Top: Sulfur K-edge spectra
of (A) the MoSx film as prepared, in the
precatalytic and catalytic states,
together with Mo3S4, MoS2 and MoS3 reference spectra, and (B) the MoSx film poised at 0.3 (black), 0.1 (blue), −0.1 (red),
and −0.3 V (green) in nitric acid at pH = 2. Middle: Molybdenum
L3-edge spectra of (C) the MoSx film as prepared, in the precatalytic and catalytic states, together
with Mo3S4, MoS2, and MoS3 and (D) the MoSx film poised at 0.3
(black), 0.1 (blue), −0.1 (red), and −0.3 V (green)
in nitric acid at pH = 2. Bottom: Molybdenum L2-edge spectra
of (E) the MoSx film as prepared, in the
precatalytic and catalytic states, together with Mo3S4, MoS2, and MoS3 and (F) the MoSx film poised at 0.3 (black), 0.1 (blue),
−0.1 (red), and −0.3 V (green) in nitric acid at pH
= 2.