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Indium-based quantum dots (QDs), such as copper indium disulfide and zinc copper indium sulfide, have been the center of research for decades due to their low toxicity and unique photophysical properties. In contrast, versatile indium-based materials like In₂S₃ and ZnIn₂S₄ have been rarely studied in their QD form because of the challenges in their synthesis and used in solid-state material based applications because of their colloidal nature. In this study, a one-pot single-step method to synthesize In₂S₃, ZnIn₂S₄, and Cu-doped ZnIn₂S₄ QDs trapped in insoluble solid-state oleic acid matrices was developed. The QDs in solid-state matrices exhibited bright orange colored fluorescence with controllable emission properties achieved by altering the chemical composition. Among these QDs, the ZnIn₂S₄ QDs displayed thermo-responsive properties. As the temperature increased, the fluorescence intensity of ZnIn₂S₄ QDs decreased. In addition, all QDs demonstrated high removal efficiency for micropollutants in the aqueous medium, especially against cationic organic dyes. This study represents one of the first attempts at the direct development of QDs trapped in insoluble solid-state matrices. The QDs in solid-state matrices hold promise for applications in thermal sensors and studies related to the micropollutant removal.

A size-controllable fluorescent ZIF-8 structure is synthesized through modification with a versatile supramolecule, bis-carboxylate functional calix[4]pyrrole. Upon modification, the micropollutant removal properties of ZIF-8 were adjustable.

Cadmium-based quantum dots (QDs) are amongst the most studied nanomaterials due to their excellent photophysical properties, which can be controlled by controlling the size and/or composition of the nanocrystal. However, the ultraprecise control over size and photophysical properties of Cd-based quantum dots and developing user-friendly techniques to synthesize amino acid-functionalized cadmium-based QDs are still the on-going challenges. In this study, we modified a traditional two-phase synthesis method to synthesize cadmium telluride sulfide (CdTeS) QDs. CdTeS QDs were grown with an extremely slow growth-rate (growth saturation of about 3 days), which allowed us to have an ultraprecise control over size, and as a consequence, the photophysical properties. Also, the composition of CdTeS could be controlled by controlling the precursor ratios. The CdTeS QDs were successfully functionalized with a water-soluble amino acid, L-cysteine, and an amino acid derivative, N-acetyl-L-cysteine. Red-emissive L-cysteine-functionalized CdTeS QDs interacted with yellow-emissive carbon dots. The fluorescence intensity of carbon dots increased upon interaction with CdTeS QDs. This study proposes a mild method that allows to grow QDs with an ultraprecise control over the photophysical properties and shows the implementation of Cd-based QDs to enhance the fluorescence intensity of different fluorophores with fluorescence wavelength at higher energy bands.

Carbon dots (CDs) are versatile fluorescent nanocrystals with unique optical and structural properties and are commonly used in biosensing, bioimaging, and biomolecule tagging studies. However, fluorescence of CDs is brightest in the wavelength range of 430-530 nm, which overlaps with the autofluorescence range of many eukaryotic cells and makes CDs impractical for in vivo and in vitro imaging studies. Thus, the design of yellow-red emissive CDs with high quantum yield is of importance. In this study, the quantum yield of traditional yellow emissive CDs was enhanced by two different methods: (1) the surface of traditional yellow emissive CDs passivated with a biomolecule, urea, through easy, rapid, inexpensive microwave assisted synthesis methods and (2) a fluorescent biomolecule, aflatoxin B1, used as an energy donor for yellow emissive CDs. In the first method, the quantum yield of the CDs was enhanced to 51%. In the second method, an efficient energy transfer (above 40%) from aflatoxin B1 to the CDs was observed. Our study showed that highly luminescent yellow emissive CDs can be synthesized by simple, rapid microwave assisted synthesis methods, and these CDs are potential candidates to sense aflatoxin B1. Furthermore, our results indicated that Aflatoxin B1 can be considered as an emission booster for CDs.

Two new compounds, BODIPY–tetraphenylethylene dyad and BODIPY–o-carborane–tetraphenylethylene triad, were designed and synthesized. This molecular dyad and triad have been characterized by using various spectroscopic methods, including FT-IR, mass, UV-visible absorption and fluorescence emission spectroscopy, and one and two-dimensional homo- and hetero-correlated NMR spectroscopy. Photophysical properties, as well as solvatochromic and aggregation-induced emission (AIE) behavior, have been investigated. Single-crystal X-ray diffraction analysis has unambiguously revealed their structure and provides an explanation for the absence of AIE character. The redox properties showed that an o-carborane addition increased the reduction potential and shifted the oxidation potential to the positive site.