Non-Noble Metal Ni Nanoparticles Supported on Highly Dispersed TiO2-Modified Activated Carbon as an Efficient and Recyclable Catalyst for the Hydrogenation of Halogenated Aromatic Nitro Compounds under Mild Conditions
Non-Noble Metal Ni Nanoparticles Supported on Highly Dispersed TiO2-Modified Activated Carbon as an Efficient and Recyclable Catalyst for the Hydrogenation of Halogenated Aromatic Nitro Compounds under Mild Conditions
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高分散TiO2改性活性炭负载的非贵金属Ni纳米颗粒作为温和条件下卤代芳香硝基化合物加氢的高效且可回收的催化剂
DOI：
10.1021/acs.iecr.9b04397
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发表时间：
2020-01-29
影响因子：
4.2
通讯作者：
Luo, He'an
中科院分区：
文献类型：
--
作者：
Huang, Lei;Lv, Yang;Luo, He'an
制备了TiO 2改性的活性炭负载镍基催化剂（Ni/TiO2@OAC），并将其用于氯代硝基苯（CNB）加氢合成氯代苯胺（CANs）。表征结果表明，TiO 2的引入抑制了镍纳米颗粒的烧结，并通过强的金属-载体相互作用提高了催化剂的稳定性。此外，X射线光电子能谱结果表明，Ti 3+的供电子效应产生富电子的Ni（Ni δ-），这抑制了C-Cl部分吸附。所形成的Ni δ-物种可能诱导富电子氢（H-）的产生，这有利于对-NO2的亲核攻击，而不是对C-Cl键的亲电攻击。此外，由于TiO2@OAC中的-OH与CAN中的-NH 2之间的相互作用，降低了-NH 2的给电子能力。因此，脱氯被抑制，对m-CAN的选择性高达99.0%。Ni/TiO2@OAC催化剂在5次循环后仍能保持催化性能。
TiO2-modified oxygen-functionalized activated carbon (TiO2@OAC)-loaded nickel-based catalysts (Ni/TiO2@OAC) were synthesized and applied in the hydrogenation of chloronitrobenzene (CNB) to chloroanilines (CANs). The characterization results indicate that introduction of TiO2 restrains nickel nanoparticles sintering and improves the stability of the catalysts by strong metal-support interaction. Additionally, the X-ray photoelectron spectroscopy results suggest that the electron donating effect of Ti3+ produces electron-rich Ni (Ni delta-), which inhibits C-Cl moiety adsorption. The formed Ni delta- species might induce electron-rich hydrogen (H-) generation which facilitates a nucleophilic attack on -NO2 rather than an electrophilic attack on the C-Cl bond. Furthermore, the electron-donating ability of -NH2 could be reduced because of the interaction between -OH in TiO2@OAC and -NH2 in CAN. Hence, the dechlorination is inhibited and the selectivity to m-CAN is up to 99.0%. The catalytic performance of Ni/TiO2@OAC could be maintained after five cycles.