Shan Liu,Zhiquan Yu,Yao Wang,Zhichao Sun,Yingya Liu,Chuan Shi,Anjie Wang
Catalytic dehydration of glycerol over solid catalysts provides a sustainable and economic route to producing acrolein. Unsupported MoP catalyst was prepared by temperature-programmed-reduction method and used for the gas-phase glycerol dehydration. The catalyst was characterized by means of XRD, SEM, TEM, NH 3 -TPD, Py-IR, XPS, TG-DSC, and N 2 adsorption-desorption. It is indicated that the acidic P OH and M oOH groups, which are usually associated with the weak or moderate strength of Brønsted acid sites, were presented on the surface of MoP. The effects of reaction temperature and carrier gas flow rate on glycerol conversion and acrolein selectivity were investigated over MoP. The selectivity to acrolein was up to 89.0 % and kept constant in a 50-h run at 240 °C. The gradual decrease of glycerol conversion might be related to the insoluble carbonaceous materials deposited on the catalyst surface.
Profiting from Pt-like electronic structure and high electrical conductivity, molybdenum phosphide (MoP) has received widespread attention as a hydrogen evolution reaction (HER) catalyst. Although various effective strategies have been developed to regulate the bare MoP synthesis, the electrocatalytic performance of MoP is still far from satisfactory, especially in pH-universal applications. Recently, doping of heterogeneous elements, particularly for rare earth (RE) metals, has been emerged as an effective method to precisely regulate the local electronic structure of phosphides. Herein, the novel and controllable La/Yb-doped MoP nanoparticles encapsulated in nitrogen-doped carbon matrix (MoP@NC) are synthesized. The as-prepared La/Yb-doped catalysts (RE-MoP@NC (RE = La, Yb)) exhibit fantastic HER electrocatalytic performance for both activity and durability in a wide pH range. Detailed structural characterizations and density functional theory (DFT) calculations validate that the electronic densities around Mo and P atoms are effectively tuned by La/Yb doping atoms, resulting in the optimization in Gibbs free energy of MoP toward the hydrogen adsorption, which can boost its intrinsic HER activity. This research enriches RE-modified catalysts and reveals that the RE metal doping can be extended to other non-noble metal catalysts as a general method.
危险品化学品经营许可证（带存储）