Thermodynamically controlled photo-electrochemical CO2 reduction at Cu/rGO/PVP/Nafion multi-layered dark cathode for selective production of formaldehyde and acetaldehyde

Transforming greenhouse gases such as CO2 to energy rich carbon-based chemicals is considered as one of the most efficient technologies for environmental and energy sustainability. However, CO2 is highly stable molecule and difficult to reduce due to its linear structure. The rate of reduction and the nature of fuel product depend on the kinetics and thermodynamics of involved reactions. While the overall reaction kinetics depends on the energy of activated CO2 molecule and its subsequent transition states along with reduction dynamics. Here we demonstrate that by activation of thermodynamically stable CO2 molecule through complexation or coordination with suitable activator such as N-heterocyclic polymers (e.g., poly(4-vinyl)pyridine, PVP), both the kinetics and thermodynamics of photoelectrochemical CO2 reduction reaction can be controlled by proper choice of electrode materials and bias potential. We present a solar light driven photoelectrochemical process for producing formaldehyde and acetaldehyde selectively on multi-layered Cu/rGO/PVP/Nafion hybrid cathode.

Automated summary

Transforming greenhouse gases like CO2 into energy rich carbon-based chemicals is efficient for environmental and energy sustainability. However, the stable and linear structure of CO2 makes it difficult to reduce. By activating CO2 through complexation with suitable activators, the kinetics and thermodynamics of the photoelectrochemical CO2 reduction reaction can be controlled, leading to selective production of formaldehyde and acetaldehyde in a solar light driven process.