Sub-10 nm Ag Nanoparticles/Graphene Oxide: Controllable Synthesis, Size-Dependent and Extremely Ultrahigh Catalytic Activity.
Sub-10 nm Ag Nanoparticles/Graphene Oxide: Controllable Synthesis, Size-Dependent and Extremely Ultrahigh Catalytic Activity.
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DOI：
10.1002/smll.201901701
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发表时间：
2019-06
期刊：
影响因子：
13.3
通讯作者：
N. Wang;Bo Guan;Yao Zhao;Ye Zou;Guangwei Geng;Penglei Chen;Fuyi Wang;Minghua Liu
中科院分区：
文献类型：
--
作者：
N. Wang;Bo Guan;Yao Zhao;Ye Zou;Guangwei Geng;Penglei Chen;Fuyi Wang;Minghua Liu
虽然基于银纳米颗粒（AgNP）的材料已经取得了巨大的进步，但开发一种制备尺寸可控和超高性能的亚10纳米银纳米颗粒的简便方案仍然是一个巨大的挑战。结果表明，可以通过光诱导合成来制造带有2.5、4.3和6.2 nm AgNP（分别为2.5-AgNP/GO、4.3-AgNP/GO和6.2-AgNP/GO）的AgNP/氧化石墨烯（AgNP/GO）。研究了它们对4-硝基苯酚（4-NP）还原的催化活性，这是评价贵金属基催化剂性能的“金标准”。当通过摩尔和面积归一化时，活性分别表现出4.3-AgNP/GO> 6.2-AgNP/GO> 2.5-AgNP/GO和6.2-AgNP/GO> 4.3-AgNP/GO> 2.5-AgNP/GO的顺序。这种趋势是GO诱导的电子浓度随着AgNP尺寸减小而降低的结果。值得注意的是，在类似条件下，4.3-AgNP/GO的活性基本上上级于许多现有技术的贵金属基催化剂的活性。AgNP的超细尺寸及其在无封端试剂/覆盖物的无阻碍的2D GO支架上的表面适应性（其使得大量暴露的催化活性位点高度接近底物分子）在其极其可吸收的性能中起重要作用。这项工作为高性能AgNP基材料开辟了一条新的途径，并通过将4-NP还原作为概念验证，为表面基先进材料的合理设计提供了新的科学见解。
While tremendous advancements in Ag nanoparticle (AgNP)-based materials have been made, the development of a facile protocol for preparing sub-10 nm AgNPs with controllable size and ultrahigh performance remains a formidable challenge. It is shown that AgNPs/graphene oxide (AgNPs/GO) bearing 2.5, 4.3, and 6.2 nm AgNPs (2.5-AgNPs/GO, 4.3-AgNPs/GO, and 6.2-AgNPs/GO, respectively) could be fabricated via light-induced synthesis. Their catalytic activity toward 4-nitrophenol (4-NP) reduction, which is a "gold standard" for evaluating the performance of noble metal-based catalysts, is studied. When normalized by mole and area, the activity exhibits an order of 4.3-AgNPs/GO > 6.2-AgNPs/GO > 2.5-AgNPs/GO and 6.2-AgNPs/GO > 4.3-AgNPs/GO > 2.5-AgNPs/GO, respectively. This trend is a result of GO-induced electron concentration reduction with decreasing AgNP size. Significantly, under similar conditions, the activity of 4.3-AgNPs/GO is substantially superior to that of numerous state-of-the-art noble metal-based catalysts. The ultrafine size of the AgNPs and their surface accommodation on the unobstructed 2D GO scaffolds without capping reagents/covers, which make the abundantly exposed catalytically active sites highly accessible to substrate molecules, play an important role in their extremely ultrahigh performance. This work paves a new avenue for high-performance AgNP-based materials, and by taking 4-NP reduction as a proof-of-concept, provides new scientific insights into the rational design of surface-based advanced materials.