Pt stabilization on Pt/SBA-15 through surface modification using MPTMS for sulfuric acid decomposition in SI cycle to produce hydrogen
Pt stabilization on Pt/SBA-15 through surface modification using MPTMS for sulfuric acid decomposition in SI cycle to produce hydrogen
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DOI：
10.1016/j.ijhydene.2019.05.139
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发表时间：
2020-02-21
影响因子：
7.2
通讯作者：
Jung, Kwang-Deog
中科院分区：
文献类型：
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作者：
Khan, Hassnain Abbas;Jaleel, Ahsan;Jung, Kwang-Deog
用于硫酸（SA）分解的催化剂是硫碘（SI）循环中产生氢气的三个反应之一，其应在650-850 ° C的宽温度范围内具有活性和稳定性。铂基催化剂被探索用于SA分解，但它们在850 ℃的高温下遭受严重的Pt损失。均匀的铂纳米颗粒（NP）被物理捕获在以“一锅法”制备的介孔SBA-15的介孔内（Pt-x.x-NTS，x.x：负载的Pt重量%）。使用3-巯基丙基三甲氧基硅烷（MPTMS）作为稳定剂制备其它Pt催化剂以稳定Pt-x.x颗粒（Pt-x.x-TS，x.x：负载的Pt重量%）。一锅法中的共组装方法基于I+M-S+方案，其中S+（质子化嵌段共聚物）和I+（阳离子无机前体）通过M-（PtCW）介体组装在一起。含有硫醇基团的MPTMS用于改性阳离子前体（I+），以便将Pt纳米颗粒保持在介孔通道中，因为还原的铂金属易于与硫醇基团键合。采用XRD、TEM、CO化学吸附、N2吸附脱附和ICP-OES等技术对样品进行了表征。TEM图像显示平均尺寸为7.0（+/-0.84 nm）的小Pt NP均匀地分散在介孔SBA-15上的介孔内。硫醇稳定的Pt-TS催化剂在850 ℃的高温下对硫酸分解显示出优异的催化稳定性。Pt-2.0-NTS在76，000 m（cat）（-1）.h（-1）下50 h的总平均金属损失为67%，而Pt-2.0-TS为16%。Pt/SBA-15的金属损失被显着抑制的表面功能化使用MPTMS在催化剂制备步骤。(C)2019年氢能出版有限责任公司。由爱思唯尔有限公司出版。保留所有权利。
Catalysts for the sulfuric acid (SA) decomposition, one of three reactions in Sulfur Iodine (SI) cycle to produce hydrogen, should be active and stable in wide temperature ranges of 650-850 degrees C. Pt based catalysts are explored for SA decomposition, but they suffered from the severe Pt loss at the high temperature of 850 degrees C. Uniform platinum nanoparticles (NPs) are physically trapped within mesopores of the mesoporous SBA-15 prepared in a "one pot" method (Pt-x.x-NTS, x.x: loaded Pt wt%). Other Pt catalysts are prepared to stabilize Pt-x.x particles using 3-mercaptopropyletrimethoxysilane (MPTMS) as a stabilizing agent (Pt-x.x-TS, x.x: loaded Pt wt%). The co-assembly method in the one pot is based on the I+M-S+ scheme in which S+ (Protonated block copolymer) and I+ (Cationic inorganic precursor) are assembled together through the M- (PtCW mediator. The MPTMS containing thiol group is used to modify the cationic precursors (I+) in order to hold the Pt nanoparticles in mesochannels as the reduced platinum metal is easy to bond with thiol groups. The prepared samples are characterized by XRD, TEM, CO Chemisorption, N-2 adsorption desorption, and ICP-OES techniques. The TEM images show that the small Pt NPs of an average size of 7.0 (+/- 0.84 nm) are uniformly dispersed within the mesopores on the mesoporous SBA-15. The thiol stabilized Pt-TS catalysts display the exceptional catalytic stability for sulfuric acid decomposition at the high temperature of 850 degrees C for 50 h. The overall average metal loss is 67% for the Pt-2.0-NTS for 50 h at 76,000 m(cat)(-1).h(-1), while it is 16% for the Pt-2.0-TS. The metal loss of Pt/SBA-15 is significantly suppressed by the surface functionalization using MPTMS in the catalyst preparation step. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.