Symmetry Breaking Induced Amorphization of Cobalt-based Catalyst for Boosted CO 2 Photoreduction.

Photocatalytic reduction of CO 2 to energy carriers is intriguing in industry but kinetically hard to fulfil due to the lack of rationally designed catalysts. A promising way to improve efficiency and selectivity of such reduction is to break structural symmetry of catalysts by manipulating coordination. Here, inspired by analogous CoO 6 and CoSe 6 octahedral structural motifs of the Co(OH) 2 and CoSe, we propose a hetero-anionic coordination strategy to construct a symmetry-breaking photocatalyst prototype of oxygen-deficient Se-doped cobalt hydroxide upon first-principles calculations. Such involvement of large-size Se atoms in CoO 6 octahedral frameworks experimentally lead to switching of semiconductor type of cobalt hydroxide from p to n, generation of oxygen defects, and amorphization. The resultant oxygen-deficient Se,O-coordinated Co-based amorphous nanosheets exhibit impressive photocatalytic performance of CO 2 to CO with a generation rate of 60.7 μmol g -1 h -1 in the absence of photosensitizer and scavenger, superior to most of the Co-based photocatalysts. This work establishes a correlation between symmetry-breaking of catalytic sites and CO 2 photoreduction performances, opening up a new paradigm in design of amorphous photocatalysts for CO 2 reduction. This article is protected by copyright. All rights reserved.