Single Atomic Cu-N2 Catalytic Sites for Highly Active and Selective Hydroxylation of Benzene to Phenol.

ABSTRACT: Searching for an efficient single-atom catalyst for benzene hydroxylation to phenol is of critical importance, but it still remains a challenge. Herein, a single-atom catalyst with unique Cu-N2 moieties (Cu1-N2/HCNS) was prepared and confirmed by HAADF-STEM and EXAFS. Turnover number (TON) over Cu1-N2/HCNS (6,935) is 3.4 times of Cu1-N3/HCNS (2,034) under the same reaction conditions, and both exhibit much higher phenol selectivity (close to 99%) and stability compared with Cu nanoparticles and nanoclusters. Experiments and DFT calculations reveal that atomically dispersed Cu species are active sites for benzene hydroxylation to phenol, and the Cu-N2 is more active than Cu-N3 owing to its much lower energy barrier concerning the activation of H2O2 led by its unique coordination state of local atomic structure. We envision that this work opens a new window for modulating coordination environments of single metallic atoms in catalysis design.

SUBMITTER: Zhang T 

PROVIDER: S-EPMC6880104 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature