Electrodeposition of Ruthenium-Doped Manganese Selenide for Energy-Related Materials

Selenium-based nanomaterials have attracted considerable attention for electrochemical hydrogen evolution and storage, fuel-cell catalysts, batteries, and electrochemical supercapacitors [1]. Among different selenium-based compounds, manganese selenide seems to be very interesting due to its magnetic and semiconducting properties. These properties are especially important in energy conversion and storage devices, electrochemical and gas sensors, and electrochromic devices [2]. The strong electrochemical properties of metal selenides can be improved by the introduction of ruthenium clusters [3]. Many different methodologies have been used to obtain different Mn-Se nanostructures [2]; however, it seems that electrochemical techniques [1,4] are especially promising due to its simplicity, low-cost, and the possibility of controlling the composition, dimension, morphology, etc., of obtained materials. Unfortunately, there are limited literature reports devoted to the electrodeposition of those materials using a single bath solution. Therefore, this work is aimed at studying the influence of electrodeposition conditions (i.e., type of solvent, bath concentration, electrodeposition potential/current and duration, and hydrodynamic conditions in the electrolytic cell) on the morphology, chemical composition, structure, and electrochemical properties of manganese selenide and ruthenium-decorated manganese selenide. Manganese selenide and Ru-decorated manganese selenide have been electrodeposited onto the nickel foam using aqueous and non-aqueous (based on a mixture of choline chloride and ethylene glycol) baths containing (CH2COO)2Mn and SeO2 without or with the addition of RuCl3. Before electrodeposition, the reduction potentials were determined using linear sweep voltammetry (LSV) and differential pulse voltammetry (DPV). The morphology, chemical composition, and structure of as-obtained films were characterized using a field emission electron microscope (FE-SEM) coupled with an EDS analyzer system. X-ray powder diffraction (XRD) analysis was also performed. Acknowledgments This work was supported by the National Science Centre, Poland (Project no. 2017/26/M/ST5/00715). References: [1] S. Sahoo, P. Pazhamalai, K. Krishnamoorthy, S.-J. Kim, Hydrothermally Prepared α-MnSe Nanoparticles as a New Pseudocapacitive Electrode Material for Supercapacitor. Electrochimica Acta 2018, 268, 403–410. [2] F. Qiao, L. Chen, X. Li, L. Li, S. Ai, Peroxidase-like Activity of Manganese Selenide Nanoparticles and Its Analytical Application for Visual Detection of Hydrogen Peroxide and Glucose. Sensors and Actuators B: Chemical 2014, 193, 255–262. [3] M. Wang, Z. Dang, M. Prato, U. Petralanda, I. Infante, D.V. Shinde, L. De Trizio, L. Manna, Ruthenium-Decorated Cobalt Selenide Nanocrystals for Hydrogen Evolution. ACS Applied Nano Materials 2019, 2, 5695–5703. [4] N. Jiang, B. You, M. Sheng, Y. Sun, Electrodeposited Cobalt-Phosphorous-Derived Films as Competent Bifunctional Catalysts for Overall Water Splitting. Angewandte Chemie International Edition. 2015, 54 (21), 6251–6254.