of the anodic environment on the selectivity and activity of copper-based catalysts for ECO2R to frame a roadmap for anodes in alkaline and polymer electrolyte membrane CO₂ electrolysers. Our study will pave the way toward the fabrication of next generation electrochemical system for sustainable direct CO₂ capture and utilization/storage as clean solar fuel.