ABSTRACT
The electrochemiluminescence (ECL) signal is largely determined by the electron transfer efficiency. Therefore, in the nanomaterial-involved ECL system, the structure-related electron distribution could affect the electron transfer efficiency and further alter the ECL intensity. These features make the design of versatile ECL-based analytical techniques for probing the correlated structure possible. And it is generally accepted that the increased crystallinity of nanomaterials usually leads to a uniform electron distribution, which provides higher conductivity. Therefore, the crystallinity-improved conductivity could facilitate electron transfer, promote the electrochemical activity of support materials, and boost the efficiency of the ECL reaction. In this study, we have demonstrated that the ECL signal of the graphitic carbon nitride reporter was proportional to the crystallinity of layered double hydroxides (LDHs), which meets the supposition well. On the basis of this phenomenon, an ECL-based crystallinity analysis approach has been established using CdAl-LDHs as the model materials. The universality of this proposed technique was further validated by the rapid and accurate crystallinity determination of ZnAl-LDH samples with diverse crystallinities. This work not only contributes an alternative to the X-ray diffraction technique for the rapid screening of crystallinity in layered materials but also opens a new avenue for the design of ECL-based structure analysis techniques toward nanomaterials and even organic materials by involving electron transfer regulation correlation.
ABSTRACT
Vesicles as a typical interface-rich microenvironment can promote the reaction rate and the intermediate stability, which are promising for introduction in electrochemiluminescence (ECL) signal amplification. In this work, a kind of multilamellar vesicle obtained from sodium bis(2-ethylhexyl) sulfosuccinate (AOT) was used to modify the electrode surface. The AOT vesicle-modified microenvironment could significantly enhance the ECL performances for the luminol/O2 system in a neutral medium. The mechanism study demonstrated that the nanoscale multilamellar vesicles could maintain the vesicle structure on the electrode surface, which substantially improved the electron transfer and reaction rate, luminescence efficiency of the excited-state 3-aminophthalate anion, and stability of the superoxide anion radical. Alternatively, such a multifunctional microenvironment was also able to enhance the ECL signals from the tris(2,2'-bipyridine)ruthenium(II) (Ru(bpy)32+)/tripropylamine (TPrA) system. Moreover, another dodecyl dimethyl(3-sulfopropyl) ammonium hydroxide inner salt (DSB)-based vesicle was constructed to further verify the versatility of the vesicle-modified microenvironment for ECL signal amplification. Our work not only provides a versatile microenvironment for improving the efficiency of various ECL systems but also offers new insights for the microenvironment construction using the ordered assemblies in ECL fields.
