Electrosynthesis of MoTe 2 Thin Films: A Combined Voltammetry-Electrochemical Quartz Crystal Microgravimetry Study of Mechanistic Aspects

• Published in: Journal of the Electrochemical Society 2020-01, Vol.167 (11), p.116510
• Main Authors: Myung, Noseung, Park, Hyo-Yoon, Jee, Hyung-Woo, Sohn, Eun Bee, Lee, Su Jin, Paeng, Ki-Jung, Rhee, Insook, Vali, Abbas, Rajeshwar, Krishnan
• Format: Article
• Language: English
• ISSN: 0013-4651; 1945-7111
• DOI: 10.1149/1945-7111/aba15e

Molybdenum telluride (MoTe 2 ) belongs to the family of layered transition metal dichalcogenides (TMDs) with unique optical, optoelectronic, structural properties and potential applications in a wide array of technologies related to solar energy conversion, optoelectronics, lubrication, and hydrogen production. Here, electrodeposition is shown to be a facile method for the synthesis of MoTe 2 in bulk (i.e., not exfoliated) form. The electrosynthesis of MoTe 2 films and the underlying compound formation mechanism were investigated for the first time using linear sweep voltammetry (LSV) combined with electrochemical quartz crystal microgravimetry (EQCM). A Te-modified electrode in an electrolyte containing molybdenum precursor species, a MoO x -modified electrode in tellurium precursor-containing electrolyte and a variety of control experiments were employed to elucidate the electrodeposition mechanism of MoTe 2 films. Electrogeneration of HTe − was the key step in MoTe 2 film formation which occurred by the reaction of electrodeposited MoO x with HTe − generated by electroreduction of Te or HTeO 2 + . Thermodynamic aspects of this reaction are finally presented.