ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Adsorption of arsenide through functionalized optical fiber: a finite model in silico approach as a perspective for sensing application

Daniel Jauregui-Vazquez, Faustino Aguilera-Granja, and Erik Díaz-Cervantes

División de Ingenierías Campus Irapuato Salamanca, Departamento de Ingeniería Electrónica, Universidad de Guanajuato, Salamanca, Guanajuato, Mexico

E-mail: e.diaz@ugto.mx

Received: 18 August 2021  Accepted: 6 December 2021

Abstract:

The state-of-the-art, related to functionalization of based-silica optical fibers (OF), shows several relevant works. Here, numerous kinds of biopolymers are linked to the optical fiber with some bridge molecules APTES. However, it is clear that to propose a suitable sensor based on optical fibers, it is still necessary to understand this kind of system's molecular and electronic behavior. With this aim, the present work proposes studying the molecular and electronic interactions present in the functionalization of the OF with calcium alginate, using APTES as a molecular bridge between them. Simultaneously, particular interest has been paid to arsenide adsorption on these kinds of molecules. Furthermore, the ion-exchange reaction and two arsenide species, As⁺, As²⁺, As³⁺, and As⁵⁺, receive particular importance in the health and environmental fields. The results show that the functionalization process is possible with a reaction energy of −6.58 eV. However, it is clear that this step is lower in energy and can be consequently promoted. On the other hand, the results show an As⁵⁺ selectivity for the proposed APTES-Alginate-Ca⁺ system, considering an ion-exchange reaction with −5.26 eV of reaction energy, and demonstrate that the As⁵⁺ adsorption is due to the electronic stabilization in the molecular system, as well as due to its binding energy. These results indicate an experimental perspective to perform arsenide detectors based on functionalized optical fibers.

Keywords: Optical-fiber; DFT; APTES; Alginate; As-adsorption

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-021-02013-y

Chemical Papers 76 (4) 2259–2266 (2022)