gamma-Radiation synthesis of ultrasmall noble metal (Pd, Au, Pt) nanoparticles embedded on boron nitride nanosheets for high-performance catalysis
gamma-Radiation synthesis of ultrasmall noble metal (Pd, Au, Pt) nanoparticles embedded on boron nitride nanosheets for high-performance catalysis
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γ-辐射合成嵌入氮化硼纳米片的超小型贵金属（Pd、Au、Pt）纳米粒子，用于高性能催化
DOI：
10.1016/j.ceramint.2021.05.327
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发表时间：
2021
影响因子：
5.2
通讯作者：
Lin Mingzhang
中科院分区：
文献类型：
--
作者：
Wang Yi;Chen Jialiang;Wang Lan;Weng Hanqin;Wu Zhihao;Jiao Limin;Muroya Yusa;Yamashita Shinichi;Cheng Sheng;Li Fuhai;Chen Hongbing;Huang Wei;Lin Mingzhang
超小尺寸贵金属纳米催化剂的大规模合成和稳定化是其实际应用的关键。本文采用60 Co γ射线辐照诱导前驱体盐还原的方法，将Pd、Au和Pt纳米粒子原位包埋在氮化硼纳米片上。通过脉冲辐解实验阐明了还原机理。与六方BN（h-BN）等其他BN基板相比，BNNSs不仅具有263 m2 g-1的大表面积，而且在超声波剥离过程中产生大量羟基，从而导致超小尺寸，大负载量和均匀分布的锚定NP。负载的Pd、Au和Pt NP的粒径分别测量为2.9、3.1和3.0 nm。结果表明，在2-硝基苯胺还原反应中，Pd-、Au-和Pt-BNNSs复合纳米催化剂的催化活性明显高于其他BN载体上负载相应纳米粒子的催化活性.特别地，当使用Pd-BNNSs作为催化剂时，大部分2-硝基苯胺可以在仅仅40 s内被还原，执行1.1 × 10− 1 s −1的速率常数。延长超声剥离时间可以提高BNNSs载体上羟基的数量以及相应的NPs负载BNNSs复合材料的催化性能，因为更多的NPs负载和羟基也被证明在提高催化活性方面起着重要作用。此外，由于BNNSs的高稳定性和它们对PdNPs的强亲和力，Pd-BNNSs催化剂即使在5次循环后仍然显示出突出的活性。本工作不仅证明了BNNSs是负载贵金属NPs催化的理想载体，而且揭示了通过γ辐照在BNNSs上原位合成和包埋超小贵金属NPs的可行性。
The large-scale synthesis and the stabilization of noble metal nanocatalysts with ultrasmall sizes are crucial to their practical application. Herein, Pd, Au, and Pt nanoparticles (NPs) arein situembedded on boron nitride nanosheets (BNNSs)viathe reduction of precursor salts induced by60Co γ-irradiation, which is a mature technique widely used in industry. The reduction mechanism was elucidated by pulse radiolysis experiments. In comparison with other BN substrates like hexagonal BN (h-BN), BNNSs had not only large surface area of 263 m2g−1, but also abundant hydroxyl groups produced during the sonicated exfoliation, resulting in ultrasmall sizes, large loading amounts, and uniform distribution of the anchored NPs. The particle sizes of the loaded Pd, Au, and Pt NPs were measured to be 2.9, 3.1, and 3.0 nm, respectively. As a consequence, in the model reaction of 2-nitroaniline reduction, the Pd-, Au- and Pt-BNNSs composite nanocatalysts showed much higher catalytic activities than those composites loading the corresponding NPs on other BN substrates. Particularly, most of the 2-nitroaniline could be reduced within merely 40 s when using Pd-BNNSs as catalysts, performing a rate constant of 1.1 × 10−1s−1. The number of hydroxyl groups on BNNSs support as well as the catalytic performance of the corresponding NPs-loaded BNNSs composites could be improved by extending the sonicated exfoliation time, because more NPs were loaded and the hydroxyl groups were also proved to play an important role in enhancing the catalytic activity. Moreover, Pd-BNNSs catalysts still displayed prominent activity even after five cycles owing to the high stability of BNNSs and their strong affinity for PdNPs. This work not only demonstrates BNNSs as ideal supports to load noble metal NPs for catalysis, but also reveals the feasibility to synthesize andin situembed ultrasmall noble metal NPs on BNNSsviaγ-irradiation.