Pickering Interfacial Catalyst with CO2 and Magnetic Dual-Response for Fast Recovering in Biphasic Reaction
作者：Jun Tang, Xue Zhou, Shixiong Cao, Lingyu Zhu, Lingling Xi, and Jianli Wang*
關鍵字：Biphasic reaction, CO2, magnetic, Pickering interfacial catalysis, recovery
論文來源：期刊
具體來源：ACS Applied Materials & Interfaces
發表時間：2019年
Pickering界面催化作用通過增大反應界面為雙相反應提供了一個良好的平臺，但由于納米催化劑在液-液界面吸附能較高，使得它的分離和回收十分困難。據此提出了一種基于磁性和CO2雙響應的納米復合物Fe3O4@ SiO2 @ P（TMA-DEA）的新型多功能皮克林乳液。 這種納米粒子有助于在雙相體系中形成穩定的油包水（W /O）Pickering乳液，并通過鼓入CO2來實現破乳。在外加磁場的情況下，納米粒子在2分鐘內就可以被輕松捕獲這顯示出其優異的可回收性。 在用于醇氧化的Anelli系統中，與未乳化的兩相相比，Pickering乳液中納米催化劑的催化效率增大了3倍，并且5次循環套用后幾乎沒有活性損失。這種新穎的雙響應系統為有效回收納米催化劑和強化液液雙相反應提供了一種綠色節能的策略。
Pickering interfacial catalysis provides an excellent platform for biphasic reactions, but the separation and recycling of nanocatalyst is a challenge because of high adsorption energy of nanocatalyst at the liquid-liquid interface. In this work, we represent a new type of versatile Pickering emulsion based on magnetic and CO2-responsive nanohybrids Fe3O4@SiO2@P(TMA-DEA). The smart nanoparticles can stabilize the water-in-oil (W/O) Pickering emulsion in biphasic system, and achieve the subsequent demulsification by bubbling CO2 ascribed to their reversible switching surface. In the absence of energy barrier, the nanohybrids can be easily captured in situ by magnetic field in 2 min and showed excellent recyclability. In the Anelli system for alcohol oxidation, the nanocatalyst exhibited threefold enhancement in catalytic efficiency in comparison with unemulsified two-phase, and little loss on activity after 5 cycles. The conceptually novel dual-responsive system offer a green and energy-saving strategy for effective recycling of nanocatalyst and intensification of biphasic reaction.
DOI: 10.1021/acsami.9b00821