(389ad) Density Functional Theory Studies of Biomass Electrooxidation on Doped Tin Oxide Supported Platinum Single Atom Catalysts

Biomass upgrading to commercially relevant chemicals can help increase the sustainability of the chemical industry. Furfural is a promising biomass-derived species that can be partially oxidized to furanones and furoic acid. These chemicals are used in applications like surface coatings, food adhesives, and pharmaceuticals¹. However, selectivity challenges arise in direct oxidation processes due to carboxylate poisoning on metal catalysts. Electro-oxidation of furfural can serve as a potential alternative to help avoid carboxylate poisoning². Single atom catalysts (SACs) supported on conductive dopants in oxides are a class of electrocatalyst that can be used for electrochemical biomass oxidation. There are minimal studies of the use of (doped) oxide supported SACs as electrocatalysts, leaving open questions as to their structure, stability, and mechanistic role in promoting oxidation electrocatalysis.

Experimental work within our collaborative project includes synthesis and catalytic testing of Pt SACs supported on both pure and antimony doped tin oxide, and their evaluation for CO and furfural oxidation. This poster will report density functional theory (DFT) computational results examining the surface structure and binding of reaction intermediates. Varying degrees of oxide and SAC surface oxidation and hydroxylation are considered as a function of applied potential. The impact of oxide doping on the stable structure and oxidation extent of the SAC is examined. Important descriptors of furfural oxidation activity, including CO and OH binding, are determined, again as a function of SAC structure and support oxide doping. DFT results suggest incorporating Sb doping results in weaker CO binding, promoting CO oxidation on the Pt SAC at lower overpotentials. Collectively, the role of conductive dopants in metal oxide supported SACs is probed for electro-oxidation catalysis.

References

• Collinson, S.R.; Thielemans, W.; The catalytic oxidation of biomass to new materials focusing on starch, cellulose and lignin, Coordination Chemistry Reviews, Volume 254, Issues 15–16, 2010, Pages 1854-1870, DOI: 10.1016/j.ccr.2010.04.007
• Gong, Li.; Agrawal, N.; Roman , A. et al. Density functional theory study of furfural electrochemical oxidation on the Pt (1 1 1) surface, Journal of Catalysis, Volume 373, 2019, Pages 322-335, DOI: 10.1016/j.jcat.2019.04.012