Oxygen vacancy-rich MoOx enables selective C-C bond cleavage for boosted glyceric acid production from xylose

The oxidation of inexpensive sugars into high value glyceric acid holds considerable appeal, yet faces a fundamental challenge in achieving precise cleavage of the target C–C bond, resulting in inefficient catalysis. Herein, a MoO x -N 2 catalyst rich in oxygen vacancies (Ov) was successfully constructed via a self-assembly and two-stage annealing process. The developed catalyst efficiently converted xylose into glyceric acid under alkali-free conditions, achieving an excellent yield of 54.3% (0.905 mol/mol). Catalyst characterizations and density functional theory (DFT) calculations confirmed that Ov promote charge transfer between MoO x -N 2 and H 2 O/O 2 , accelerating the generation of active ·OH and 1 O 2 species, thereby enhancing the xylose oxidation efficiency. Furthermore, Ov induced an upshift in the d-band center of electron-rich Mo, favoring the adsorption and activation of xylose and glyceraldehyde intermediate, significantly lowing the energy barriers for cascade ring-opening, C–C bond cleavage and oxidation reactions. DFT calculations further revealed that Ov benefited the removal of proton in C3–OH of xylose, subsequently facilitating selective C2–C3 bond cleavage and ultimately achieving high yield of glyceric acid. This work highlights the pivotal role of Ov in enhancing the catalytic efficiency of xylose oxidative conversion, providing an efficient strategy for glyceric acid production. Oxygen vacancy-rich MoO x catalyst enables efficient, alkali-free conversion of xylose to glyceric acid via enhanced reactive oxygen species generation and reactants adsorption/activation, selective C2–C3 bond cleavage and reduced energy barriers. • Ov-rich MoO x -N 2 achieved excellent glyceric acid yield of 54.3% (90.5 mol%) from xylose under base-free conditions • Ov promoted the generation of active ·OH and 1 O 2 species • Ov facilitated the adsorption and activation of xylose and glyceraldehyde intermediate • Ov benefited the removal of proton in C3–OH and facilitated selective C2–C3 bond cleavage • Ov-rich MoO x -N 2 reduced the energy barriers for cascade ring-opening, C–C bond cleavage and oxidation