Catalytically Stable Potassium Single-Atom Solid Superbases.

Angew Chem Int Ed Engl

State Key Laboratory of Materials-Oriented Chemical Engineering, Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), College of Chemical Engineering, Nanjing Tech University, Nanjing, 211816, China.

Published: December 2022

AI Article Synopsis

  • Solid superbases provide effective catalysis under mild conditions, but face issues with aggregation and stability during recycling.
  • A new type of solid superbase, created from potassium single atoms (SAs) using a two-step redox process, has been developed to overcome these challenges.
  • The K/G hybrid demonstrates superior catalytic performance and stability in transesterification reactions, attributed to its unique superbasicity and the high dispersion of basic sites.

Article Abstract

Solid superbases can catalyze diverse reactions under mild conditions, while they suffer from aggregation of basic sites and poor stability during recycling. Here we report a new generation of solid superbases derived from K single atoms (SAs) prepared by a tandem redox strategy. The initial redox reaction takes place between base precursor KNO and graphene support, producing K O at 400 °C. Further increasing the temperature to 800 °C, the graphene reduces K O to K anchored by its vacancies, leading to the generation of K SAs (denoted as K /G). The source of basicity in the K /G is K SAs, and neighboring single atoms (NSAs) possess superbasicity, which is different from conventional basicity originated from oxygen and nitrogen atoms. Due to the superbasicity as well as high dispersion and anchoring of basic sites, the K /G shows excellent catalytic activity and stability in transesterification reaction, which is much superior to the reported catalysts.

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http://dx.doi.org/10.1002/anie.202215157DOI Listing

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