Dilute Pd₃Co₉₅₀ alloy encapsulated in defect- and N-rich carbon nanotubes for universal highly efficient aqueous-phase catalysis

Integration of dilute alloy with Mott-Schottky heterojunction has been achieved in porous sea-urchin-like N-rich carbon (CN) encapsulated Pd3Co950 alloy. Simply prepared through ZIF-67@C3N4 pyrolysis and trace Pd doping, the Pd3Co950@CN catalyst possesses dispersed high-electron-density Pd with electrons transferring from base Co and outer CN. Thanks to the enhanced metal-N-x coordination and discrete active surface Pd on Co, it displays excellent turnover frequency of 1656 h(-1) for cinnamaldehyde hydrogenation of C=C group with similar to 100% selectivity, and remarkable substrate tolerance in catalyzing various environmentally benign reactions in water, including hydrogenation of N-heterocycles and oxidation of benzyl alcohol. An array of experimental and theoretical studies, including in-situ characterization, kinetic analysis, and DFT calculations verify that the extraordinary performance is mainly attributed to the bimetallic electronic synergy and strong coordination with CN support. This facile synthesis strategy incorporates bimetallic synergy, strong support coordination, and optimized microstructure, thus enabling universality of cost-effective multifunctional catalysts.