Ambient CO2 capture and conversion into liquid fuel and fertilizer catalyzed by a PdAu nano-alloy

Abstract

CO2 capture and utilization (CCU) into high-value-added chemicals is an attractive strategy to mitigate global warming. However, the current CCU techniques commonly require harsh conditions, such as high temperature or pressure or complex purification, to achieve pure products. Here, we report a CCU route, which can capture and convert CO2 into liquid fuel (HCOOH) and fertilizer (NH4H2PO4) under ambient conditions. Specifically, a (NH4)2CO3 aqueous solution first captures CO2 as NH4HCO3, which is hydrogenated into HCOONH4 by a PdAu nano-alloy. The route can achieve ∼0.56 mmol/g CO2 capture capacity and ∼32.6% conversion under ambient conditions. Then, the solution is phosphorylated and distilled into HCOOH solution and NH4H2PO4 solid at 373 K. Catalyst characterizations reveal that the PdAu alloying effect and the nearby amine group on the catalyst enrich the adsorption of HCO3− and thus boost catalyst activity. This work offers a simple and useful strategy for conversion of CO2 into high-value-added chemicals.