Two-dimensional Bi2O2CO3/δ-Bi2O3/Ag2O heterojunction for high performance of photocatalytic activity

[Display omitted] •The 2D Bi2O2CO3/δ-Bi2O3 structure is achieved by a composite-salt mediated approach.•2D Bi2O2CO3/δ-Bi2O3 network exhibits an excellent adsorption capacity.•The Bi2O2CO3/δ-Bi2O3/Ag2O composite exhibits an excellent photocatalytic performance. Two-dimensional layered materials have attracted extensive interest recently due to their high efficiency solar energy conversion. However, 2D layered materials are usually stacked by individual monolayers through strong chemical bonds or van der Waal interactions. Therefore, it is still challenging to fabricate to 2D monolayered materials. Herein, monolayered Bi2O2CO3 composition dotted with δ-Bi2O3 assembling to a network structure is fabricated through a simple composite-salt mediated approach, which has strong adsorption of organic pollutant. After loaded Ag2O on the surface of it, Bi2O2CO3/δ-Bi2O3/Ag2O (BBA) composite exhibits a lower adsorption capability but higher photodegradation efficiency for methylene blue (MB). 97% MB is degraded by BBA-3 in 15 min under the irradiation of simulated sunlight of 100 mW/cm2, much better than that of commercial TiO2 (P25) and Bi2O2CO3/δ-Bi2O3. The short diffusion distance in the two-dimensional structure enables photoexcited carriers to diffuse to the surfaces almost without recombination and leads to efficient photodegradation of dyes on both sides of a monolayer or few layers. This novel 2D structure brings a new idea for developing highly efficient photocatalyst.