P-026

Rugilė Jurgelionytė

rugile.jurgelionyte@ktu.lt

I. Barauskienė, G. Laukaitis, E. Valatka

Department of Physical and Inorganic Chemistry, Kaunas University of Technology, Lithuania

Electrocatalytic Activity Of Zirconium Nitride In Hydrogen Evolution Reaction

Precious metals, such as Pt or Ir, are the most active electrocatalysts in water electrolysis for the generation of hydrogen. However, their high cost and scarcity are the main factors hindering a large-scale usage of water electrolysis. Therefore, numerous efforts have been made to explore novel electrocatalysts based on earth-abundant elements to diminish the dependence on precious metals [1]. In this field, transition metal nitrides have recently raised a lot of attention due to their unique physicochemical properties. These materials exhibit similar surface and adsorption properties to the VIII group of precious metals, such as Pt and Pd, because the atomic distance between metal atoms increases and the d-band centre downshifts after the incorporation of nitrogen atoms. Transition metal nitrides have high electrical conductivity, high chemical stability, and remarkable mechanical robustness. Combining all these properties, transition metal nitrides show high potential as catalysts for various application areas, such as electrocatalysis, hydrogenation of fuel oil or synthesis of ammonia [2]. 

The purpose of this work was to synthesize ZrN thin films on AISI 304 type stainless steel, study their structure and electrochemical activity in aqueous solution.

Pulse direct current magnetron sputtering was used for ZrN thin film deposition. This method is a fast and efficient way to obtain thin films of desired thickness of about 250 nm. Thin films were deposited from a ZrN target under various conditions by adjusting the Ar/N₂ gas ratio and applying power between 200 and 350 W. The prepared electrocatalyst samples were analyzed using scanning electron microscopy and energy-dispersive X-ray spectroscopy (SEM-EDX), Raman spectroscopy, X-ray diffraction spectroscopy, profilometry, and UV-vis spectroscopy. Electrochemical measurements, including cyclic voltammetry, chronoamperometry, and chronopotentiometry, were conducted in 0.1 M KOH electrolyte using a three-electrode system. This system comprised a ZrN/stainless steel substrate as the working electrode, an Ag/AgCl|KCl(sat) reference electrode, and a Pt wire as the counter electrode. The experimental findings indicated that ZrN/stainless steel electrodes exhibit excellent stability and activity for the hydrogen evolution reaction (HER). Tafel analysis was carried out to understand the HER mechanism and assess the influence of synthesis conditions on the electrocatalytic performance of ZrN thin films.

[1] K. Liu, P. Cao, W. Chen, C. I. Ezeh, Z. Chen, Y. Luo, Q. Liu, H. Zhao, Z. Rui, S. Gao, Z. Yin, X. Sun, X. Yu. Electrocatalysis enabled transformation of earth-abundant water, nitrogen and carbon dioxide for a sustainable future.2022 Mater. Adv. Vol. 3 RSC p. 1359-1400.

[2] Meng, Z.; Zheng, S.; Luo, R.; Tang, H.; Wang, R.; Zhang, R.; Tian, T.; Tang, H. Transition Metal Nitrides for Electrocatalytic Application: Progress and Rational Design. Nanomaterials 2022, 12, 2660.