Work

Bulk synthesis of mixed transition metal dichalcogenide and performance as working electrode in Li, Na, and K-ion half cells

Year: 2025

Type: article

Abstract: Nanosheets of mixed or cation-substituted Transition metal dichalcogenide (TMD) are promising materials for a range of applications, including electrodes for electrochemical energy storage devices. Yet such materials are expensive to produce in large quantities (gram levels or higher). Here, we report on a two-step process, which involves precursor pyrolysis and sulfur annealing for the preparation of bulk powders of Mo x W1−x S2. The structural and morphological properties of the synthesized cation-substituted TMD alloy are compared with high-purity commercially sourced MoWS2 and MoS2/WS2 hybrid specimens. Notably, the electrochemical characteristics of synthesized Mo x W1−x S2 exhibit exceptional first-cycle specific charge capacities for lithium-ion (638 mAh g−1), sodium-ion (423 mAh g−1), and potassium-ion (328 mAh g−1) half-cells. All the cells showed capacity decay in longer-term cycling tests, arising from volume changes in TMD conversion-type electrodes. To mitigate the capacity decay, a voltage cut-off method is implemented, which minimizes irreversibility and structural distortion of TMD during cycling, even at higher cycling currents with nearly 100% average cycling efficiency. The findings of this study demonstrate a proficient and scalable synthesis methodology poised to be utilized across an array of layered TMD materials, with benefits to both industry and fundamental research into alkali-metal-ion energy storage.

Source: Nanotechnology

DOI: 10.1088/1361-6528/adcf30

Authors: Arijit Roy, Gurpreet Singh

Institution: Kansas State University

Language: English

Topic: Advancements in Battery Materials

Subfield: Electrical and Electronic Engineering

Field: Engineering

Domain: Physical Sciences

SDG: Affordable and clean energy

Open Access status: hybrid

Estimated APC paid: $3,325