X-ray photoelectron spectroscopy for sulfide glass electrolytes in the systems Li<sub>2</sub>S–P<sub>2</sub>S<sub>5</sub> and Li<sub>2</sub>S–P<sub>2</sub>S<sub>5</sub>–LiBr

X-ray photoelectron spectra of S 2p and P 2p were obtained for the xLi 2 S(100 x)P 2 S 5 (x = 70, 75 and 80 mol %) glasses prepared by mechanochemical treatment. A peak deconvolution technique was used to separate the S 2p spectra into three sulfur components of bridging sulfur (S 0 ), non-bridging sulfur (S ) and sulfide ion (S 2 ) with different photoelectron binding energies. The fractions of sulfurs at different electronic states were obtained from the area ratio of each peak. No apparent difference in the P 2p spectra was observed in the glasses. In the (100 y)(0.7Li 2 S0.3P 2 S 5 )yLiBr (y = 0, 5, 10 and 20 mol %) glasses, the fractions of S 0 and S were almost the same in each glass regardless of the amount of added LiBr content. The addition of LiBr did not affect the electronic state of sulfur in the Li 2 SP 2 S 5 LiBr glasses.