Two‐Step Oxidation Synthesis of Sulfur with a Red Aggregation‐Induced Emission

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 Na2S as starting materials, with a high photoluminescence quantum yield of 7.2 %. Polysulfide is formed first and is partially transformed into Na2S2O3 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 Na2S2O3 into Na2SO3 incorporated with oxygen vacancies, thus resulting in the formation of a solid‐state powder consisting of elemental S embedded in Na2SO3. 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.

49.25% efficient cyan emissive sulfur dots via a microwave-assisted route

“…1d (inset). Obviously, the emergence of the peak at around 330 nm is the key factor related to enhanced PL emission, 22 although the origin of this band is still an open question.…”

Efficient Conversion of Elemental Sulfur to Robust Ultrabright Fluorescent Sulfur Quantum Dots Using Sulfur-Ethylenediamine Precursor

“…Elemental sulfur (S), one of the main coproducts of the hydrodesulfurization reaction in the natural gas and petroleum refining industry, is abundant and cheap. , At present, the S has been widely used in sulfuric acid production, sulfur-rich polymers, chemical fertilizers, lithium–sulfur batteries, and other fields. − However, every year, there is still up to 8 million tons of surplus S because the consumption of S is far lower than its production . Meanwhile, hoarding such a large amount of surplus S is risk due to its high reactivity.…”

Ratiometric Fluorescence Assay for Pyrophosphate Based on Sulfur Nanodots Decorated Metal‐Organic Frameworks

“…The intensive peaks at 167.5, 168.6, and 169.7 eV suggest the presence of SO 3 2− and SO 4 2− [16] . The broad peak between 162 and 164 eV confirms the presence of elemental sulfur, and the peak at 161.4 eV suggests the absorption of divalent sulfur ions on the surface of S‐dots [17] . The FTIR spectra of pure PEG and S‐dots also show identical peaks (Figure 2c), located at 2873 cm −1 , 1455 cm −1 , 948 cm −1 , corresponding to the stretching vibration of C−H, the bending vibration of C−H and the stretching vibration of O−H, respectively [18] …”