Chinese Journal of Applied Chemistry ›› 2023, Vol. 40 ›› Issue (4): 597-609.DOI: 10.19894/j.issn.1000-0518.220321

• Energy Materials • Previous Articles     Next Articles

Ionic Liquid-Modulated Synthesis of Pt-Pd Bimetallic Nanomaterials and Their Catalytic Performance for Ammonia Borane Hydrolysis to Generate Hydrogen

Hui-Hui LI, Kai-Sheng YAO(), Ya-Nan ZHAO, Li-Na FAN, Yu-Lin TIAN, Wei-Wei LU()   

  1. Chemical Engineering & Pharmaceutics School,Henan University of Science & Technology,Luoyang 471023,China
  • Received:2022-10-07 Accepted:2023-02-22 Published:2023-04-01 Online:2023-04-17
  • Contact: Kai-Sheng YAO,Wei-Wei LU
  • About author:luwei1980@126.com
    ksyao@haust.edu.cn
  • Supported by:
    the National Natural Science Foundation of China(21673067);the Key Science and Technology Project of Henan Province(192102210043)

Abstract:

Herein, under the modulation of an ionic liquid 1-tetradecyl-3-methylimidazole bromide ([C14mim]Br), Pt-Pd bimetallic nanomaterials are prepared in one-pot at 90 ℃ in aqueous solution with polyvinylpyrrolidone (PVP) as the stabilizer. The morphology, structure, components and valence states of the products are characterized and analyzed in detail by transmission electron microscopy (TEM), scanning electron microscopy (SEM), high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffractometry (XRD) and X-ray photoelectron spectrometer (XPS). The results show that except for pure Pd sample, Pt-Pd bimetallic nanomaterials with other Pt/Pd ratios have porous structures. [C14mim]Br plays an important role in regulating the synthesis of Pt-Pd porous nanomaterials. For the ionic liquids [C n mim]Br with the alkyl chain length≥C12, it is beneficial for the formation of porous Pd@Pt spherical structures. In the experiment of the ammonia borane hydrolysis, Pt-Pd bimetallic nanomaterials with various ratios show higher catalytic activities than commercial Pd/C, among which Pt3Pd7 nanomaterials have the best catalytic performance. The hydrogen generation reaction can be quickly achieved within only 6 min and the hydrogen yield is up to 100%. At 25 ℃, the activation energy (Ea) and the turnover frequency (TOF) values are calculated to be 36.15 kJ/mol and 35.72 mol/(mol·min), respectively. Furthermore, the reaction for the five catalytic cycles can be achieved within 51 min, and the yield can still reach 100%, indicating that the catalyst has high activity and good stability.

Key words: Ionic liquids, Pt-Pd bimetals, Nanomaterials, Hydrogen production of ammonia borane hydrolysis

CLC Number: