Bandgap Engineering for Photocatalytic Polymerization of 3, 4‐Ethylenedioxythiophene (EDOT) over Cs3BixSb(2‐x)Br9 Inverse Opals

Abstract A series of all‐inorganic lead‐free halide perovskite inverse opals were prepared and furtherly used as the photocatalysts to promote the polymerization of 3, 4‐ethylenedioxythiophene (EDOT) under the irradiation of visible light. All the samples exhibited the nice replica of the artificial template and high crystallinity. The bandgap of the catalysts was adjusted by screening the ratios of bromide to iodide and antinomy to bismuth, respectively. Among all the samples, Cs 3 Bi 0.5 Sb 1.5 Br 9 inverse opal showed the best catalytic performance and the excellent stability in terms of the morphology and the crystalline phase after four cycles of photocatalytic polymerization. Since EDOT is commercially available, the present observation suggested a convenient protocol of preparing the composited materials or optoelectronic devices based on the lead‐free halide perovskites and the conductive poly(3, 4‐ethylenedioxythiophene).