Emission In Solvents Research Articles

Intermolecular C–H⋯O hydrogen bond–induced H-aggregates for rapid, real-time detection of cyanide

A specialized chemodosimeter, H1, incorporates a solid red fluorophore formed using a nearly planar dimethylaniline–indanedione conjugate, leveraging an intramolecular charge transfer (ICT) mechanism engineered for cyanide detection. Chemodosimeter H1 exhibits strong ICT-induced emission in polar organic solvents, although its fluorescence diminishes in the solid state. Compared with the J-aggregated solid red fluorophore J1, which has a similar dimethylaniline–indanedione conjugate structure, chemodosimeter H1, with an extended vinyl conjugation, displays a relatively weak and blue-shifted red emission in the solid state because of formation of H-aggregates induced by intermolecular C–H⋯O hydrogen bonds. Binding between cyanide and chemodosimeter H1 results in color and emission changes for the latter, resulting in formation of a highly twisted structure, denoted as H1–CN, which subsequently impedes ICT. Furthermore, test strips employing the H-aggregated red fluorophore H1 present a promising approach for quantitative and rapid detection of cyanide (CN−). These results provide a new approach to designing solid red fluorophores based on H-aggregation for CN− detection.

Zero-dimensional hybrid Cu(I) halide with cyan light emission for use in white light emitting diode

Traditional white light-emitting diode (WLED) is mainly depending on coating broadband yellow phosphors (520–700 nm) on blue emitting LED chip (440–460). However, too strong blue light and absence of cyan light results in incongruous emission strength and low color rendering index (CRI), which cause serious damage to retina of eye. To overcome these shortcomings, cyan light emitting phosphor is highly desirable for the full-visible-spectrum LED with high CRI, but bright cyan phosphor remains rare. Herein, a new 0D hybrid copper(I) halide of [TMPDA]Cu2I6 (TMPDA = N,N,2,2-tetramethyl-1,3-propylenediamine) single crystal is reported as a cyan light emitter with mominant emission wavelength at 489 nm, photoluminescence quantum yield of 26.66 % and large Stokes shift of 198 nm exceeding most of organic-inorganic metal halides. Remarkably, the single crystals display stable emission in various polar organic solvents and high temperature with sufficient emitting stability. More significantly, this 0D cuprous halide act as down-conversion cyan phosphor to fabricate WLED with a high CRI of 95 by reducing the cyan gap. In this study, we demonstrate an optical engineering strategy to prepare efficient cyan light emitting 0D cuprous halide and assembly high-performance WLED.

Discovery of a novel marine bacterial AIEgen that lights up specific G-quadruplexes

The emergence of aggregation-induced emission (AIE) phenomenon two decades ago marked a significant advancement in chemical science. It has fostered the development of versatile AIE luminogens (AIEgens) applicable in bioimaging, optoelectronics, and biochemical sensing. However, the application potential of synthetic AIEgens is limited owing to their constrained chemical space, environmental concerns, and uncertain biocompatibility. Consequently, the pursuit of naturally derived AIEgens (BioAIEgens) is considered a promising solution to developing next-generation AIEgens. Here, we report the discovery of 2-(2-hydroxy-6-methoxy-3-propionylphenyl)quinazolin-4(3H)-one (HMPQ) from marine bacterial metabolite as AIEgen for the first time. HMPQ shows its unique fluorescence mechanism through excited-state intramolecular proton transfer. Comprehensive photophysical assessments unveiled that HMPQ varied emissions in diverse solvents and solid-state polymorphic forms. Notably, HMPQ exhibited specific binding affinity to G-quadruplexes (G4s), illuminating these non-canonical nucleic acid structures without altering their conformation. Its remarkable safety profile and precise cellular visualization of G4 structures imply HMPQ’s potential in biological applications, opening new avenues for utilizing BioAIEgens as G4 probes.

Fine-tuning the photophysical properties of Imidazo[1,2-a]pyridine-based dyes by the change in substituent and solvent media: DFT and TD-DFT studies

In the present work, photophysical properties of the nine excited-state intramolecular proton transfer (ESIPT) active 2-(2 -hydroxyphenyl)imidazo[1,2-a]pyridine (HPIP)-based dyes A1-A9 (X= H, Me, F, Cl, OMe, OH, CN, NO2 and CF3) were investigated at PBE0/6-31++G(d,p) and M06-2X/6-31++G(d,p) levels of theory in the gas phase and solvent media. The structural parameters, relative energies, vibrational spectra, photophysical properties, potential energy curves, natural bond orbital (NBO) charges, hole and electron isosurfaces, electron density properties and reduced density gradient (RDG) spikes were computed. The H-bonding is strengthened at the S1 state by comparing infrared vibrational spectra, the relevant bond length and bond angle, electron density properties and RDG analysis. The results revealed that ESIPT in the A1-A7 and A9 in the gas phase is a barrier-less process, while there is an energy barrier for the A8 (X=NO2). In polar solvents, it is predicted that the ESIPT process only in A5 and A6 is a barrier-less process. The A2, A4 and A5 exhibited the greatest redshift in the keto fluorescence emission in tetrahydrofuran solvents. The significant Stokes shift observed in the S1-K emission of certain dyes makes these molecules highly appealing for various applications such as chemosensors, fluorescent probes, laser dyes and optoelectronic devices.

Study of UV-cured tung oil-based polyalcohol resin with isophorone diisocyanate as crosslinker

Petroleum-based resins are associated with increasing energy demands and biodegradability issues. Resins produced from biomass raw materials are a suitable alternative and hold significant potential across various applications, including the manufacture of molding materials, oil-based resins, and adhesives. Particularly in the field of coatings, biomass-based resins are recognized for their environmental friendliness and renewability, although there remains room for improvement in terms of strength and curing speed compared with petroleum-based resins. In this study, we developed a high-strength tung oil-based polyurethane photocurable resin (TOPP). To produce the resin, tung oil was first converted into tung oil polyol, and then acrylic ester along with isophorone diisocyanate was used as a bridging agent to confer photocuring properties. Analysis via infrared and nuclear magnetic resonance spectroscopy confirmed the TOPP structure and demonstrated the reaction of carbon–carbon double bonds to form polyol. TOPP exhibited impressive mechanical properties, including a tensile strength of 21.02 MPa and an elastic modulus of 954.63 MPa, achieved through the optimization of the amount of hydroxyethyl methacrylate added. Additionally, TOPP exhibited excellent hydrophobicity with a maximum water contact angle of 88.78° and a low thermal conductivity of 0.26 W·(mK)−1. As a wood coating, TOPP significantly enhanced resistance to oil and improved waterproof performance. The curing speed was notably accelerated without emissions of volatile solvents, which demonstrates the substantial potential of the resin for coating applications on wooden products, particularly in the furniture industry.

Biomass-derived multiatom-doped carbon dots for water sensing based on excited state intraparticle proton transfer in organic solvents

The presence of trace water impurities in organic solvents can significantly influence chemical reactions and product quality; thus, the accurate detection of water content in these solvents is a critical requirement for industrial applications. Accordingly, an eco-friendly, effective, and economical sensor for detecting trace quantities of miscible water in organic solvents is required for industrial applications. In this study, we synthesized biomass-derived multi-atom-doped carbon dots (MACDs) as fluorescent probes and employed them for the detection of trace amounts of water impurities in several water-miscible organic solvents. The MACDs exhibited stable dual-color fluorescence emission under ultraviolet light irradiation and red and blue emissions in organic solvents and water. The fluorescence quantum yield was approximately 11 %, which indicates an excited intraparticle proton transfer response due to an increase in the water content within a wide response range from 0 % to 100 % (v/v) in organic solvents. The intensity of the red emission signal at 670 nm gradually decreased with an increase in the water content in the organic solvent. The MACDs could detect water with an instant response time of 55 s, a high sensitivity, and low limits of detection of 0.08 %, 1.36 %, 0.03 %, 0.04 %, 0.12 %, and 0.05 % (v/v) in ethanol, acetonitrile, dimethylformamide, methanol, isopropanol, and tetrahydrofuran, respectively. Hence, biomass-derived MACDs can serve as efficient and eco-friendly water sensors in organic solvents.

Fluorescence Sensing Properties of a Bibranched Cyanostilbene Derivative Containing -NH2 for Trace Water and Picric Acid Determination.

In order to design organic small molecule fluorescent materials with multiple sensing, a bibranched -NH2 modified cyanostilbene derivative (AM) was synthesized. It exhibits solvent and aggregation-induced emission effects, with a solid-state quantum yield of 28%, which is seven times higher than that in THF. The synthesized sample AM demonstrated high sensitivity to trace water via a fluorescence "turn-off" response, achieving a low detection limit of 0.41 µM in THF and 0.80 µM in EtOH. AM also exhibits a "turn-off" response to picric acid, attributed to the photo-induced electron transfer effect it induces. The recognition of picric acid by AM demonstrates specificity and resistance to interference from nitro explosives, with a detection limit of 300 ppb and a linear relationship (R2 = 0.9981) at the range of 0-4 equivalents AM. Such acid recognition can facilitate the design of qualitative test papers and safety inks. Additionally, AM can function as a temperature sensor with a linear relationship (R2 = 0.9976) within the temperature range of 25-110°C. Leveraging these unique characteristics, a series of methods were proposed for the direct quantitative determination of trace water in nonaqueous solvents, picric acid, and temperature.

Excited Charge Separation in a π-Interacting Phenothiazine-Zinc Porphyrin-Fullerene Donor-Acceptor Conjugate.

We have designed, synthesized, and characterized a donor-acceptor triad, SPS-PPY-C60, that consists of a π-interacting phenothiazine-linked porphyrin as a donor and sensitizer and fullerene as an acceptor to seek charge separation upon photoexcitation. The optical absorption spectrum revealed red-shifted Soret and Q-bands of porphyrin due to charge transfer-type interactions involving the two ethynyl bridges carrying electron-rich and electron-poor substituents. The redox properties suggested that the phenothiazine-porphyrin part of the molecule is easier to oxidize and the fullerene part is easier to reduce. DFT calculations supported the redox properties wherein the electron density of the highest molecular orbital (HOMO) was distributed over the donor phenothiazine-porphyrin entity while the lowest unoccupied molecular orbital (LUMO) was distributed over the fullerene acceptor. TD-DFT studies suggested the involvement of both the S2 and S1 states in the charge transfer process. The steady-state emission spectrum, when excited either at porphyrin Soret or visible band absorption maxima, revealed quenched emission both in nonpolar and polar solvents, suggesting the occurrence of excited state events. Finally, femtosecond transient absorption spectral studies were performed to witness the charge separation by utilizing solvents of different polarities. The transient data was further analyzed by GloTarAn by fitting the data with appropriate models to describe photochemical events. From this, the average lifetime of the charge-separated state calculated was found to be 169 ps in benzonitrile, 319 ps in dichlorobenzene, 1.7 ns in toluene for Soret band excitation, and ∼320 ps for Q-band excitation in benzonitrile.

Coumarin Derivative and Gold Nanoparticle Conjugate as a Selective Fluorescent Sensor for Mercury Ion in Real Sample.

A biphenyl based coumarin fluorescent molecule, N,N'-bis(7-diethylamino-2-oxo-2H-chromen-3-yl)methylene)biphenyl-2-2'-dicarbohydrazide (molecule 1) has been synthesized and characterised. Photophysical studies of 1 exhibit solvent polarity dependent absorption and emission maxima. Citrate capped gold nanoparticles (AuNPs) have been mixed with molecule 1 for the preparation of AuNPs/1 conjugate. The association constant of the AuNPs/1 conjugate has been calculated to 4.54 × 104 M- 1. The AuNPs/1 conjugate has been found to detect Hg2+ ion selectively by fluorescence enhancement. While addition of molecule 1 into the solution of AuNPs, fluorescence intensity of 1 quenched. On addition of several monovalent, divalent and trivalent metal ion into the solution of AuNPs/1 conjugate separately, there was no change in fluorescence intensity of 1 has been observed. However, upon addition of Hg2+ ion into the solution of AuNPs/1 conjugate, the fluorescence intensity enhancement occurred, indicating released of 1 from the surface of AuNPs and probably aggregation of AuNPs took place in presence of Hg2+ ion. The AuNPs/1 conjugate has been found to have a detection limit of 2.3 × 10- 9 M for Hg2+ ion in aqueous solvent. Meanwhile, the AuNPs/1 conjugate have also been successfully applied for the determination of Hg2+ in real water samples.

Synthesis, Physicochemical and Third Order Nonlinear Optical Properties of Bis-Chalcone (BBDP) as Donor-pi Acceptor Chromophore in Organize Medium.

Bis-Chalcone (BBDP) has been prepared by condensation of N, N-dimethyl benzaldehyde and 1,1'-([1,1'-biphenyl]-4,4'-diyl) di (ethan-1-one), and structure of BBDP was characterized by Mass Spectra, 13C-NMR, 1H-NMR, and IR. Physicochemical properties including Dipole-moments, Stoke-Shifts, Oscillator-strength, dielectric constant and quantum-yields of fluorescence of BBDP were investigated by the emission and absorbances in different solvents. Compound (BBDP) displayed bathochromic shift upon increasing the solvent polarity (from n-Hexane to DMSO). Furthermore, we have exploited third-order nonlinear optical characteristics of the bisChalone were invigilated by the Z-scan techniques in Chloroform. The measurements were taken with a continuous-wave (CW) diode laser having a wavelength of 520 nm in CHCl3 solvent. The third-order nonlinear optical properties, such as the nonlinear refractive index (NLRI) n2, nonlinear absorption coefficient (NLAC) β, and nonlinear susceptibility χ(3), were measured at various solution concentrations and laser powers. The obtained values of n2, β, and χ(3) were estimated to be high, of the order of 10-7(cm2/W), 10-3 (cm/W), and 10-6 (esu), respectively. As a result, bis-chalcone (BBDP) is considered as a promising candidate for applications in nonlinear optical (NLO) devices and optical limiting (OL).

Pd-Catalysed Direct Arylation of Distyrylbenzene: Strong Dual-state Fluorescence and Electrochromism.

Distyrylbenzenes (DSBs) are well-known for their strong multicolour fluorescence. Fluorescence tuning of DSB via further functionalization/arylation, on the other hand, is uncommon. This paper reports a Pd-catalysed direct arylation approach for introducing different aryl groups onto fluorobenzene-containing DSB moiety (7) in high yields (67-72 %). The versatile methodology allows the substitution of neutral [tolyl (1)], electron-deficient [p-formyl benzene (2), p-acetyl benzene (3), p-nitrobenzene (4)] and electron-rich [carbazole (5), triphenylamine (6)] aryl groups. The electron-deficient aryls render mono-substitution, while the electron-rich counterparts promote di-substitution. The compounds (1-6) show blue, green, and yellow fluorescence in both the solution and solid states; the fluorescence quantum yields reach >98 % and the peak maxima span from 425 to 560 nm. The mono-carbazole DSB (5) exhibit white light emission (WLM) in polar solvents (acetone, DMF, CH3CN, DMSO and NMP) with very high fluorescence quantum yields (φf) of 60-80 %. For WLM, such high efficiency (φf) is somewhat uncommon. Moreover, visible-to-NIR reversible electrochromism is demonstrated by the TPA-integrated DSB (6). The colour of 6 changes from pristine light yellow to orange, and the absorption maxima shifts from 372 to 1500 nm when a positive potential of 1.0 V vs Ag/Ag+ is applied. Moreover, the system shows high colouration efficiency in the NIR region with fast switching speeds for colouration and decolouration as fast as 0.98 s and 1.05 s.

Triple B←N Lewis Pair-Functionalized Triazatruxenes with Large Stokes Shifts.

A novel class of multiple B←N Lewis pair-functionalized polycyclic aromatic hydrocarbons with different BR2 groups (R = Cl or Et) directly attached at positions 1, 6, and 11 of triazatruxene was synthesized. The triazatruxene backbone of 4 displays a bowl shape, and its molecular skeleton shows a highly twisted propeller-like structure with C3 symmetry. The introduction of B←N Lewis pairs not only results in a large decrease in the HOMO-LUMO gap but also lowers the LUMO to -3.00 eV. Both compounds show excellent stability with large Stokes shifts of ≤8234 cm-1 and solvatochromic emission in solvents of different polarities.

Solvent degradation and emissions from a CO2 capture pilot at a waste-to-energy plant

Degradation and emissions of amine-containing solvents from CO2 capture plants are important to address as we are getting closer to full-scale deployment. Solvent degradation and air emissions from CO2 capture with 30 wt% monoethanolamine (MEA) were monitored at a mobile capture pilot, treating flue gas from a waste-to-energy facility in Denmark. The release of nitrosamines and nitramines was shown to be below the detection limit. Preliminary results showed that the installation of an acid wash removes gaseous degradation products from the depleted flue gas by up to 83% for MEA. However, a more in-depth investigation of the acid wash performance is needed to fully make any conclusions. The release of CO, NO, NO2, SO2, NH3, and HCl was monitored over several days. Results showed that the release of these components in the depleted flue gas is affected by both the temperature in the wash tower and the process configurations. The emissions of CO, NO, NO2, SO2, NH3 and HCl in the CO2 product stream were below 5 mg/m3. Heat stable salts accumulate over time in 30 wt% MEA with formate and acetate being the main degradation products. Accumulation of iron in the solvent did not exceed 10 mg/L during the 4 month campaign. The solvent degradation and emission results obtained in this study create a solid basis for understanding potential solvent emissions to the environment from waste-to-energy plants. Currently, the accumulation of heat stable salts in amine-based solvent seems to be the main challenge. SynopsisThese results are important to control solvent based emissions and waste products in CO2 capture technology.

The Michigan–Ontario Ozone Source Experiment (MOOSE): An Overview

The Michigan–Ontario Ozone Source Experiment (MOOSE) is an international air quality field study that took place at the US–Canada Border region in the ozone seasons of 2021 and 2022. MOOSE addressed binational air quality issues stemming from lake breeze phenomena and transboundary transport, as well as local emissions in southeast Michigan and southern Ontario. State-of-the-art scientific techniques applied during MOOSE included the use of multiple advanced mobile laboratories equipped with real-time instrumentation; high-resolution meteorological and air quality models at regional, urban, and neighborhood scales; daily real-time meteorological and air quality forecasts; ground-based and airborne remote sensing; instrumented Unmanned Aerial Vehicles (UAVs); isotopic measurements of reactive nitrogen species; chemical fingerprinting; and fine-scale inverse modeling of emission sources. Major results include characterization of southeast Michigan as VOC-limited for local ozone formation; discovery of significant and unaccounted formaldehyde emissions from industrial sources; quantification of methane emissions from landfills and leaking natural gas pipelines; evaluation of solvent emission impacts on local and regional ozone; characterization of the sources of reactive nitrogen and PM2.5; and improvements to modeling practices for meteorological, receptor, and chemical transport models.

Influence of the Crusher Settings and a Thermal Pre-Treatment on the Properties of the Fine Fraction (Black Mass) from Mechanical Lithium-Ion Battery Recycling

With the increasing number of electric vehicles (EVs) rises the need to recycle their used lithium-ion batteries (LIBs). During the mechanical process of the recycling of the LIB cells, a fine fraction, the so-called black mass, is created. This black mass consists mostly of the coatings originating from the cells’ electrodes and residues from the electrolyte, together with a low amount of Al and Cu from the crushed current collector foils. The amount of black mass as well as its composition is influenced by the chosen grid size at the crusher discharge. To reduce solvent emissions during the recycling process, a thermal pre-treatment can be added before crushing, which also influences the black mass and its properties due to changes in the adhesion between electrode foils and coating. This study investigates the influence of the crusher settings as well as the pre-treatment temperatures to find an optimum between the recovery of the coating and conductive salt, while limiting the amount of Al and Cu in the black mass.

Manipulation of excited-state intramolecular proton transfer by electron-donor substitution for high performance fluoride ions sensing

Excited-state intramolecular proton transfer (ESIPT) molecules has been using as a variety of functionalityled molecular systems. To investigate the relationship between the electron-donor substitution and luminescent properties of ESIPT luminogens, four 2-(2-hydroxyphenyl) benzothiazole derivatives with donor-π-acceptor (D-π-A)-structured were synthesized. The distinct fluorescence properties of them were found to be highly dependent on the electron-donor moiety (triphenylamine and anthracenyl), its substituent position (para and meta position) and solvent polarity. The M−TPA, P-En, and M−En showed ESIPT emission in organic solvents, while the P-TPA showed intramolecular charge transfer process (ICT) emission. It is due to the synergistic effect of the aggregation-induced emission (AIE) and ESIPT, that M−TPA and M−En exhibited high solid-state quantum yields and large Stokes shifts. They were used as a probe for detecting F−, which resulted in rapid colorimetric, high sensitivity and good selectivity. The M−TPA was a turn-on fluorescent probe, which had the best detection property, and the limit of detection was as low as 11 nM. Because M−TPA displayed phenol anion emission in DMSO and F− causes the deprotonation of the M−TPA, which led to significant red shift of the absorption band and enhancement of fluorescence emission. This work provides a reliable strategy for designing high-performance fluorescent sensor via ESIPT manipulation.

Rational design of AIEE sensor: Ultrafast detection of methanol in liquid and gaseous states with highly sensitive and selective performance

The convenient and sensitive detection of methanol out of ethanol is still a great challenge due to their similar physical properties. We have designed a tetraphenylethene (TPE)-based AIEE fluorescence probe (TPEP4) with large steric hindrance composed of four large branches to overcome this challenge. Due to its four large branches, TPEP4 displayed substantially brighter fluorescence emission in aromatic solvents and a higher fluorescence quantum yield (12.67% in o-dichlorobenzene) compared to other TPE derivatives in dilute solution. Remarkably, TPEP4 exhibited a methanol-responsive fluorescence quenching in both liquid and film states. Therefore, methanol could be significantly distinguished from ethanol by the fluorescent change of TPEP4. Use of TPEP4 in biodiesel (B100) has multiple advantages, such as rapid response time (0.5 s), high selectivity to methanol, and ultralow limits of detection (LOD). In this case, the TPEP4 film remained its selectivity towards gaseous methanol with an ultralow LOD of 5.63 ppb. To the best of our knowledge, this is the first TPE-based AIEE fluorescence probe for methanol detection that shows significant potential for use in environmental monitoring. Thus, the present work provides a strategy for developing fluorescent sensing materials for volatile organic compound based on AIEE molecules.

Directionally In Situ Self-Assembled Iridium(III)-Polyimine Complex-Encapsulated Metal-Organic Framework Two-Dimensional Nanosheet Electrode To Boost Electrochemiluminescence Sensing.

Manufacturing electrochemiluminescence (ECL) electrodes to detect analytes with high performance in the aqueous phase for water-insoluble metal complexes is a great challenge. Here, a directional self-assembling avenue for in situ fabricating iridium(III)-polyimine complex-encapsulated metal-organic framework (MOF) two-dimensional electrode Hf-MOF/Ir2PD/APS/ITO is developed. The electrode displayed bright red ECL emission with high stability in the aqueous phase and specific adsorption toward ssDNA against dsDNA and mNs. That is to say, a "high-performance and multifunctional ECL electrode" is presented and explored for sensitive detection of acetamiprid (Ace) with a limit of detection of 0.0025 nM, where Ace-aptamer recognition-switched Exonuclease III-mediated digestion to make large numbers of Fc-labeled ssDNA transform into Fc-mNs. Furthermore, the proposed method was triumphantly employed to monitor the change in the residual concentration of Ace in pakchoi. This work breaks through the bottleneck of metal complex-based ECL emission in organic solvents and provides a novel strategy to develop high-performance ECL sensors.

SUSTAINABILITY IN THE PRINT AND PACKAGING INDUSTRY

In the printing and packaging industry, sustainability is defined as manufacture and practices that reflect responsibility for the environment and resources to meet the needs and expectations of future generations. In this article, raw material management, cellulose resources, industrial forests, ecological and renewable alternative fiber resources were examined in the framework of the sustainability of the printing and packaging industry. The recycling of printed materials and packaging and the effects of paper-ink types and product design in this recycling have been discussed. The effect of separation and processing at the source on the efficiency of paper recycling, economy and ecology was emphasized. The greenhouse gas emissions of solvents used in inks and cleaners, the impact on climate change, water footprint and carbon footprint issues were examined. Suggestions have been made on environmental sustainability in the printing industry, what needs to be done for a competitive production, successful optimization, minimization of waste, use of existing possibilities, recycling and evaluation of alternatives and use of clean energy.

Impact of Solvent Emissions on Reactive Aromatics and Ozone in the Great Lakes Region

While transportation emissions have declined over the past several decades, volatile organic compound (VOC) emissions from solvent use applications have increased as urban areas expand. In this work, the Canadian air quality model (GEM-MACH-TEB) is used to assess the importance of solvent emissions during the Michigan Ontario Ozone Source Experiment (MOOSE). Model predictions are compared to ozone and total mono-substituted aromatics (TOLU) observations collected in Windsor, Ontario. For summer 2018, model estimates of TOLU from solvent emissions are smaller (30% for an 8 h daytime average) in Windsor than estimates from positive matrix factorization (44% for a 24 h average). The use of updated U.S. solvent emissions from the EPA’s VCPy (Volatile Chemical Product framework) for summer 2021 simulations increases the solvent use source contribution over Detroit/Windsor (30–50% for an 8 h daytime average). This also provides a more uniform spatial distribution across the U.S./Canada border (30–50% for an 8 h daytime average). Long-chain alkanes are the dominant speciation in the model’s air pollutant emission inventory and in the observation-derived solvent use factor. Summertime 8 h daytime ozone decreased by 0.4% over Windsor for a 10% solvent use VOC emission reduction scenario. A 10% mobile NOx emission reduction scenario resulted in a 0.6% O3 decrease over Windsor and more widespread changes over the study region.