Polar Solvents Research Articles

Development of Donor-acceptor-type Molecules and Their Application as Analytical Reagents

π-Extended donor-acceptor (D-A)-type molecules, which bear both electron-donor and electron-acceptor substituents on the backbone, exhibit unique optical properties, such as bathochromic shifts in absorption and emission, large Stokes shifts, solvatochromic behavior, and fluorescence quenching in polar solvents. These unique properties are attributed to intramolecular charge transfer (ICT) or twisted intramolecular charge transfer (TICT) in the ground and excited states. This review article introduces three types of D-A-type molecules that are used as detection reagents for (1) methanol, (2) amino acids during solid-phase peptide synthesis (SPPS), and (3) amines present in the biological environment. For methanol detection, D-A-type fluorophores with basic guanidine moieties were developed to differentiate between methanol (MeOH) and ethanol (EtOH) based on the small difference in their pKa values (ΔpKa=0.4). Selective protonation of the guanidine moiety in methanol disrupts the D-A structure, allowing emission in the resultant polar environment. Similarly, an acid-base reaction between the hydrogen chloride (HCl) salts of the D-A-type molecules and amines is applied to detect amines during SPPS. In this method, a colorless solution of an HCl salt of the D-A-type molecule is deprotonated by amines, forming a yellow solution. This is the first reported quantitative and non-destructive colorimetric method for detecting amines. Finally, a turn-on-type amine-labeling reagent was developed for the nucleophilic aromatic substitution (SNAr) reaction. This new reagent enables protein staining of living cells with a large Stokes shift and without solvent-polarity-dependent fluorescence quenching.

Tailoring Light-Harvesting in Zn-Porphyrin and Carbon Fullerene based Donor-Acceptor Complex through Ethynyl-Extended Donor π-Conjugation.

Organic photovoltaic efficiency though currently limited for practical applications, can be improved by means of various molecular-level modifications. Herein the role of extended donor -conjugation through ethynyl-bridged meso-phenyl/pyridyl on the photoinduced charge-transfer kinetics is studied in noncovalently bound Zn-Porphyrin and carbon-fullerene based donor-acceptor complex using time-dependent optimally tuned range-separated hybrid combined with the kinetic rate theory in polar solvent. Noncovalent dispersive interaction is identified to primarily govern the complex stability. Ethynyl-extended -conjugation results in red-shifted donor-localized Q-band with substantially increased dipole oscillator strength and smaller exciton binding energy, suggesting greater light-harvesting efficiency. However, the low-lying charge-transfer state below to the Q-band is relatively less affected by the ethynyl-extended -conjugation, yielding reduced driving forces for the charge-transfer. Detailed kinetics analysis reveals similar order of charge-transfer rate constants (~1012 s-1) for all donor-acceptor composites studied. Importantly, enhanced light-absorption, smaller exciton binding energy and similar charge-transfer rates together with reduced charge-recombination make these complexes suitable for efficient photoinduced charge-separation. These findings will be helpful to molecularly design the advanced organic donor-acceptor blends for energy efficient photovoltaic applications.

Tuning the photophysical and NLO properties of β-diketonates derived from coumarin-triphenylamine-chalcones: effect of the BF2 group.

Herein the synthesis of three difluoroboron β-diketonate complexes (7a-c) and one chalcone (7d) with coumarin and triphenylamine fragments is described. The effect of the inclusion of the difluoroboron (BF2) group and a phenyl linker on the photophysical properties, intramolecular charge transfer (ICT) and nonlinear optical (NLO) properties was studied. These dyes exhibited excellent ICT properties due to their A-π-D and D-π-A-π-D type push-pull configuration. Thus, all compounds presented a strong solvatochromism, given the absorption and emission maxima shifted to red because of the increase in the polarity of the medium. In addition to this, 7a-d showed the formation of a twisted intramolecular charge transfer (TICT) state, which quenched fluorescence in polar solvents. Compounds 7a, 7b and 7d exhibited aggregation-induced emission (AIE) in MeCN/H2O mixtures, while 7c did not have this behavior. In addition, all compounds showed emission in the solid state. Using DFT and TD-DFT calculations, the molecular geometries of the ground state S0 and the first excited state S1 were elucidated, which confirmed the formation of a TICT state. Furthermore, the theoretical and experimental absorption electronic transitions were correlated by testing different functionals: B3LYP, CAM-B3LYP, PBE0, wB97XD, HSEH1PBE and M062X. Frontier molecular orbitals (FOMs) and molecular electrostatic potentials (MEPs) supported the ICT from the donor to the acceptor group. The global reactivity descriptors were studied and the NLO properties were predicted by calculating first (βtot) and second-order (γave) hyperpolarizabilities, revealing that 7a-d would present promising NLO behavior.

Effect of branching in the alkyl chain of diglycolamide on the sequestration of tetravalent actinides: solvent extraction and theoretical studies.

DGA (diglycolamide) ligands show a different extraction behavior of trivalent metal ions by changing the branching alkyl chain length as well as the branching at the methylene position. There are no studies of these factors on the extraction efficiency of these DGA derivatives for the extraction of tetravalent actinides. We have evaluated four different DGA derivatives for the extraction of Np, Pu, and Th from molecular diluents. The n-butyl derivative shows enhanced extraction efficiency and branching gives rise to a reduction in the extraction efficiency of tetravalent ions. The distribution ratios are higher in pure octanol than in a mixture of 30% octanol and 70% n-dodecane. This behavior is in marked difference to that of the extraction of trivalent ions where the addition of an alcohol generally decreases the distribution ratio of trivalent ions due to the ligand-modifier intercation, poor aggregation or micelle formation tendency of DGAs in polar solvents. This suggests that micelle-mediated extraction may not be the dominating factor for the extraction of tetravalent metal ions. Slope analysis suggests the involvement of only two DGA molecules in the extracted species suggesting no/poor possibility of micelle formation in the present system. The higher extraction in pure octanol may be due to a better solubility of the extracted complexes in this polar medium compared to the mixture of octanol and n-dodecane. The water and acid uptake, the back extraction, and the radiation stability of the solvent systems were also investigated. DFT studies were performed to get a better insight into the extraction and complexation of the different DGA solvent systems.

Versatile photoluminescence behavior of polycyclic hydroxybenzimidazoles driven by intermolecular hydrogen bonding

Herein, the synthesis of polycyclic hydroxybenzimidazole based on 4-hydroxyphthalimide is presented and two isomeric structures are formed. The isomeric structures are capable of forming intermolecular hydrogen-bonded molecular associates. Hydroxybenzimidazole hydrogen-bonded organic frameworks have been shown to be sensitive to different solvent polarity, particularly in proton donor media, resulting in a blue shift in emission. The role of proton donor media has been evaluated using the binary mixture of acetonitrile/water and protonation by trifluoroacetic acid. The results show that by tuning the environment, the aggregation induced emission has appeared in the blue region and larger aggregates are formed compared to the less polar aprotic solvents. Under acidic conditions, the disruption of the hydrogen-bonded dimers was estimated, resulting in deep blue emission. This provides an opportunity to control the molecular associates and tune the optical behavior.

TFE Terpolymers: Once Promising - Are There Still Perspectives in the 21st Century? Part II: Processing, Properties, Applications.

Tetrafluoroethylene (TFE) terpolymers have emerged as advantageous substitutes for polytetrafluoroethylene (PTFE). Therefore, they are being considered as alternatives to PTFE in many application areas. The advantages of TFE terpolymers include their facile processability at elevated temperatures, their solubility in some polar organic solvents, their inertness against aqueous acids, aqueous bases and a large number of mostly nonpolar organic solvents, their low dielectric constant, their low refractive index as well as useful electro- and thermochemical properties. This review on TFE terpolymers focuses on their processing including shaping and surface modification as well as on selected properties including wettability, dielectric properties, mechanical response behavior, chemical stability, and degradability. Applications including their use as elastomeric sealing material, liner and cladding layer as well as their use as material for membranes, microfluidic devices, photonics, photovoltaics, energy storage, energy harvesting, sensors, and nanothermitic composites will be discussed. The review concludes with a discussion of the future potential of TFE terpolymers and scientific challenges to be addressed by future research on TFE terpolymers.

Enhancing the anodic dissolution uniformity of dendritic-structured refractory high entropy alloys using a split electrolytic cell with a deep eutectic solvent

The attainment of uniform anodic dissolution in dendritic-structured refractory high entropy alloys (RHEAs) during the electropolishing process is essential for their utilization in high-precision components. Nevertheless, the intricate microstructures of these materials impede uniform dissolution, resulting in suboptimal surface quality. In this work, based on a choline chloride-based deep eutectic solvent and suitable polarization parameters selected by linear scanning voltammetry, a split electrolytic cell (SEC) was proposed to alter the traditional integrated electrolytic cell (IEC) to enhance the anodic dissolution uniformity of dendritic-structured RHEAs. A much smoother surface with Ra of 0.233 μm and a smaller height discrepancy of 0.8 μm was obtained, compared to those processed in IEC at the same condition. The non-uniform anodic dissolution was mainly attributed to the cathode-forming (hydroxide ion (OH−), dissolution of tungsten (W) in the dendrite region under the attack by OH−, and the formation of by-product, i.e., the water molecule. The positive impact of SEC on dissolution uniformity could be ascribed to its role in inhibiting OH− from interacting with the anode, as well as to the enhancement of solution acidity on the anode side, which facilitated the dissolution of metal oxides. The suggested reaction pathway was subsequently validated through experiments with controlled water concentration and assessing of electrochemical kinetics. Finally, the effects of SEC under different parameters were demonstrated. This work provides valuable insight into the precise, micro/nanoscale manufacturing and green electrochemical surface finishing of RHEAs in the future.

Temperature-Dependent Rotational Dynamics of a Polar Probe in Non-Polar Aprotic Solvents: Interplay of Solvent Viscosity and Size Effect.

Rotational dynamics of 3-(benzo[d]thiazol-2-yl)-7-(diethylamino)-2H-chromen-2-one (3BT7D2H-one) probe in non-polar aprotic 1,4 dioxane, toluene and cyclohexane solvents of different and comparable viscosity are studied with varying temperature using steady-state and fluorescence depolarization technique. The experimental reorientation time is compared with the hydrodynamic Stoke's-Einstein-Debye(SED). The experimentally measured rotational reorientation times are higher in 1,4 dioxane attributed to its solvent viscosity. In cyclohexane, the solute rotational dynamics behavior shows a transition from sub-slip to SED slip boundary conditions with varying temperatures. Solvent viscosity, size, and subtle changes in the molecular shape of solute play an important role in the rotational dynamics of polar probes in non-polar aprotic solvents.

Exploring the mechanisms of benzanilide crystal growth and morphology: Crystal surface structure, solvent diffusion and solvent-interface interactions

Flaky crystals are fragile, rendering them unsuitable for various applications including use, processing, storage and transportation. This work investigates the growth and morphology regulation mechanisms of flaky crystals using benzanilide as a model material. Initially, block-like crystals are prepared by solvent screening and cooling crystallization with its morphology greatly improved. Subsequently, growth kinetics of (111), (1–10) and (020) faces are established with crystal growth experiments. The crystal growth of (001) face is also determined to follow a two-dimensional nucleation model with the microscopic surface analysis using atomic force microscopy. The changes of the surface integration resistance and the growth step height are regarded as kinetic mechanisms of the growth behavior and crystal morphology modulation by solvent and supersaturation. Finally, the molecular mechanism of the modulation of the solvent in crystal morphology is revealed base on crystal surface structure analysis and molecular dynamics simulations. The weak solvent-interface polar interactions facilitate the incorporation of benzanilide molecules into the weak polarity (001) face, leading to the surface roughening and increased crystal thickness when employing strongly polar solvents such as acetonitrile. Unlike the former, the relatively weak hydrogen bonding interactions between solvents and strong polarity (020) face, and the higher diffusion ability of molecules promote the rapid growth and disappearance of (020) face in ethanol and acetonitrile with strong hydrogen bond formation ability. This study can contribute to a deeper understanding of the solvent effect on crystal morphology and provide guidance for optimizing crystallization conditions to obtain shape-tailored crystal products.

Regulating interfacial reactions via quasi-solid polymer electrolyte to enable high-voltage lithium metal batteries

Sulfolane (SUL), known for its low cost, environmental friendliness, and high voltage tolerance, stands out as a promising polar solvent for lithium (Li) metal batteries with high energy density. However, its long-term stability with Li metal is compromised due to its inherently low reduction resistance. To address this issue, we introduce a novel electrolyte strategy, where the reactive SUL is encapsulated within a fluorinated polymer framework formed through in-situ thermal polymerization. The polymer network’s specific structure interacts with SUL, effectively mitigating its electrochemical degradation on the Li metal anode and the NCM811 cathode, thus enhancing electrode stability. This approach not only extends the Li+ plating/stripping reversibility for over 1,000 h at a current density of 0.3 mA cm−2, but also delivers outstanding performance in NCM811||Li batteries, achieving a capacity retention of 78.56 % after 1,000 cycles at 30 °C and 87.14 % after 100 cycles at 60 °C under a high cutoff voltage of 4.5 V.

Synthesis, Characterization, and Interaction Studies of Naphtho‐[2,3]‐furan‐Based Molecules with CTAB as Model Surfactant

AbstractThe synthesis of highly sensitive UV–visible active naphthofuran derivatives, namely naphtho‐[2,3]‐furan‐3‐yl acetate (NF), 9‐bromonaphtho‐[2,3]‐furan‐3‐yl acetate (BNF), 9‐nitronaphtho‐[2,3]‐furan‐3‐yl acetate (NNF), 9‐iodonaphtho‐[2,3]‐furan‐3‐yl acetate (INF), and naphtho‐[2,1‐b]‐furan‐4‐carboxylic acid (ONF) as solvatochromic molecules, was carried out through multistep synthetic approach. These molecules possess different substituents that tend to form micelles in cetyl trimethylammonium bromide (CTAB) aqueous system. During the micellization process, the absorption spectrum of the synthesized molecule exhibits sensitivity towards the polarity of the environment, which affects the critical micelle concentration (cmc) of CTAB. This study demonstrates that synthesized molecules can be used for estimating solvent polarity and cmc.

Solvatochromism, preferential solvation and excited state dipole moments of flufenamic acid in different solvent polarities

The influence of pure solvent and binary solvent mixtures on the optical properties of non-steroidal anti-inflammatory drug (NSAID) molecule, specifically flufenamic acid (FLA), has been studied using absorption and fluorescence spectroscopic techniques. A bathochromic shift is observed in the emission wavelength of FLA with an increase in the solvent polarity of pure solvents, attributed to the highest stability of the excited state. The spectral properties are correlated with Lippert–Mataga, solvent polarity parameter, Kamlet, and Catalan solvent polarity parameters, suggesting that both general and specific solvent effects influence the spectral properties, with general solvent effects dominating over specific solvent effects. Preferential solvation studies have been carried out in tetrahydrofuran (THF) and water solvent mixture, revealing variations in the preference for solvation of FLA as a function of the mole fraction of water. Solvatochromic data are utilized to estimate the excited state dipole moment in pure solvents using different solvatochromic methods, revealing that the excited state dipole moment of FLA is higher than its ground state counterpart. The increase in dipole moment in the excited state compared to the ground state is explained based on intramolecular charge transfer (ICT), with elaboration and discussion on the possible resonance structure corresponding to ICT, inferring the more polar nature of the excited state compared to the ground state. The effect of solute polarizability on the excited state dipole moment and change in dipole moment is also discussed.

Upgrading Biomass Wastes to Graphene Quantum Dots with White-Light-Emitting Features in the Solid State

The emergence of bio-based carbonaceous materials for various applications has attracted significant attention during the last few years. Here, we report a rapid, efficient, and reproducible microwave-assisted synthesis of graphene quantum dots (GQDs) with identical features irrespective of the nature of biomass waste investigated. The synthesized GQDs were fully characterized by X-ray photoelectron spectroscopy, Fourier-transform infrared spectroscopy, transmission electron microscopy, and dynamic light scattering. The nanoparticles displayed narrow sizes of 1–2 nm and high solubility in polar solvents such as water and ethanol. The protocol described herein is advantageous in comparison to dealing with the synthesis of GQDs from biomass waste previously reported since our protocol is faster owing to the use of microwave heating and the avoidance of dialysis for the purification step. Furthermore, in solution, the water-soluble particles showed excitation-dependent photoluminescence ranging from blue to orange emission wavelengths. Interestingly, thin films displayed white-light emission under 325 nm UV-light excitation, while aggregation-induced quenching was usually observed, opening the way for their potential use as a phosphor in white-light-emitting diodes.

Screening of Antibacterial and Antifungal Activities of Basidiomycetes Extracts

Background. Basidiomycetes have high biosynthetic capabilities. Their metabolites are capable of exhibiting antimicrobial properties, thereby being promising molecules for use in medicine or for further chemical transformation. The aim of the work. Evaluation of antibacterial and antifungal properties of culture liquid of basidiomycetes from the orders Agaricales and Polyporales, selection of active strains for further research. Materials and methods. The objects of the study were 10 strains of 10 basidiomycetes species from the orders Agaricales and Polyporales. Filtrates of culture liquids obtained as a result of submerged cultivation of fungi, their ethyl acetate extracts and post-extraction liquids were tested. The culture liquid of Fomitopsis betulina was also extracted with chloroform and butanol. Antibacterial and antifungal effects were studied by diffusion from wells into agar. Results. All the studied strains of basidiomycetes showed antibacterial activity. The highest activity against gram-positive and gram-negative bacteria was observed in strains of 3 species from the order Polyporales: Fomes fomentarius, F. betulina and F. pinicola. Antifungal activity was shown by 6 out of 10 studied cultures of basidiomycetes. The comparative series of extractants compiled by their effectiveness (ethyl acetate > butanol > chloroform) testified to the advantage of using polar solvents to extract antimicrobial metabolites of F. betulina from the its culture liquid. Conclusion. Three promising strains of basidiomycetes — producers of antimicrobial metabolites were selected.Among the studied species, representatives of the order Polyporales showed the greatest activity. Polar solvents extracted antimicrobial metabolites of F. betulina from its culture liquid more efficiently than non-polar chloroform. The obtained results demonstrate the ability of basidiomycetes to produce metabolites with antimicrobial properties. It is noted that species of the order Polyporales are more active than representatives of Agaricales.

Self-Assembled Ultra-Long Hybrid Nanowire Formed by Simple Mixing: An Untapped Feature of Peroxydisulfate.

Peroxydisulfate (PDS), a popular molecule that is able to oxidize organic compounds, is garnering attention across various disciplines of chemistry, materials, pharmaceuticals, environmental remediation, and sustainability. Methylene blue (MB) is a model pollutant that can be readily oxidized by PDS-derived radicals. Unlike the conventional degradation process, here a reversible "dissolution-precipitation" phenomenon is discovered, triggered by a simple mixing of PDS and MB, revealing a novel application of PDS in fabricating self-assembled ultra-long nanowires with MB. This phenomenon is unique to PDS and MB, different from the traditional salting out or self-aggregation of dyes. Formation of nanowires facilitated by electrostatic interaction between S+ and O- moieties and π-π stacking is reversible, controlled by temperature and the solvent polarity. MB1-PDS-MB2 configuration (MB: PDS = 2:1) is theoretically predicted by density functional theory (DFT) calculations and further validated by stoichiometric ratios of carbon, sulfur, and nitrogen in the obtained precipitates (MBO). This untapped feature of PDS enables the development of colorimetric quantitative detection of PDS and sustainable dye recycling. Far more than those demonstrated cases, the potentialities of MBO as a nanomaterial merit further exploration.

Morphology Regulation of Organophosphate Crystals by Micro‐Jetting Technique

AbstractOrganophosphates nucleating agents are widely used in the plastics industry. Nucleating agents with different morphologies have various effects on the resin materials. The micro‐jetting technique is shown to be a promising tool for the controlled preparation of micro‐and nano‐sized particles. Therefore, in this paper, controllable preparation of sodium 2,2'‐methylene‐bis‐(4,6‐di‐tert‐butylphenyl) phosphate (NA11) is achieved by the micro‐jetting technique. The study focused on the impact of various parameters on its shape and size. Hexagonal, rhombic, rod‐shaped, and needle‐shaped micro‐sized NA11 crystals are prepared. The results show that the decrease in the polarity of the organic solvents added in the antisolvent water led to the transformation of NA11 from bulk hexagon to plate‐like rhombus and finally to needle‐shaped crystals. The addition of surfactants can regulate the crystal growth rates and orientations, thereby facilitating the formation of rod‐shaped crystals. Based on rod‐shaped crystals, the crystal size is studied. Crystals with average particle sizes in the range of 40–100 µm can be obtained with coefficients of variation as low as 4% by varying the relevant experimental parameters such as the supersaturation, the solution homogeneity in the crystal growth environment, and the mixing intensity. This study provides references for designing functional materials.

Water‐Soluble, Spin‐Cast‐Based Crystalline Poly(Methacrylic Acid) Film as a Reversible Li‐Ion Battery Anode

Poly(methyl methacrylate) (PMMA) polymer anodes are proposed as potential reversible anode materials for lithium‐ion batteries (LIBs) owing to their simple thin‐film formation process and cost‐effectiveness. Nevertheless, challenges such as the use of toxic aprotic solvents and the irreversible consumption of Li ions during the initial cycle need to be addressed to improve their performance. Herein, a water‐soluble poly(methacrylic acid) (PMAA) polymer processed using a simple spin‐casting method as a reversible LIB anode is presented. Unlike the PMMA anode, the conjugated carbonyl groups of the crystalline PMAA polymer readily form a chain backbone during ex situ thermal annealing, demonstrating a reversible capacity. The mechanism underlying the superior electrochemical characteristics of the PMAA anode is revealed using grazing incidence X‐ray diffraction and theoretical calculations. In particular, the highly crystalline cyclic anhydride PMAA polymer induced by thermal annealing shows enhanced interactions between Li ions and CO groups during operation, resulting in improved electrochemical properties. The resulting crystalline cyclic anhydride PMAA anode achieves a capacity of ≈427.7 mAh g−1 and retains a reversible specific capacity of 156 mAh g−1 after 500 cycles, indicating that it is a promising polymeric anode for next‐generation LIBs.

Effects of Pleurotus Eryngii (DC.) Quél. Mushroom Extracts on Cell Proliferation in Breast and Colon Cancer Cell Lines

This study was aimed to collect Pleurotus eryngii (DC.) Quél. edible/medicinal mushroom from Çanakkale/Kumkale and to evaluate the antiproliferative effects of alcoholic extracts on breast and colon cancer cell lines. For this purpose, the Soxhlet method prepared methanol and ethanol:H2O (70:30) extracts by gradually increasing solvent polarities. Then, breast (MDA-MB-231, BT-549, BT-20, MCF-7) and colon (HT-29) cancer cell lines were treated with the extracts in increasing concentrations (0.05-0.5 mg/mL) for 48 h. In conclusion, methanol and aqueous ethanol extracts exhibited significant antiproliferative effects in cancer cell lines, according to the MTT assay. The cell viability in the triple-negative breast cancer (TNBC) MDA-MB-231 cell line was highly decreased by methanol extract at a very low concentration (0.1 mg/mL). Furthermore, methanol extract at 0.3 mg/mL reduced the percentage of cell viability in the HT-29 cell line. Aqueous ethanol extract showed antiproliferative activity in breast and colon cancer cell lines at 0.25 mg/mL concentration for 48 h applications. In addition, some bioactive components such as 4-hydroxy flavone, chrysin, and tannic acid of aqueous ethanol extract have been determined by High-Performance Liquid Chromatography (HPLC) analysis. As a result, this study may increase interest in the studies on the anti-cancer activities and the mechanisms of P. eryngii mushroom.

Solubility Study of a Ladder-Like Polyphenylsilsesquioxane for Membrane Application

In this work, the solubility of a high-molecular-weight homopolymer, a ladder polyphenylsilsesquioxane, was studied in different classes of solvents, including alcohols, aprotic solvents, ketones, alkanes, and aromatic hydrocarbons. The Hansen parameters and the parameter of long-range interaction between the polymer and the solvent were analyzed. The insolubility of L-PPSQ in a wide range of solvents allows for expecting that the properties of a membrane on its basis would be stable during operation in these media. At the same time, aprotic solvents are well suited for the preparation of membranes based on L-PPSQ by the solution phase inversion method.

Harvesting the tuning mechanism of strategic polychrome and white light emission in NapH dye based on excited state intermolecular proton transfer

Organic white light emitting (WLE) materials have sparked a research boom due to their promising applications in display devices, artificial lighting, and molecular sensors. However, the complex luminescence mechanism of full-spectra emitting materials has limited the development of white light materials with high stability and reproducibility. In this study, building on the full-spectra luminescent naphthimide dye (NapH) introduced by Xu et al., (Chin. Chem. Lett. 35(2024), 108348), we report the solvent-sensitive excited state proton transfer (ESPT) properties and white light emission mechanism in NapH. Our theoretical research results show that the ESPT process of NapH molecule is hindered in the low-polar solvent tetrahydrofuran (THF), so only the blue fluorescence from the Enol* is observed in the experiment. In contrast, in polar solvents such as water (H2O) and methanol (MeOH), the formation of strong intermolecular hydrogen bonds successfully initiates the ESPT process, leading to the dual fluorescence observed in experiments, with blue emission from the Enol* and red emission from the Nap anion. In essence, different solvent environments can adjust several emission colors. Furthermore, we theoretically verify that the optimal white light emission can be achieved when the mixed solvent ratio of dimethyl sulfoxide (DMSO) and dioxane (DIOX) is 5:5, which aligns well with experimental results. More importantly, we elucidate the specific WLE mechanism from multiple perspectives, including potential energy curves and electron spectra. Our work not only displays the interaction models of NapH molecule in various solvents, but also reveals the underlying luminescence mechanism, thus providing a valuable theoretical reference for the development and advancement of new white light materials.