Establishing Compositional Control in 2D and 3D Metal Sulfide Electrocatalysts to Drive CO2 and CO Conversion to Alcohols (Hybrid)

Friday, February 25, 2022 - 1:10pm
Event Type: 


Dr. Jesus Velazquez

Dr. Jesus Velazquez, University of California Davis 

Host: Dr. Kovnir 

Abstract: Development of materials that address the growing dichotomy of simultaneously increasing energy demands and carbon emissions is an imperative that has progressively affected energy-related research efforts. An emerging technical avenue in this area is the conversion of vastly abundant renewable energy sources that can be harnessed and directed towards synthesis of traditionally fossil fuel-based products from atmospheric feedstocks like CO2. To this end, our work establishes structure—function relationships for materials within the versatile classes of MX2 (M = Mo, W; X = S, Se) and Chevrel-Phase (CP) MyMo6X8 (M = alkali, alkaline, transition or post-transition metal; y = 0-4; X = S, Se, Te) chalcogenides. The molybdenum sulfide structures from both families exhibit exceptional promise as CO2R catalysts. Furthermore, we have identified the CP catalyst framework as being selective towards the electrochemical reduction of CO2 and CO to methanol (only major liquid-phase product) under applied potentials as mild as -0.4 V vs RHE. Reactivity toward electrochemical reduction of CO2 and CO to methanol is correlated with increased population of chalcogen states, as confirmed via X-Ray Absorption Spectroscopy. Overall, this work seeks to unravel optimally reactive novel small-molecule reduction catalyst compositions.

Bio: Jesús M. Velázquez is an Assistant Professor in the Department of Chemistry at UC Davis. He leads a research program centered on the rational design of well-defined solid-state materials at the meso and nanoscale. The target materials have immediate applications in energy conversion devices and environmental remediation. Characterization of the physicochemical properties of these materials involves a combination of microscopy, spectroscopy, electrochemistry, and synchrotron-based methods and will facilitate the development of structure—function correlations that will iteratively inform solid-state materials design. He received his B.S. in Chemistry from the University of Puerto Rico at Cayey. His doctoral degree in Chemistry was at SUNY Buffalo and he then transitioned to a Postdoctoral appointment in the Division of Chemistry and Chemical Engineering at Caltech. Recent recognitions for his research program at UCDavis include an NSF CAREER Award, Cottrell Scholar Award, C&EN Talented 12, APS Stanford R. Ovshinsky Sustainable Energy Fellowship Award two separate Scialog Fellowships, and the University of California CAMPOS Scholar distinction.

Velazquez’s research and education efforts have been featured in journal special issues such as the Journal of Materials Chemistry Emerging Investigator, I&EC Research’s 2021 Class of Influential Researchers Issue, Journal of Chemical Education-Diversity, Equity, Inclusion, and Respect in Chemistry Education Research and Practice as well as Chemistry of Materials “Up and Coming” early career scientist.