Optimizing Hybridization of 1T and 2H Phases in MoS2Monolayers to Improve Capacitances of Supercapacitors

We report on a 100-fold capacitance increase in MoS2-based supercapacitors achieved via optimizing the in-plane 1T-2H phase hybridization of the monolayers. Chemically exfoliated MoS2 monolayers were annealed at low temperature to tune their 1T content from 2% to 60%. The obtained hybridization states were confirmed by X-ray photoelectron and Raman spectroscopies. After optimizing the hybridization degree, the electrode based on MoS2 monolayers with 40% of the 1T phase exhibited outstanding performance with a resistance as low as 0.68 kΩ sq−1, specific capacitance of 366.9 F g−1, and retention ratio of 92.2% after 1000 cycles at current densities of 0.5 A g−1.