Abstract Benzene-bridged periodic mesoporous organosilicas (PMOs) are functionalized with carboxylic acid (−COOH) groups and used as the supports to immobilize Pd nanoparticles (Pd NPs). It is found that the −COOH functional groups play an important role in controlling the dispersion and growth of Pd NPs. Pd@PMOs are employed as the catalyst for hydrogen generation from hydrolysis of ammonia borane (AB) which shows turnover frequency (TOF) of 30.08 m o l H 2 m o l P d - 1 m i n - 1 and activation energy of 34.9 kJ mol−1. The higher catalytic activity can be attributed to the small size and high dispersion of Pd NPs caused by the strong electrostatic interactions between the negatively charged carboxylate groups in the support and the positively charged Pd2+, favorable textural properties, and intrinsic hydrophobic property of the PMO s due to the presence of benzene groups inside the pore walls. The catalyst shows high durability since metal leaching is not a problem during recycling.

中文翻译：

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包封在羧酸官能化周期性介孔有机二氧化硅中的钯纳米粒子作为高效且可重复使用的多相催化剂，用于氨硼烷制氢

摘要 苯桥连的周期性介孔有机二氧化硅 (PMOs) 被羧酸 (-COOH) 基团官能化，并用作固定 Pd 纳米粒子 (Pd NPs) 的载体。发现-COOH官能团在控制Pd NPs的分散和生长方面起着重要作用。Pd@PMOs 用作氨硼烷 (AB) 水解制氢的催化剂，其转换频率 (TOF) 为 30.08 mol H 2 mol P d - 1 min - 1，活化能为 34.9 kJ mol-1。较高的催化活性可归因于载体中带负电荷的羧酸根与带正电荷的 Pd2+ 之间的强静电相互作用导致 Pd NPs 的小尺寸和高分散性，有利的结构特性，由于孔壁内苯基团的存在，PMO 具有固有的疏水性。该催化剂显示出高耐久性，因为在回收过程中金属浸出不是问题。