Substitutionally Dispersed High‐Oxidation CoOx Clusters in the Lattice of Rutile TiO2 Triggering Efficient CoTi Cooperative Catalytic Centers for Oxygen Evolution Reactions. (18th December 2020)

• Record Type: Journal Article
• Authors: Yan, Yong; Liu, Chunyue; Jian, Hanwen; Cheng, Xing; Hu, Ting; Wang, Dong; Shang, Lu; Chen, Ge; Schaaf, Peter; Wang, Xiayan; Kan, Erjun; Zhang, Tierui
• Is Part Of: Advanced functional materials. Volume 31:Number 9(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-12-18
• Subjects: cooperative catalytic centers -- CoOx clusters -- high oxidation state -- oxygen evolution reaction -- rutile TiO 2; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adfm.202009610
• Languages: English
• ISSNs: 1616-301X

Abstract

Abstract: The development of economical, highly active, and robust electrocatalysts for oxygen evolution reaction (OER) is one of the major obstacles for producing affordable water splitting systems and metal‐air batteries. Herein, it is reported that the subnanometric CoO x clusters with high oxidation state substitutionally dispersed in the lattice of rutile TiO2 support (Co‐TiO2 ) can be prepared by a thermally induced phase segregation process. Owing to the strong interaction of CoO x clusters and TiO2 support, Co‐TiO2 exhibits both excellent intrinsic activity and durability for OER. The turnover frequency of Co‐TiO2 is up to 3.250 s −1 at overpotentials of 350 mV; this value is one of the highest in terms of OER performance among the current Co‐based active materials under similar testing conditions; moreover, the OER current density loss is only 6.5% at a constant overpotential of 400 mV for 30 000 s, which is superior to the benchmark Co3 O4 and RuO2 catalysts. Mechanism analysis demonstrates that charge transfer occurs between Co sites and their neighboring Ti atoms, triggering the efficient CoTi cooperative catalytic centers, in which OH* and O* are preferred to be adsorbed on the bridging sites of Co and Ti with favorable adsorption energy, inducing a lower energy barrier for O2 generation. Abstract : High‐oxidation CoO x clusters substitutionally dispersed in the lattice of a rutile TiO2 support (Co‐TiO2 ) are obtained by a thermally induced phase segregation process and following O2 plasma treatment; the strong interaction between CoO x clusters and TiO2 support induce the formation of CoTi cooperative catalytic centers, which enable the substantially improved intrinsic activity and stability of Co‐TiO2 for oxygen evolution reaction.