Rational Regulation of Electronic Structure in Layered Double Hydroxide Via Vanadium Incorporation to Trigger Highly Selective CO Photoreduction to CH.

To realize excellent selectivity of CH in CO photoreduction (CO PR) is highly desirable, yet which is challenging due to the limited active sites for CH generation and severe electron-hole recombination on photocatalysts. Herein, based on the theoretically calculated effects of vanadium incorporation into the laminate of layered double hydroxides (LDHs), V into NiAl-LDH to synthesize a series of LDHs with various V contents is introduced. NiV-LDH is revealed to afford a high CH selectivity (78.9%), and extremely low H selectivity (only 0.4%) under λ > 400 nm irradiation. By further tuning the molar ratio of Ni to V, a CH selectivity of as high as 90.1% is achieved on Ni V-LDH, and H is completely prohibited on Ni V-LDH. Fine structural characterizations and comprehensive optical and electrochemical studies uncover V incorporation creates the lower-valence Ni species as active sites for generating CH , and enhances the generation, separation, and transfer of photogenerated carriers.