Fabrication of microsphere-like Bi 3 O 4 Cl/BiOI Z-scheme heterostructure composites and its enhanced photocatalytic per

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Fabrication of microsphere‑like ­Bi3O4Cl/BiOI Z‑scheme heterostructure composites and its enhanced photocatalytic performance for degradation of MO and RhB Liangliang Cheng1 · Xinyan Xiao1 · Yi Wang1 · Mingli Lu1 Received: 18 June 2020 / Accepted: 1 August 2020 © Springer Nature B.V. 2020

Abstract Microsphere-like ­Bi3O4Cl/BiOI Z-scheme heterostructure photocatalysts with improved photocatalytic performance were synthesized by hydrothermal method. SEM images showed that ­Bi3O4Cl had morphological regulation effect on BiOI, which could greatly increase the active sites of the composites. And a possible process for the change of morphology was put forward. Two dyes with different charging properties (MO and RhB) were selected to evaluate the activities of the prepared photocatalysts. As a consequence, the 10%Bi3O4Cl/BiOI composite showed 99.8% of the degradation efficiency for MO degradation in 90  min of simulated sunlight irradiation, the degradation rate constant (0.0577  min−1) was 28.9 and 5.5 times higher than that of pure B ­ i3O4Cl and BiOI, respectively. Similarly, the 10%Bi3O4Cl/ BiOI composite had more superior photocatalytic performance than pure B ­ i3O4Cl and BiOI. The enhancement of photocatalytic performance was mainly attributed to the increased light absorption, charge separation efficiency and specific surface area, which was proved by DRS, PL, EIS and N ­ 2 adsorption–desorption characterizations. Further, the radical trapping experiments confirmed that holes ­(h+) and superoxide radicals (·O2−) were the main active species for the photodegradation. Combining with the DRS and trapping experiments, a possible Z-scheme heterojunction photocatalytic mechanism was proposed. Keywords Bi3O4Cl/BiOI microsphere · Morphological regulation effect · Z-scheme heterostructure · Photocatalysis

* Xinyan Xiao [email protected] 1



School of Chemistry and Chemical Engineering, Guangdong Provincial Key Lab of Green Chemical Product Technology, South China University of Technology, Guangzhou 510640, China

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Introduction Recently, people around the world are facing with serious environmental pollution and energy crisis, resulting from rapid development of science, technology and industry. The technology of semiconductor photocatalysis can make use of rich solar energy and generate active species to degrade contaminants and achieve energy conversion, which has been gained much attention [1–3]. Among various semiconductor photocatalysts, bismuth oxyhalides (BiOX, X = Cl, Br and I) with layered structures have arisen much interest because of its complicated band structures and unique layered structures [4, 5]. ­Bi3O4Cl, belongs to the Sillén family compounds, consisting of ­[Bi3O4] and interleaved halogen-ion layers, and this distinctive crystalline structure can offer enough space to polarize the relevant atoms and orbitals, forming self-built internal electrostatic field. The formed field can facilitate the separation and transport of charge carriers and improve the pho