Nearly atomic precise gold nanoclusters on nickel-based layered double hydroxides for extraordinarily efficient aerobic oxidation of alcohols
Nearly atomic precise gold nanoclusters on nickel-based layered double hydroxides for extraordinarily efficient aerobic oxidation of alcohols
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镍基层状双氢氧化物上的近乎原子精度的金纳米簇可实现极其高效的醇有氧氧化
DOI：
10.1039/c6cy00186f
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发表时间：
2016-06
期刊：
影响因子：
--
通讯作者：
Hui Zhang
中科院分区：
文献类型：
--
作者：
Shuai Wang;Shuangtao Yin;Gaowen Chen;Lun Li;Hui Zhang
通过改进的静电吸附方法，制备了一系列镍基水滑石负载的Au 25纳米团簇催化剂，特别是Au 25/NixAl-LDH（x = Ni/Al，2，3，4）体系。表征结果表明，在六方片状NixAl-LDH（x = 2，3）颗粒的边缘位置上，金团簇的尺寸约为0.9 nm，这是由于其具有较多的Ni-OH位和较强的Au-LDH协同作用，而在不规则的Ni 4Al-LDH（x = 2，3）颗粒上，金团簇的尺寸约为1.1 nm，这是由于其沿着掺杂氧化镍的层状结构较差。在无碱条件下，该催化剂对分子氧选择性氧化1-苯乙醇制苯乙酮具有良好的活性，其活性大小顺序为Au 25/Ni 4Al-LDH <Au 25/Ni 2Al-LDH <Au 25/Ni 3Al-LDH。Au 25/Ni 3Al-LDH在甲苯中的TOF为6780 h-1，在无溶剂中的TOF为118 500 h-1，显示出最高的活性，并且可以应用于广泛的醇，这主要归因于与高度有序的Ni 3Al-LDH层相关的超细金簇和最强的金-LDH相互作用。 在Au 25/NixMn-LDH和Au 25/Ni 3 −xMnxFe-LDH体系中发现了类似的规律性。Au_（25）/Ni_3Al-LDH可重复使用5次而无活性损失。采用最小二乘拟合方法计算了Au_（25）/Ni_xAl-LDH催化剂对1-苯乙醇氧化的反应速率常数（k）和表观活化能（Ea），其大小顺序与反应活性一致。
A series of nickel-based layered double hydroxides supported nearly atomic precise Au25 nanoclusters catalysts, and especially Au25/NixAl-LDH systems (x = Ni/Al, 2, 3, 4) were fabricated via modified electrostatic adsorption of captopril-capped clusters Au25Capt18 onto the predispersed positively-charged NixAl-LDH supports followed by proper calcination. Detailed characterizations show that the ultrafine gold clusters of ∼0.9 nm were well dispersed on the edge sites of hexagonal plate-like particles of NixAl-LDH (x = 2, 3) originated from their ordered LDH layers with more Ni–OH sites and strong Au–LDH synergy, while slightly aggregated to ∼1.1 nm on the irregular Ni4Al-LDH due to its poor layer structure along with doped nickel oxide. The catalysts exhibit excellent activity for selective oxidation of 1-phenylethanol to acetophenone with molecular oxygen under base-free, and the activity follows an increased order of Au25/Ni4Al-LDH < Au25/Ni2Al-LDH < Au25/Ni3Al-LDH. The Au25/Ni3Al-LDH shows the highest activity with TOF of 6780 h−1 in toluene and 118 500 h−1 in solvent-free and can be applied for a wide range of alcohols, mainly ascribed to ultrafine gold clusters and strongest gold–LDH interaction associated with the highly ordered Ni3Al-LDH layers. Similar regularity is found in the Au25/NixMn-LDH and Au25/Ni3−xMnxFe-LDH systems. The Au25/Ni3Al-LDH can be reused 5 times without loss of activity. The least-squares fit analysis yields the rate constant (k) and apparent activation energy (Ea) of Au25/NixAl-LDH catalysts for 1-phenylethanol oxidation, and the order of k and Ea values act in accordance with their reactivities.
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影响因子：
7.3
作者：
Conte, Marco;Carley, Albert F.;Hutchings, Graham J.
通讯作者：
Hutchings, Graham J.
DOI：
10.1002/chin.200701227
发表时间：
2007-01
期刊：
ChemInform
影响因子：
--
作者：
Mingshu Chen;D. Wayne Goodman
通讯作者：
Mingshu Chen;D. Wayne Goodman
DOI：
10.1021/jp950542g
发表时间：
1996-02
期刊：
The Journal of Physical Chemistry
影响因子：
--
作者：
F. Boccuzzi;A. Chiorino;S. Tsubota;M. Haruta
通讯作者：
F. Boccuzzi;A. Chiorino;S. Tsubota;M. Haruta
影响因子：
2.8
作者：
Y. D. Kim;M. Fischer;G. Ganteför
通讯作者：
Y. D. Kim;M. Fischer;G. Ganteför
影响因子：
3.3
作者：
Hui Zhang;Kang-Yu Zou;Shaohua Guo;X. Duan
通讯作者：
Hui Zhang;Kang-Yu Zou;Shaohua Guo;X. Duan