Catalytic Performance and Near-Surface X-ray Characterization of Titanium Hydride Electrodes for the Electrochemical Nitrate Reduction Reaction

Matthew J Liu; Jinyu Guo; Adam S Hoffman; Joakim Halldin Stenlid; Michael T Tang; Elizabeth R Corson; Kevin H Stone; Frank Abild-Pedersen; Simon R Bare; William A Tarpeh

doi:10.1021/jacs.2c01274

Catalytic Performance and Near-Surface X-ray Characterization of Titanium Hydride Electrodes for the Electrochemical Nitrate Reduction Reaction

J Am Chem Soc. 2022 Apr 6;144(13):5739-5744. doi: 10.1021/jacs.2c01274. Epub 2022 Mar 22.

Authors

Matthew J Liu¹, Jinyu Guo¹, Adam S Hoffman², Joakim Halldin Stenlid^{1

3}, Michael T Tang^{1

3}, Elizabeth R Corson¹, Kevin H Stone², Frank Abild-Pedersen³, Simon R Bare^{2

3}, William A Tarpeh^{1

3}

Affiliations

¹ Department of Chemical Engineering, Stanford University, Stanford, California 94305, United States.
² Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States.
³ SUNCAT Center for Interface Science and Catalysis, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States.

PMID: 35315649
DOI: 10.1021/jacs.2c01274

Abstract

The electrochemical nitrate reduction reaction (NO₃RR) on titanium introduces significant surface reconstruction and forms titanium hydride (TiH_x, 0 < x ≤ 2). With ex situ grazing-incidence X-ray diffraction (GIXRD) and X-ray absorption spectroscopy (XAS), we demonstrated near-surface TiH₂ enrichment with increasing NO₃RR applied potential and duration. This quantitative relationship facilitated electrochemical treatment of Ti to form TiH₂/Ti electrodes for use in NO₃RR, thereby decoupling hydride formation from NO₃RR performance. A wide range of NO₃RR activity and selectivity on TiH₂/Ti electrodes between -0.4 and -1.0 V_RHE was observed and analyzed with density functional theory (DFT) calculations on TiH₂(111). This work underscores the importance of relating NO₃RR performance with near-surface electrode structure to advance catalyst design and operation.

Publication types

Research Support, U.S. Gov't, Non-P.H.S.
Research Support, Non-U.S. Gov't

MeSH terms

Electrodes
Nitrates* / chemistry
Oxidation-Reduction
Titanium* / chemistry
X-Rays

Substances

Nitrates
Titanium