Two‐Step Oxidation Synthesis of Sulfur with a Red Aggregation‐Induced Emission. Issue 25 (29th January 2020)

• Record Type: Journal Article
• Authors: Wang, Zhenguang; Zhang, Chuanchuan; Wang, Henggang; Xiong, Yuan; Yang, Xinjian; Shi, Yu‐e; Rogach, Andrey L.
• Is Part Of: Angewandte Chemie international edition. Volume 59:Issue 25(2020)
• Page Start: 9997
• Page End: 10002
• Publication Date: 2020-01-29
• Subjects: aggregation-induced emission -- elemental sulfur -- oxidation -- oxygen vacancies -- phosphorescence; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201915511
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: Sulfur is not normally considered a light‐emitting material, even though there have been reports of a dim luminescence of this compound in the blue‐to‐green spectral region. Now, it is shown how to make red‐emissive sulfur by a two‐step oxidation approach using elemental sulfur and Na2 S as starting materials, with a high photoluminescence quantum yield of 7.2 %. Polysulfide is formed first and is partially transformed into Na2 S2 O3 in the first step, and then turns back to elemental S in the second step. The elevated temperature and relatively oxygen‐deficient environment during the second step transforms Na2 S2 O3 into Na2 SO3 incorporated with oxygen vacancies, thus resulting in the formation of a solid‐state powder consisting of elemental S embedded in Na2 SO3 . It shows aggregation‐induced emission properties, attributed to the influence of oxygen vacancies on the emission dynamics of sulfur by providing additional lower energy states that facilitate the radiative relaxation of excitons. Abstract : Red‐emissive sulfur was synthesized through a two‐step oxidation strategy using elemental sulfur and Na2 S as starting materials. It possesses aggregation‐induced emission properties attributed to the presence of oxygen vacancies providing additional energy states in the red spectral region.