In-situ construction of durable Cu+ species for the catalytic hydrodeoxygenation of biomass-derived aldehydes

The structural reconstruction of Cu-based catalysts during the hydrodeoxygenation (HDO) process typically leads to the loss of active Cu + species and catalyst sintering, resulting in catalyst deactivation. Herein, we found that Pr-doped CuO x catalyst undergoes in-situ reconstruction to generate stable Cu + species during the HDO of vanillin (VAN) to 2-methoxy-4-methylphenol (MMP). This affords a high MMP yield of 85.5% using methanol as both the solvent and hydrogen donor, which is significant higher than that of pristine CuO x and previously reported catalysts for the HDO of VAN in MeOH. Electronic interactions between Pr dopants and the CuO x matrix strengthen the Cu–O bonds and stabilize Cu + species, thereby increasing the density of acidic sites and oxygen vacancies in the catalyst. This not only promotes MeOH decomposition for H 2 generation, but also facilitates VAN adsorption and activation, thereby boosting HDO activity. This work offers new insights for the in-situ construction of highly active and durable Cu + sites in Cu-based catalysts.