Fig. 3: High-resolution XPS spectroscopic detection results for the samples.

a The high-resolution XPS spectra of the BaSO₄ and MBZ for Ba 3d. b The high-resolution XPS spectra of the BaSO₄, MoS₂, and MBZ for S 2p. c The high-resolution XPS spectra of the MoS₂ and MBZ for Mo 3d. d The high-resolution XPS spectra of the BaSO₄ and MBZ for O 1s.