Abstract
Abstract
The mixed-phase MoS2 (1T/2H MoS2) with heterostructure exhibited high catalytic activity. The specific ratios of 1T/2H could exhibit optimal performance in various applications. Therefore, more methods need be developed for synthesizing 1T/2H mixed-phase MoS2. Herein, a viable route was studied for the phase transition of 1T/2H MoS2 regulated by H+. Briefly, the commercially available bulk MoS2 was used to obtain 1T/2H MoS2 via chemical intercalation of Li+. Then the residual Li+ around 1T/2H MoS2 was replaced by H+ in acidic electrolytes, owing to the extremely higher charge-to-volume ratio of H+. Thus, the thermodynamically unstable 1T phase lost the protection of residual Li+ and could be re-transforming into the relatively stable 2H phase. The change of the 2H/(2H+1T) ratio was measured using novel extinction spectroscopy, which provides a rapid identification method in comparison with x-ray photoelectron spectroscopy (XPS). The experimental results revealed that the concentration of H+ influenced the phase transition velocity of MoS2. In particular, the phase transition from 1T to 2H phase in the H+ solution was faster at the beginning, and the higher the H+ concentration in an acidic solution, the faster the increase in 2H content. For an instant, the ratio of the 2H phase was increased by 7.08% in an acidic solution (CH
+ = 2.00 M) after 1 h, which was several times greater than the case in the distilled water. This finding provides a promising method to easily obtain different ratios of 1T/2H MoS2, which is beneficial for further development of catalytic performance especially in energy generation and storage.
Funder
Natural Science Foundation of Shandong Province
Taishan Scholar Program of Shandong Province
National Natural Science Foundation of China
Subject
Condensed Matter Physics,General Materials Science