Dimeric properties of Rhodamine B in glycerol, ethylene glycol, and acetic acid

Abstract

Publication costs assisted by Keio University Absorption spectra of rhodamine B are examined in solutions of glycerol, ethylene glycol, and acetic acid. Particular attention is given to the absorption spectra of monomers and dimers of rhodamine B in these solutions. Furthermore, dimeric structures of rhodamine B in these solutions are also investigated.

Characterization and photocatalytic activity of ZnSe nanoparticles synthesized by a facile solvothermal method, and the effects of different solvents on these properties

“…In order to investigate the photocatalytic activity of the ZnSe nanoparticles, RhB is chosen as the photocatalytic degradation dye since it is a good model compound as a target pollutant that is stable under UV irradiation [36]. Prior to the photocatalytic reaction, the RhB solutions are first photolyzed in the absence of the photocatalysts to determine their stability.…”

Supramolecular architecture, spectroscopic properties and stability of C.I. Basic Violet 10 (Rhodamine B) at high concentration

“…It is well known that dye molecules tend to form supramolecular architectures via self-assembly in solution or in adsorbed states [8][9][10][11][12][13][14][15]. For example, Tian et al [3,16] fabricated lowdimensional nanorods and nanospheres of a stilbazolium-like organic dye with highly monodisperse size using a self-assembly method.…”

Off/On Fluorescent Nanoparticles for Tunable High‐Temperature Threshold Sensing

“…This form is stabilized in the presence of polar protic or chlorinated solvents such as those used in the present synthesis, whereas the colorless (λ max abs = 316 nm) and weakly fluorescent lactone form (Scheme S2, Supporting Information) is generally stabilized in nonpolar solvents (e.g., cyclohexane) . Worth to mention though, the Vis absorption band at (λ max = 557 nm) is shifted by comparison with the one obtained for a bulk solution measurement (λ max abs = 545 nm) pointing out already to solvatochromism and the formation of aggregates within the nanoparticles. This aggregation was confirmed by fluorescence spectra (Figure b), which exhibits a very weak and broad band at λ max = 610 nm (≈40 nm red‐shifted with respect to the corresponding measurement in an organic solution).…”

“…The pink and highly fluorescent (λ max emi = 595 nm) solution obtained by dissolving the RhB‐base in liquid DA ( T > T m DA , 47 × 10 −6 m ) was in agreement with the formation mostly of the RhB‐zw form (Figure S5, Supporting Information). The lack of any fluorescence enhancement upon addition of glacial acetic acid (Figure S6, Supporting Information), which is described to boost the formation of the RhB‐zw form,[20,21a] confirmed that the formation of this species was almost quantitative already in liquid DA. At lower temperatures ( T < T m DA ), the solution solidified while maintaining the pink color characteristic of the RhB‐zw form.…”

“…This aggregation was confirmed by fluorescence spectra (Figure b), which exhibits a very weak and broad band at λ max = 610 nm (≈40 nm red‐shifted with respect to the corresponding measurement in an organic solution). The formation of mainly nonfluorescent H‐type aggregates of RhB within the NPs accounts for their very low fluorescence,[21a] while the residual emission was ascribed to the presence, in small amount, of the monomeric RhB species and/or J‐aggregates (in line with the red‐shift of the fluorescence spectra). For comparison purposes, we have also synthesized the same NPs but with a fivefold RhB concentration decrease (0.4 wt%), which favored: a) a narrower visible absorption band (λ max abs = 557 nm, Figure S1a, Supporting Information) with a less intense shoulder at 518 nm (in line with the decrease of nonfluorescent H‐aggregates)[15,21a] and b) the observation of an ≈7 times more intense band, narrower, and slightly blue‐shifted (λ max = 604 nm) fluorescence (Figure b; Figure S2, Supporting Information).…”