2024 AIChE Annual Meeting
(569fq) Pyroelectric Driven Energy Force in Cobalt Phthalocyanine/ Graphene Catalyst Pair for Simultaneous Dual CO2 Reduction and H2 evolution Reactions
As the urgency of climate change grows, the need for efficient, eco-friendly energy sources like hydrogen (H2) intensifies. Meanwhile, global carbon emissions exacerbate the greenhouse effect and global warming. Despite growing interest in CO2 reduction reactions (CO2RR) and H2 production, challenges persist, including selectivity and high costs associated with electrochemical approaches, as well as low efficiency in photocatalytic methods. In this regard, the utilization of a huge available heat-waste energy source would be highly beneficial and could potentially be achieved using pyroelectric materials, certain structures that, surprisingly, can convert even a modest periodic temperature fluctuation into electrical energy. Here, we confronted this challenge by synergistically exploiting the pyroelectric and electrocatalytic properties of planar molecules (e.g. cobalt phthalocyanine (CoPc)). By demonstrating such a pyroelectric property of CoPc, we present an unprecedented opportunity for CO2RR and water splitting (as a dual reaction) without the need for external electrical power, relying solely on thermal cycling. Our pyrocatalyst exhibits high CO productivity in the CO2RR, with yield as high as 15 and H2 evolution 25 within 12 few-second thermal cycles between 5–50 °C. This fantastic feature comes from an electric field induced due to the separation of charges within the pyrocatalyst with thermal cycling, resulting in a combination of asymmetry in CoPc cell volume expansion coupled with the reorientation and rotation of the CoPc molecule.

