Provided are blue thiophene electrochromic compounds, including 3,4-(2,2-bis(2-oxo-3-phenylpropyl))propylenedioxythiophene, 3,4-(2,2-bis(2-oxo-3-phenylbutyl))propylenedioxythiophene and 3,4-(2,2-bis(2-oxo-3-phenylpentyl))propylenedioxythiophene. The colour of the thiophene electrochromic compounds can be changed between blue and transparency. The thiophene compounds can be electro-polymerized into a film on a surface of an ITO glass, and are characterized in that the driving voltage is low (within ±1V), the response time is short, and the difference between transmittances in a coloured state and in an uncoloured state is large (up to 77.5%). The thiophene electrochromic compounds can be applied to devices such as electrochromic windows, rear view mirrors, electrochromic displays.
BLUE ELECTROCHROMIC COMPOUND, PREPARATION METHOD THEREFOR, AND ASSEMBLY CONTAINING SAME