Hu Xiaoyu, Wang Jinchuan, Li Shangkun, Hu Xuanhao, Ye Rongxing, Zhou Linsen, Li Peilong, Chen Changlun
Institute of Plasma Physics, HFIPS, Chinese Academy of Sciences Hefei 230031 PR China
University of Science and Technology of China Hefei 230026 PR China.
RSC Adv. 2023 May 16;13(22):14980-14990. doi: 10.1039/d3ra01788e. eCollection 2023 May 15.
Extensive research has been devoted to developing metal nanoparticle (NP) doped porous materials with large hydrogen storage capacity and high hydrogen release pressure at ambient temperature. The ultra-sound assisted double-solvent approach (DSA) was applied for sample synthesis. In this study, tiny Pd NPs are confined into the pore space of HKUST-1, affording Pd@HKUST-1-DS with minimizing the aggregation of Pd NPs and subsequently the formation of Pd NPs on the external surface of HKUST-1. The experimental data reveal that the obtained Pd NP doped Pd@HKUST-1-DS possessed an outstanding hydrogen storage capacity of 3.68 wt% (and 1.63 wt%) at 77 K and 0.2 MPa H (and 298 K and 18 MPa H), in comparison with pristine HKUST-1 and impregnated Pd/HKUST-1-IM. It is found that the storage capacity variation is not only ascribed to the different textural properties of materials but is also illustrated by the hydrogen spillover induced by different electron transport from Pd to the pores of MOFs (Pd@HKUST-1-DS > Pd/HKUST-1-IM), based on X-ray photoelectron spectroscopy and temperature desorption spectra. Pd@HKUST-1-DS, featuring high specific surface area, uniform Pd NP dispersion and strong interaction of Pd with hydrogen in the confined pore spaces of the support, displays the high hydrogen storage capacity. This work highlights the influence of spillover caused by Pd electron transport on the hydrogen storage capacity of metal NPs/MOFs, which is governed by both physical and chemical adsorption.
大量研究致力于开发具有高储氢容量且在室温下具有高释氢压力的金属纳米颗粒（NP）掺杂多孔材料。采用超声辅助双溶剂法（DSA）进行样品合成。在本研究中，微小的钯纳米颗粒被限制在HKUST-1的孔道空间内，得到Pd@HKUST-1-DS，使钯纳米颗粒的聚集最小化，进而避免在HKUST-1外表面形成钯纳米颗粒。实验数据表明，与原始HKUST-1和浸渍法制备的Pd/HKUST-1-IM相比，所制备的钯纳米颗粒掺杂的Pd@HKUST-1-DS在77 K和0.2 MPa氢气（以及298 K和18 MPa氢气）条件下具有3.68 wt%（以及1.63 wt%）的出色储氢容量。基于X射线光电子能谱和温度脱附光谱发现，储氢容量的变化不仅归因于材料不同的织构性质，还可由钯向金属有机框架（MOF）孔道的不同电子转移所诱导的氢溢流现象来解释（Pd@HKUST-1-DS > Pd/HKUST-1-IM）。Pd@HKUST-1-DS具有高比表面积、均匀的钯纳米颗粒分散性以及在载体受限孔道空间内钯与氢的强相互作用，展现出高储氢容量。这项工作突出了钯电子转移引起的溢流对金属纳米颗粒/金属有机框架储氢容量的影响，这一影响受物理吸附和化学吸附共同作用。
