Nanostructured NiTiO₃as a Catalytic Material for Methanol Electrochemical Oxidation in Alkaline Conditions

Abstract

The electro-catalytic activity of nanostructured nickel titanate (NiTiO 3 ) powders synthesized by a Sol-Gel process was evaluated by means of the electro-oxidation of methanol in alkaline media. In order to correlate the structural, vibrational, morphological and optical properties of the NiTiO 3 powders with their electrochemical activity they were characterized by X-ray diffraction (XRD), Raman spectroscopy, Transmission Electron Microscopy (TEM) and Diffuse Reflectance Spectroscopy (DRS). The powders are formed by nanoparticles of the order of 25 nm. It is shown that the electro-oxidation of methanol in alkaline media is possible in the presence of nanoparticles of this non-noble metal compound, as demonstrated by the current-versus-potential characteristics obtained as a function of methanol concentration. It is shown that the activated Ni atoms at the NiTiO 3 nanoparticles cause a great increase of the electro-oxidation rate of methanol under alkaline conditions. Therefore, this opens the possibility that a layer of nanostructured NiTiO 3 might be used as a catalyst for direct alkaline methanol fuel cells.

Mn-doped Ni(OH)2 Nanostructures as an Efficient Electrocatalyst for Methanol Oxidation in Basic Solution

“…15 Among many transition metal catalysts, Ni-based catalysts are generally considered to have high electrocatalytic activity and are widely studied in energy storage and conversion processes, such as supercapacitors and hydrogen evolution reactions (HER). [16][17][18] Due to its high specific capacitance, wide distribution, low toxicity, and good stability in alkaline electrolytes, Ni(OH) 2 is one of the most widely used nickel-based compounds in the field of electrocatalysis. 19,20 In addition, the introduction of a second metal element in the electrocatalyst provides a significant improvement in the performance of the catalyst.…”

Mechanistic Insights for Photoelectrochemical Ethanol Oxidation on Black Gold Decorated Monoclinic Zirconia

“…Scientists and researchers are showing more interest in the gold nanostructures (Au) for the EOR, as gold is a noble metal, relatively abundant, and electrochemically active . Interestingly, the surface chemistry of gold nanostructures changes drastically, when deposited onto metal oxides such as ZrO 2 , NiTiO 3 , and TiO 2 . , The modified composite materials such as Au/TiO 2 , Au/ZrO 2 , and Au/ZrO 2 –TiO 2 show enhanced electrocatalytic activity toward methanol oxidation . It is worth mentioning that nanostructured gold shows improved electrocatalytic behavior in the alkaline electrolyte as compared to acidic electrolyte because no intermediate poisoning species are formed during the process of oxidation, and also C–C bond cleavage is assisted in alkaline media .…”

Polymorph nickel titanate nanofibers as bifunctional electrocatalysts towards hydrogen and oxygen evolution reactions

“…In this work, we explore the use of polymorph nickel titanate (NTO) as electrocatalyst without compromising the efficiency of HER and OER kinetics attainable by metallic Ni-based systems. Nickel titanate (NTO) heterostructures are known to exhibit superlative performance as electrocatalyst [13][14][15][16] , in addition to their photocatalytic performance for water-splitting applications. [17][18][19] Herein, we report the fabrication of a composite electrode containing the polymorph NTO phases having different crystal structures, namely ilmenite (INTO,NiTiO3) and spinel (SNTO, Ni2.62Ti0.69O4).…”