Surface engineering of biochar toward simultaneously generating superamphiphilicity and catalytic activity for strengthening Pickering interfacial catalysis

Multifunctional carbon materials have revealed distinctive features and excellent performance in the field of catalysis. However, the facile fabrication of bifunctional carbon materials with special wettability and catalytic activity remains a grand challenge in Pickering emulsion catalysis. Herein, we reported one-step construction of bifunctional biochar with superamphiphilicity and catalytic activity directly from the thermolysis of sawdust and 1-butyl-3-methylimidazolium tetrafluoroborate for enhancing the oxidation of benzyl alcohol in Pickering emulsion. Co-doping of B and F enhanced the hydrophilicity of biochar, and the oleophilicity of biochar was kept simultaneously. Conversion became 4 times using bifunctional biochar compared with blank results during the oxidation of benzyl alcohol. More interestingly, the turnover frequency (TOF) value using bifunctional biochar enhanced 61 % than that employing N-doped superamphiphilic carbon without catalytic activity. Catalytic activities of bifunctional biochar could be ascribed to the existence of different chemical bonds containing the element B. This work paves a path toward rational design of bifunctional biochar materials with special wettability and catalytic activity for greatly enhancing the liquid-liquid biphasic reaction efficiencies.