Synthesis of vertically aligned wafer-scale tantalum disulfide using high-Ar/H ₂ S ratio plasma

This is the authors' abstract. We don't add key points for this paper.

Nanostructural modification of two-dimensional (2D) materials has attracted significant attention for enhancing hydrogen evolution reaction (HER) activity. In this study, the nanostructure of TaS 2 films was controlled by controlling the Ar/H 2 S gas ratio used in plasma-enhanced chemical vapor deposition (PECVD). At a high Ar/H 2 S gas ratio, vertically aligned TaS 2 (V-TaS 2 ) films were formed over a large-area (4 in) at a temperature of 250 °C, which, to the best of our knowledge, is the lowest temperature reported for PECVD. Furthermore, the plasma species formed in the injected gas at various Ar/H 2 S gas ratios were analyzed using optical emission spectroscopy to determine the synthesis mechanism. In addition, the 4 in wafer-scale V-TaS 2 was analyzed by x-ray photoelectron spectroscopy, transmission electron microscopy, and atomic force microscopy, and the HER performance of the as-synthesized TaS 2 fabricated with various Ar/H 2 S ratios was measured. The results revealed that, depending on the film structure of TaS 2 , the HER performance can be enhanced owing to its structural advantage. Furthermore, the excellent stability and robustness of V-TaS 2 was confirmed by conducting 1000 HER cycles and post-HER material characterization. This study provides important insights into the plasma-assisted nanostructural modification of 2D materials for application as enhanced electrocatalysts.