Fig. 5: Calculated adsorption energy and structures of HMF.

(side view, Inset: top view). a, b Nb₂O₅ surface, which marked with blue background. c–f Pt₁/Nb₂O₅-Ov surface, which marked with green background. The adsorption modes for C=O (upper row) and the C–OH (bottom row) in HMF. Silver: C, white: H, red: O, light blue: Nb, blue: Pt.