Centro de Investigación y Desarrollo Tecnológico en Electroquímica

About: Centro de Investigación y Desarrollo Tecnológico en Electroquímica is a based out in . It is known for research contribution in the topics: Cyclic voltammetry & Catalysis. The organization has 537 authors who have published 682 publications receiving 10382 citations. The organization is also known as: Centro de Investigacion y Desarrollo Tecnologico en Electroquimica & Center of Research and Technologic Development in Electrochemistry.

UV–Vis spectroscopical and electrochemical detection of La3+, Ce4+ and Nd3+ in aqueous media using modified graphite electrodes

Abstract: This paper shows a comparison and discussion of the detection results, by spectrophotometric and electrochemical methods, for La3+, Ce4+ and Nd3+ in aqueous medium. The obtained values of detection and quantification limit of cerium and neodymium by the spectrophotometric method were 1.7E−5 and 5.5E−5 M and 0.7 and 2.3 M respectively. However, a lanthanum signal was not detect in a 200–900 nm wavelength range. The cyclic voltammetry electrochemical method was also tested. It employed graphite, modified graphite electrode with Cyclam and modified graphite electrode with Phthalocyanine as working electrode in the electrochemical cell. The lowest values of detection and quantification limit of lanthanum and neodymium 1.6E−7 and 5.9E−7 M and 1.7E−7 and 5.9E−7 M respectively were obtained with pre-functionalized electrodes at 1.6 V and modified with Phthalocyanine by immersion; indicating that the electrochemical method provides greater sensitivity in the detection and quantification limits than the spectrophotometric method for these species. The feasibility of applying modified graphite as working electrode to detect actinides in an electrochemical method provides a new isotopic characterization technique. This technique would improve efficiency for radioactive compounds management in the aqueous systems of a nuclear reactor, which is considered the fundamental problem in the use of nuclear energy.

Influence of EDTA on the Electrochemical Removal of Mercury (II) in Soil from San Joaquín, Querétaro, México

Abstract: The removal of mercury from soil and Ca-bentonite was performed using electrochemical treatment adding ethylendiamine- tetra acetic acid (EDTA) as a complexing agent to improve the elec- trochemical removal of Hg (II) in soil from San Joaquin, Queretaro, Mexico. During the electrokinetic treatment in the presence of 0.1 M EDTA, most of Hg (II) migrates toward the anode obtaining the high- est removal efficiencies close to 70 % in bentonite after 9 h. Using 0.1M HCl only 65 % efficiency was attained after 13 h in the cathodic side. EDTA formed a negatively charged stable complex that migrates to the cathode by the application of the electrokinetic treatment across Hg - EDTA synthesized complex.

A Range of Nitrato Coordination Modes in NiII Complexes with the Versatile Ligand 1,8-Bis(2-pyridyl)-3,6-dithiaoctane: Structural, Spectroscopic, Electrochemical, and Theoretical Studies

Abstract: We have synthesized a series of NiII-pdto complexes – [Ni(pdto)(NO3)]NO3·H2O (C1), [Ni(pdto)(H2O)2](NO3)2 (C2), and [Ni(pdto)(NO3)(H2O)]NO3 (C3), with pdto = 1,8-bis(2-pyridyl)-3,6-dithiaoctane – with different spectroscopic responses associated with the coordination modes of the nitrato moiety. Through UV/Vis spectroscopy and electrochemical experiments it was established that in acetonitrile solution the compounds C1, C2, and C3 are each transformed into the same chemical species [Ni(pdto)NO3]+. Cyclic voltammetry experiments gave evidence of two consecutive one-electron transfers associated with NiII-(pdto) + 1 e– NiI-(pdto) and NiI-(pdto) + 1 e– Ni0 + pdto processes, which are in agreement with the high flexibility of the pdto ligand with regard to accommodating the preferred geometry of the central atom. The complexation reaction between pdto and the starting salt Ni(NO)3·6 H2O in acetonitrile was also studied by UV/Vis spectroscopy and cyclic voltammetry. A linear relationship between the experimentally determined value of 10 Dq and the Δ(EHOMO–LUMO) energy values obtained by computational methods was found.

Silver/Silicon nanowires/copper nanoparticles heterojunction for methyl orange degradation by heterogeneous photocatalysis under visible irradiation

Abstract: In this work, the degradation of methyl orange (MO) was analyzed by direct light with visible radiation (λ > 450 nm) of a dye solution in the presence of silicon nanowires (SiNWs) or silicon nanowires with copper nanoparticles (SiNWs-CuNPs). The SiNWs were synthesized by metal assisted etching from monocrystalline silicon wafers in aqueous HF / AgNO3 solution, and the CuNPs were deposited on the SiNWs via electroless. Discoloration with visible irradiation of aqueous methyl orange solution (C14H14N3NaOS) in the presence of SiNWs showed an efficiency of 71% after 120 min of illumination. The deposition of copper nanoparticles on the nanowires improves the efficiency of the photocatalytic reaction achieving 89% discoloration after 120 min exposure to visible light. The MO photocatalytic degradation with visible radiation in aqueous solution shows to be efficient in discoloration reaching up to 92% in a time of 150 min in the presence of SiNWs-CuNPs