“…Co p )/N-CNTs] was also prepared from ZnCo-ZIF and applied for HMF oxidation, and the synthesis process was shown in Figure 17. Outstanding catalytic performance was exhibited due to the preferable catalytic activities of Co single atoms (Co 1 ) and Co nanoparticles (Co p ), and the catalyst achieved 100 % HMF conversion efficiency and 96 % FDCA yield under 0.1 MPa O 2 atmosphere at 100 °C for 8 h. [101] Manganese oxides have been extensively investigated in broad fields, such as use as catalysts [99,102] or the supports of active metal, [94,95] owing to their low cost, Earth abundance, and specific chemical properties. It is generally acknowledged that manganese oxides have diverse crystal structures and a redox cycle between + 2 and + 4 oxidation states, providing outstanding redox reactions of Mn 2 + /Mn 3 + or Mn 3 + /Mn 4 + , and oxygen mobility within the oxide lattice.…”