Efficient and continuous chemical conversion in a thin membrane comprising three-dimensional network trapping Ag nanoparticles
作者：Yuhua Mao , Hao Zhang , Saad Ahmed , Shanshan Li , Shouhao Zhang , Jianli Wang
關(guān)鍵字：Hybrid microgels, Catalytic membrane, Silver nanoparticles, Heterogeneous catalysis, 4-Nitrophenol
論文來源：期刊
具體來源：Applied Catalysis B: Environmental
發(fā)表時間：2022年
在這項工作中，我們報道了一種由分散的銀納米顆粒(NPs)組成的新型高效催化膜(PES/PNM-Ag)。通過動態(tài)加載可膨脹的混合微凝膠PNM-Ag，可以直接構(gòu)建成具有不對稱結(jié)構(gòu)的市售聚醚砜(PES)膜。PNM-Ag和PES/PNM-Ag的表征結(jié)果表明，通過膨脹微凝膠在膜孔中形成了嵌有Ag - NPs的納米級三維網(wǎng)絡(luò)。由PES/PNM-Ag組裝的平板膜反應(yīng)器能夠高效、連續(xù)地催化4-硝基苯酚的還原(表觀反應(yīng)速率常數(shù)達(dá)到1.12 s-1)，且具有良好的穩(wěn)定性。催化活性的提高主要是由于Ag NPs的表面完全可達(dá)以及膜的獨特結(jié)構(gòu)，其中反應(yīng)物在固定催化劑中流動受到限制。本文提出了設(shè)計其他負(fù)載貴金屬NPs的催化膜以高效轉(zhuǎn)化硝基芳香族污染物的策略建議。
In this work, we report a novel and highly efficient catalytic membrane (PES/PNM-Ag) comprising welldispersed silver nanoparticles (NPs). The membrane can be straightforwardly constructed via dynamic loading expansible hybrid microgels PNM-Ag into a commercially-available poly(ether sulfone) (PES) membrane with asymmetric structure. Characterization results of PNM-Ag and PES/PNM-Ag indicate that a nanoscale three-dimensional network embedded with Ag NPs was developed in membrane pores by swollen microgels. The flat-sheet membrane reactor assembled with PES/PNM-Ag can efficiently and continuously catalyze the reduction of 4-nitrophenol (apparent reaction rate constant reaching 1.12 s-1 ) and showed good stability. The improved catalytic activity was attributed to fully accessible surface of Ag NPs as well as the unique structure of the membrane, in which the reactant was restricted to flow through immobilized catalyst. Present strategy hints to design other noble metal NPs loaded catalytic membranes for efficient conversion of nitro-aromatic pollutants.
催化膜的制備和微觀結(jié)構(gòu)的示意圖。
DOI:10.1016/j.apcatb.2022.121456
國家自然科學(xué)基金項目(22178317、22109138)資助。