Alberti Sebastián, Steinberg Paula Y, Giménez Gustavo, Amenitsch Heinz, Ybarra Gabriel, Azzaroni Omar, Angelomé Paula C, Soler-Illia Galo J A A
Gerencia Química - Centro Atómico Constituyentes , Comisión Nacional de Energía Atómica, CONICET , Avenida General Paz 1499 , 1650 San Martín , Buenos Aires , Argentina.
Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas (INIFTA) - Universidad Nacional de La Plata - CONICET , CC 16 Suc. 4 , 1900 La Plata , Buenos Aires , Argentina.
Langmuir. 2019 May 14;35(19):6279-6287. doi: 10.1021/acs.langmuir.9b00224. Epub 2019 May 6.
Mesoporous oxide thin films (MOTF) present very high surface areas and highly controlled monodisperse pores in the nanometer range. These features spurred their possible applications in separation membranes and permselective electrodes. However, their performance in real applications is limited by their reactivity. Here, we perform a basic study of the stability of MOTF toward dissolution in aqueous media using a variety of characterization techniques. In particular, we focus in their stability behavior under the influence of ionic strength, adsorption of electrochemical probes, and applied electrode potential. Mesoporous silica thin films present a limited chemical stability after electrochemical cycling, particularly under high ionic strength, due to their high specific surface area and the interactions between the electrochemical probes and the surface. In contrast, TiO or SiZrO matrices present higher stability; thus, they are an adequate alternative to produce accessible, sensitive, and robust permselective electrodes or membranes that perform under a wide variety of conditions.
介孔氧化物薄膜（MOTF）具有非常高的比表面积和纳米范围内高度可控的单分散孔隙。这些特性促使它们在分离膜和选择性渗透电极方面具有潜在应用。然而，它们在实际应用中的性能受到其反应性的限制。在此，我们使用多种表征技术对MOTF在水性介质中的溶解稳定性进行了基础研究。特别是，我们关注其在离子强度、电化学探针吸附和施加电极电位影响下的稳定性行为。介孔二氧化硅薄膜在电化学循环后，特别是在高离子强度下，由于其高比表面积以及电化学探针与表面之间的相互作用，化学稳定性有限。相比之下，TiO或SiZrO基体具有更高的稳定性；因此，它们是制备在各种条件下都能工作的可及、灵敏且稳健的选择性渗透电极或膜的合适替代品。
