Oxygen evolution reaction (OER) is an essential reaction and often a limiting step in many electrochemical devices that hold great potential for clean energy conversion and fuel transformation. The two paramount questions remain unclear in OER heterogeneous catalyst design: (1) how to identify and construct well-defined catalytic centers for efficient OER catalysis, and (2) how to delineate unambiguously the atomistic mechanism and kinetics for OER and competitive reactions at this center. In this work, we developed a new synthesis for the single-site cobalt (Co) doped TiO<sub>2</sub> nanorods with well-defined catalytic surface (210). This material was systematically studied with a suite of operando probes under electrochemical conditions and exhibited a record-high intrinsic activity for the OER reported to date. Moreover, based on grand canonical quantum mechanics (GCQM) calculations on well-defined single-site Co atomic structure, we establish a full description of reaction kinetics for the Co-TiO2 as a function of applied potential, revealing an adsorbate evolution mechanism for the OER. The computationally predicted Tafel slope and TOFs also exhibit unprecedently good agreement with experiment. Thus, we demonstrated a methodological advance for the study of OER by combining the atomic-precision synthesis of nanocrystals and GCQM calculations. With the accuracy of GCQM calculations validated here, it can potentially allow us to perform high-accuracy in-silico design of rational catalyst and subsequently maximize its benefit through controlled synthesis of nanocatalysts.

Oxygen evolution reaction over catalytic single-site Co in well-defined brookite TiO<sub>2</sub> nanorod surface

ACS Spring Meeting 2021

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Oxygen evolution reaction over catalytic single-site Co in well-defined brookite TiO2 nanorod surface

Oxygen evolution reaction over catalytic single-site Co in well-defined brookite TiO₂ nanorod surface