title: Reduced SnO2Porous Nanowires with a High Density of Grain Boundaries as Catalysts for Efficient Electrochemical CO2-into-HCOOH Conversion.
abstract: Electrochemical conversion of CO2into energy-dense liquids, such as formic acid, is desirable as a hydrogen carrier and a chemical feedstock. SnOxis one of the few catalysts that reduce CO2into formic acid with high selectivity but at high overpotential and low current density. We show that an electrochemically reduced SnO2porous nanowire catalyst (Sn-pNWs) with a high density of grain boundaries (GBs) exhibits an energy conversion efficiency of CO2-into-HCOOH higher than analogous catalysts. HCOOH formation begins at lower overpotential (350 mV) and reaches a steady Faradaic efficiency of ca. 80 % at only -0.8 V vs. RHE. A comparison with commercial SnO2nanoparticles confirms that the improved CO2reduction performance of Sn-pNWs is due to the density of GBs within the porous structure, which introduce new catalytically active sites. Produced with a scalable plasma synthesis technology, the catalysts have potential for application in the CO2conversion industry.
authors.affiliation: Conn Center for Renewable Energy Research, University of Louisville, Louisville, KY, 40292, USA.
authors.forename: Bijandra
authors.initials: B
authors.lastname: Kumar
authors.affiliation: Conn Center for Renewable Energy Research, University of Louisville, Louisville, KY, 40292, USA.
authors.forename: Veerendra
authors.initials: V
authors.lastname: Atla
authors.affiliation: Conn Center for Renewable Energy Research, University of Louisville, Louisville, KY, 40292, USA.
authors.forename: J Patrick
authors.initials: JP
authors.lastname: Brian
authors.affiliation: Conn Center for Renewable Energy Research, University of Louisville, Louisville, KY, 40292, USA.
authors.forename: Sudesh
authors.initials: S
authors.lastname: Kumari
authors.affiliation: Conn Center for Renewable Energy Research, University of Louisville, Louisville, KY, 40292, USA.
authors.forename: Tu Quang
authors.initials: TQ
authors.lastname: Nguyen
authors.affiliation: Conn Center for Renewable Energy Research, University of Louisville, Louisville, KY, 40292, USA.
authors.forename: Mahendra
authors.initials: M
authors.lastname: Sunkara
authors.affiliation: Conn Center for Renewable Energy Research, University of Louisville, Louisville, KY, 40292, USA.
authors.forename: Joshua M
authors.initials: JM
authors.lastname: Spurgeon
keywords: CO2 reduction; grain boundaries; heterogeneous catalysts; porous nanowires; tin oxide