Transition Metal Carbide Core/Shell Nanoparticles by Ultra-Short Laser Ablation in Liquid

Abstract

Transition metal carbide nanoparticles are a class of technological interesting materials with a wide range of applications. Among metal carbides, tantalum carbides have good compatibility with the biological environment while molybdenum carbides are used as catalyst in electrochemical reactions. Laser ablation of bulk transition metal targets in some liquids is here reported and laser ablation in organic solvents is used as simple synthetic strategy for the production of carbide nanostructures. Herein, the nanoparticles produced by ultra-short laser ablation of tantalum and molybdenum in water, acetone, ethanol and toluene have been characterized by TEM, XRD and XPS analysis. The combined effect of metal and solvent chemical and physical properties on the composition of the nanomaterials obtained has been pointed out. In particular, the different reactivity of Ta and Mo with respect to oxidizing species determines the composition of particles obtained in water, on the other hand the organic solvents decomposition allows to obtain transition metal carbide (TMC) nanoparticles. The observed carbonaceous shell formed on TMC allows to protect the particle’s carbidic core and to improve and tailor the applications of these nanomaterials.

Design and perspective of amorphous metal nanoparticles from laser synthesis and processing

“…Regarding the multicomponent target, it is speculated that the non-congruent vaporization of ejected droplets is produced by short laser pulses, while ultrashort laser pulses have the propensity to highly retain the target stoichiometry. 168 In such case, ps-laser ablation to generate HEA NPs as discussed in Fig. 2e and f shows the well elemental homogeneity for even five elements used.…”

Impact of Chemical and Physical Properties of Organic Solvents on the Gas and Hydrogen Formation during Laser Synthesis of Gold Nanoparticles

“…[20][21][22] However, due to the extreme conditions during the ablation process, the liquid decomposes and reacts with the ablated material. This Reactive Laser Ablation in Liquids (RLAL) has been reported in the past by chemical reactions such as oxidation of the target material [22][23][24] and carbonization [25][26][27] allowing alterations of the structural properties of the gained colloidal nanoparticles. This enables many opportunities [28][29][30] when developing new materials but also challenges when intending to tailor the material properties.…”

Pulsed Laser in Liquids Made Nanomaterials for Catalysis

“…543 The importance of metal carbide interfaces for heterogeneous CO 2 hydrogenation catalysis in the activation of CO 2 was highlighted by Chen et al 330 Tantalum or molybdenum carbide core−shell nanoparticles were prepared by 800 nm, 100 fs pulsed laser ablation of Ta or Mo targets in water, ethanol, toluene, or acetone by Teghil et al 544 Acetone was more effective for making carbides, presumably due to the higher activity of ethanol decomposition products upon ablation, and the shorter plasma lifetime in femtosecond pulsed ablation reduced the risk of oxygen incorporation. 544 A series of metal carbides including TaC was found to catalyze the hydrogen evolution reaction. 545 Porosoff et al identified trends and descriptors for selective CO 2 conversion to CO over transition metal carbides in a careful comparative study.…”

“…Tantalum or molybdenum carbide core–shell nanoparticles were prepared by 800 nm, 100 fs pulsed laser ablation of Ta or Mo targets in water, ethanol, toluene, or acetone by Teghil et al Acetone was more effective for making carbides, presumably due to the higher activity of ethanol decomposition products upon ablation, and the shorter plasma lifetime in femtosecond pulsed ablation reduced the risk of oxygen incorporation . A series of metal carbides including TaC was found to catalyze the hydrogen evolution reaction …”