Diverse methods have been developed for the synthesis of active nanocatalysts involving various heterogeneous catalytic reactions. Thus far, numerous trial-and-error runs have been done to find the effective and practical ways. In the present work, the All-In-One (AIO) reactor system with a well-designed synthesis program, now in pilot stage, was first exploited as a reliable synthesis tool to find the optimum conditions for the production of Ni nanocatalysts. Using an activated charcoal support, active Ni nanoparticles of 7.8–11.8 nm (labeled A001–A007 in the program) were produced. These were achieved using a melt-impregnation process, which was controlled by variations in the applied gas (N₂ and H₂) and temperature (400 °C, 450 °C, and 500 °C) used as critical factors in the calcination step. Based on the optimization of the reaction sequence, each Ni nanocatalyst could be prepared within 5 h and 22 min. In particular, the optimum Ni nanocatalyst (A006) with the smallest particle size (7.8 nm), prepared under H₂ flow at 400 °C, exhibits the highest catalytic activity (0.748 mmol_4-NP·g_cat⁻¹·s⁻¹) among the Ni catalysts for 4-nitrophenol (4-NP) reduction to 4-aminophenol (4-AP). This activity is much higher than that of conventional supported Ni nanocatalysts (0.551 mmol_4-NP·g_cat⁻¹·s⁻¹) produced using the wetness method.

已经开发了多种方法来合成涉及各种多相催化反应的活性纳米催化剂。到目前为止，已经进行了多次试错，以找到有效和实用的方法。在目前的工作中，具有精心设计的合成程序的多合一（AIO）反应器系统目前处于中试阶段，首先被用作可靠的合成工具，以寻找生产镍纳米催化剂的最佳条件。使用活性炭载体，生产了 7.8-11.8 nm 的活性镍纳米颗粒（在程序中标记为 A001-A007）。这些是通过熔体浸渍工艺实现的，该工艺由施加的气体（N ₂和 H ₂) 和温度（400 °C、450 °C 和 500 °C）用作煅烧步骤中的关键因素。基于反应顺序的优化，每个镍纳米催化剂可以在 5 小时和 22 分钟内制备。特别是在400 ℃的H ₂流下制备的具有最小粒径（7.8 nm）的最佳Ni纳米催化剂（A006）表现出最高的催化活性（0.748 mmol _4-NP ·g _cat ^-1 ·s ^-1 ) 用于将 4-硝基苯酚 (4-NP) 还原为 4-氨基苯酚 (4-AP) 的 Ni 催化剂。该活性远高于使用湿法生产的常规负载型Ni纳米催化剂(0.551 mmol _4-NP ·g _cat ^-1 ·s ^-1 )。