Mechanochemically assisted synthesis and visible light photocatalytic properties of lanthanum nickel oxide nanoparticles

Abstract

Perovskite-type lanthanum nickel oxide (lanthanum nickelate, LaNiO3) nanoparticles with high photocatalytic activity were synthesized via a mechanochemical route. A high-energy planetary ball mill was employed for mechanochemical preparation of an activated precursor of LaNiO3 via a solid-state reaction of LaCl3, NiCl2, and NaOH. The mechanochemical treatment was performed for 1 h at a revolution speed of the milling pot of 600 rpm. In comparison to an un-milled precursor, a simple mixture of La(OH)3, Ni(OH)2, and NaCl, the activated precursor demonstrated that the mechanochemical treatment contributes to the formation of LaNiO3 at low temperatures. This effect, in turn, leads to reduction of the optical band gap, i.e., enhancement of the visible light photocatalytic activity. Standard characterization techniques confirmed that crystalline round LaNiO3 nanoparticles with a median diameter of 46 nm, a surface area of 23 m 2 /g, and an optical band gap of 1.09 eV were obtained after calcination of the mechanochemically treated precursor at 873 K for 1 h. The visible-light-driven 2 photocatalytic activity was evaluated based on the photodegradation of methyl orange in an aqueous solution. The LaNiO3 catalyst nanoparticles efficiently decomposed methyl orange more than 99% of methyl orange was removed from the solution in 2 h, indicating that the LaNiO3 nanoparticles possess good photocatalytic properties.

Environmentally Friendly Green Synthesis of Fine Particles by Dry Mechanical Processes Toward SDGs: A Review

“…The low-temperature solvent-free method using urea hydrolysis may also be applicable to the environmentally friendly synthesis of other metal oxide nanoparticles. As an effective technique, dry mechanochemical pretreatments for activating the precursor of chemical reaction by thermal treatments, such as heating (Çolak et al, 2017;Iwasaki et al, 2016;Suetsugu, 2014), calcination (Ashiri, 2016;Bulina et al, 2017;Hashimoto et al, 2020;Kosova and Semykina, 2019;Lejda et al, 2020;Liu et al, 2020;Qiu Fig. 9 Relationship between the reaction rate constant and the reciprocal of a parameter representing the kinetic energy of particles.…”

Visible‐light‐driven photocatalytic efficiency of Co‐ and Gd‐doped LaNiO 3 and effect of doping on photochemical, electrochemical, and ferroelectric properties

“…Iwasaki et al prepared LaNiO 3 by facile mechanochemical method at low temperature with band gap value of 1.09 eV, which showed promising PCA for methyl orange under visible light irradiation. Within 2 hours, 95% of dye degradation was achieved, which is an excellent PCA under visible light 26 . Aman et al prepared LaNiO 3 NPs via reverse micro‐emulsion route.…”

“…Within 2 hours, 95% of dye degradation was achieved, which is an excellent PCA under visible light. 26 Aman et al prepared LaNiO 3 NPs via reverse micro-emulsion route. In view of low band gap, LaNiO 3 PCA for the degradation of naphthalene under visible light was excellent.…”

Sonochemically Prepared Ni-Based Perovskites as Active and Stable Catalysts for Production of COx-Free Hydrogen and Structured Carbon

“…66 The possibility also exists that the reaction of the La 3+ cation with either the hydroxyl species or NaOH generates some of the La(OH) 3 that is observed. 67 Physically, ultrasound aids in controlling the crystallite size, composition, and morphology through a variety of mechanisms, including enhanced mixing and interparticle collisions as the particle size increases. 68 Typically, particle size increases with increasing sonication time until interparticle collisions cause fracturing and a reduction in size.…”

“…Reduction of the hydroxyl radicals (2.7 eV) generates hydroxide ions and allows for the oxidation of Ni­(+2) to Ni­(+3) in the oxo-hydroxo species, which is the purported oxidation state of nickel in the ultimate perovskite . The possibility also exists that the reaction of the La 3+ cation with either the hydroxyl species or NaOH generates some of the La­(OH) 3 that is observed . Physically, ultrasound aids in controlling the crystallite size, composition, and morphology through a variety of mechanisms, including enhanced mixing and interparticle collisions as the particle size increases .…”