Quantum Yield In Solution Research Articles

Solution and Solid Trinitrotoluene (TNT) Photochemistry: Persistence of TNT-like Ultraviolet (UV) Resonance Raman Bands

We examined the 229 nm deep-ultraviolet resonance Raman (DUVRR) spectra of solution and solid-state trinitrotoluene (TNT) and its solution and solid-state photochemistry. Although TNT photodegrades with a solution quantum yield of ϕ ∼ 0.015, the initial photoproducts show DUVRR spectra extraordinarily similar to pure TNT, due to the similar photoproduct enhancement of the -NO2 stretching vibrations. This results in TNT-like DUVRR spectra even after complete TNT photolysis. These ultraviolet resonance Raman spectral bands enable DUVRR of trace as well as DUVRR standoff TNT detection. We determined the structure of various initial TNT photoproducts by using liquid chromatography-mass spectrometry and tandem mass spectrometry. Similar TNT DUVRR spectra and photoproducts are observed in the solution and solid states.

Synthesis and optoelectronic properties of phenylenevinylenequinoline macromolecules

A series of 3, 5 and 7 quinoline terminated arylenevinylene oligomers was selectively synthesized by applying two repetitive reactions at each cycle of oligomerization: a Wittig and Pd Heck cross-coupling. Oligomers were characterized by 1H and homo-J-resolved, DEPT-135, APT, 13C NMR and MALDI-TOF spectrometry. A detailed characterization of the oligomers was performed by UV-Vis, static-dynamic fluorescence and Z-scan spectroscopy. The HOMO and LUMO levels were determined by cyclic voltammetry and compared with the theoretical ones. Effective conjugation is attained for the pentamer, whilst the molecular structure of the heptamer shows a pronounced torsion of the phenylenevinylene segment disrupting the degree of conjugation as revealed by theoretical simulation of the oligomer geometry. Furthermore, the theoretical simulation shows that the HOMO–LUMO frontier orbitals are mainly localized in the phenylenevinylene structure, while in the quinolines the spatial distribution is only located at the CN– group without any appreciable contribution of the adjacent phenyl group. The pentamer is the most fluorescent oligomer with a quantum yield in solution of ϕ = 0.62–0.68 depending on the solvent and a fluorescence lifetime of 1.07–1.28 ns, making this oligomer suitable for optoelectronic devices.

Building Up Water-Wire Clusters: Isomer-Selective Ultraviolet and Infrared Spectra of Jet-Cooled 2-Aminopurine (H2O)n, n = 2 and 3

2-Aminopurine (2AP) is an adenine analogue with a high fluorescence quantum yield in water solution, which renders it a useful real-time probe of DNA structure. We report the ultraviolet (UV) and infrared (IR) spectra of size-selected and jet-cooled 9H-2AP·(H2O)n clusters with n = 2 and 3. Mass- and species-specific UV/UV holeburning spectroscopy allows to separate the UV spectra of four cluster isomers in the 31,200–33,000 cm(–1) spectral region with electronic band origins at 31339, 31450, 31891, and 32163 cm(–1). Using IR/UV depletion spectroscopy in combination with B3LYP calculated harmonic vibrational frequencies, the H-bonding topologies of two isomers of the n = 2 and of two isomers of the n = 3 cluster are identified. One n = 2 isomer (denoted 2A) forms a water dimer chain between the N9H and N3 atoms at the sugar-edge site, the other isomer (denoted 2D) binds one H2O at the sugar-edge site and the other at the trans-amino site between the N1 atom and the NH2 group. For 2-aminopurine·(H2O)3, one isomer (denoted 3A) forms an H-bonded water wire at the sugar-edge site, while isomer 3B accommodates two H2O molecules at the sugar-edge and one at the trans-amino site. The approximate second-order coupled cluster (CC2) method predicts the adiabatic S1 ← S0 transitions of 9H-2-aminopurine and six water cluster isomers with n = 1–3 in very good agreement with the experimental 0(0)(0) frequencies, with differences of <0.6%. The stabilization of the S1(ππ*) state of 2-aminopurine by water clusters is highly regiospecific: Isomers with one or two H2O molecules H-bonded in the trans-amino position induce large spectra red shifts, corresponding to 1ππ* state stabilization of 10–12 kJ/mol, while water-wire cluster solvation at the sugar-edge leads to much smaller stabilization. The evolution of the IR spectra of the water-wire clusters with n = 1–3 that are H-bonded to the sugar-edge site is discussed. Qualitatively different regions (denoted I to IV) can be attributed to the different free and H-bonded OH, NH, NH2 and OH···OH water-wire stretch vibrations.

Development of Selective Detection Method for 5-Formyl-2′-Deoxyuridine in DNA Using a Fluorogenic Reagent

It is important that various lesions in DNA were detected selectively and conveniently to know mechanisms of carcinogenicity and/or aging of cells. However, most detection methods of DNA lesion are complicated and take a long time for enzymatic hydrolysis and analysis by HPLC and/or mass spectrometry. This review shows the new concept for detection of DNA lesion by "fluorogenic reagent". Inspired by the unique bis-heteroaryl structure of luciferin and 5-heteroaryl-2'-deoxyuridine having good fluorescence properties, we designed and synthesized fluorogenic reagent 4,5-dimethoxy-2-aminothiophenol for a selective and convenient detection for 5-formyl-2'-deoxyuridine, which is generated in yields comparable to that of 2'-deoxy-8-oxoguanosine, in DNA. Generated 5-(5,6-dimethoxybenzothiazol-2-yl)-2'-deoxyuridine has a high quantum yield and larger Stokes shift in aqueous solution. This derivatization of 5-formyl-2'-deoxyuridine in oligodeoxynucleotide occurred quickly and quantitatively. The fluorogenic reagent was also revealed to detect 5-formyl-2'-deoxyuridine in γ-irradiated calf thymus DNA with irradiation dose dependent manner. Thus, our fluorogenic strategy enables to selective and convenient detection of lesion in DNA exposed to various forms of oxidative stress.

Synthesis, fine structure of 19F NMR and fluorescence of novel amorphous TPA derivatives having perfluorinated cyclopentenyl and benzo[b]thiophene unit

Three novel triphenylamine (TPA) derivatives having perfluorinated cyclopentenyl and benzo[b]thiophene unit are obtained from 4-bromo-N,N-diphenyl-2-methylbenzo[b]thiophen-5-amine. The new compounds are expected to find their use in thin film devices as charge transport materials and host organic light-emitting materials. It is found that the new compounds show relatively strong fluorescence either in solution or in solid state, and are amorphous due to a special conformation which is elucidated by the fine structure of 19F NMR. Molecular structure and properties of these compounds is characterized by 1H NMR, 13C NMR (broadband decoupled), ESI–HRMS, elemental analysis and thermal analysis (DSC). Fluorescent quantum yield in solution is measured using 9,10-diphenylanthrancene (DPA) as standard fluorescent substance.

Polymorph, assembly, luminescence and semiconductor properties of a quinacridone derivative with extended π-conjugated framework

The structures and properties of an indole-ring-fused quinacridone derivative 5,8,15,18-tetraoctyl-5,8,15,18-tetrahydroindolo[3,2-a]indole[3′,2′ : 5,6]quinacridone (IDQA), which was synthesized by an improved procedure, have been carefully investigated and compared with its parent compound N,N′-di(n-octyl)quinacridone (C8-QA). Concentration-dependent 1H NMR spectra revealed that the strong aggregations of IDQA existed in solution because of the flat and extended π-conjugation. Two polymorphs of IDQA with and without π⋯π interactions exhibited red and non emissions, respectively. One-dimensional micromaterials with different morphologies constructed by IDQA molecules were fabricated by a reprecipitation approach and they displayed different emission properties due to the different molecular packing. The nine-ring fused flat skeleton endowed this material with several elegant properties, including a high photoluminescent quantum yield in solution, and a high thermal and electrochemical stability. Therefore, the efficient doped organic light emitting device (OLED) with IDQA as the emitter was fabricated. Moreover, the large π-conjugation system endowed the IDQA thin film with ordered molecular packing and good hole transport properties (hole mobility μh = 0.047 cm2 V−1 s−1).

New organic–inorganic hybrid materials based on perylene diimide–polyhedral oligomeric silsesquioxane dyes with reduced quenching of the emission in the solid state

Abstract Solid state luminescent materials are the subject of ever growing interest both from a scientific and a technological point of view because high-tech applications of light emitting materials very often require their use in the condensed phase. Aggregation caused quenching processes however represent an obstacle to the development of most luminogens in the condensed phase. This is why particularly fascinating are those materials showing high emission intensity in the solid state. Aggregation caused quenching is particularly detrimental for π-extended polycyclic aromatic hydrocarbons, for example perylene tetracarboxylic acid diimides which are characterized by a near-unity fluorescence quantum yield in solution but are far less emissive in the solid state. Here we report on the easy preparation and on the optical investigation of perylene tetracarboxylic acid diimide derivatives linked to the inorganic cage of polyhedral oligomeric silsesquioxanes. These new hybrid perylene diimide–polyhedral oligomeric silsesquioxane dyes show in solution the typical absorption and emission features of the perylene diimide fragment, with a quantum efficiency close to unity. Moreover, in the solid state (both as spin-coated films and powders) the electronic absorption spectra indicate a reduced fluorophore aggregation and significant quantum yield efficiencies induced by the positive effect of the polyhedral oligomeric silsesquioxane cage.

Efficient Greenish Blue Electrochemiluminescence from Fluorene and Spirobifluorene Derivatives

The spectroscopic and electrochemical behavior as well as electrogenerated chemiluminescence (ECL) of a series of donor-π-donor derivatives bearing triphenylamine groups as donor connected to a fluorene, 2,7-bis-(4-(N,N-diphenylamino)phen-1-yl)-9,9'-dimethylfluorene (1), or spirobifluorene core, 2,7-bis-(4-(N,N-diphenylamino)phen-1-yl)-9,9'-spirobifluorene (2) and 2,2',7,7'-tetrakis(4-(N,N-diphenylamino)phen-1-yl)-9,9'-spirobifluorene (3), were investigated. Besides a high photoluminescence (PL) quantum yield in solution (between 81 and 87%), an efficient radical ions annihilation process induces intense greenish blue ECL emission that could be seen with the naked eye. Only the tetrasubstituted spirobifluorene derivative (compound 3) shows weak ECL obtained by a direct annihilation mechanism. Because the energy of the annihilation reaction is higher than the energy required to form the singlet excited state, the S-route could be considered the pathway followed by the ECL process in these molecules. The ECL emissions recorded by direct ion-ion annihilation show two bands compared to the single structureless PL band. The ECL spectra obtained by a coreactant approach using benzoylperoxide as a coreagent show no differences relative to that produced by annihilation, except for an increasing of ECL intensity for all compounds.

Lighting‐Up of the Dye Malachite Green with Mercury(II)–DNA and Its Application for Fluorescence Turn‐Off Detection of Cysteine and Glutathione

This work describes a novel strategy for the highly sensitive and selective detection of cysteine (Cys) and glutathione (GSH) based on the Hg(2+)-AGRO100-malachite green (MG) complex system. The dye MG, which has a very low quantum yield in aqueous solution by itself, can bind with the thymine-rich DNA AGRO100 in the presence of Hg(2+) ions to generate a striking fluorescence intensity enhancement of 1000-fold. As sulfur-containing amino acids, Cys and GSH effectively sequester Hg(2+) ions from the Hg(2+)-AGRO100-MG complex structure to switch the 'lit-up' chemosensor to the 'off' state (about a 50-fold fluorescence intensity decrease), thus providing a facile, but effective, method to probe for Cys/GSH. The fluorescence titration, UV absorption, CD, and Raman spectra provide some insight into the structural and chemical basis for the enhancement effect. The formation of the Hg(2+)-AGRO100-MG complex significantly affects the electronic structure and conformation of the MG molecule by leading to an extended π system, which is the likely origin of the observed striking fluorescence intensity enhancement. Notably, the proposed sensing platform exhibits exquisite selectivity and sensitivity toward Cys/GSH with limits of detection of 5 nM for Cys and 10 nM for GSH, respectively. Furthermore, the straightforward assay design avoids labeling of the probe, uses only commercially available materials, and still displays comparable sensitivity and excellent selectivity.

Ensemble Brightening and Enhanced Quantum Yield in Size-Purified Silicon Nanocrystals

We report on the quantum yield, photoluminescence (PL) lifetime, and ensemble photoluminescent stability of highly monodisperse plasma-synthesized silicon nanocrystals (SiNCs) prepared though density-gradient ultracentrifugation in mixed organic solvents. Improved size uniformity leads to a reduction in PL line width and the emergence of entropic order in dry nanocrystal films. We find excellent agreement with the anticipated trends of quantum confinement in nanocrystalline silicon, with a solution quantum yield that is independent of nanocrystal size for the larger fractions but decreases dramatically with size for the smaller fractions. We also find a significant PL enhancement in films assembled from the fractions, and we use a combination of measurement, simulation, and modeling to link this "brightening" to a temporally enhanced quantum yield arising from SiNC interactions in ordered ensembles of monodisperse nanocrystals. Using an appropriate excitation scheme, we exploit this enhancement to achieve photostable emission.

Sensitive Sensor for Mercury Ion in Aqueous Solution by "Naked-eye" and Fluorescence Recognition

A sensitive and selective Nile blue-based optical sensor 1-benzoyl-3-{2-[9-(ethylamino)-10-methyl-9H-benzo[α]phenoxazin-5-ylamino]ethyl}thiourea hydrochloride(NBET) in aqueous solution for Hg2+ was synthesized.The maximum absorption peak of the probe molecule appeared at 640 nm,and decreased upon the addition of Hg2+ in 0.05 mol/L Tris-HCl buffer solution at pH=7.4,a new peak of absorption at 556 nm was observed.The color of the solution changed from light blue to light purple.There was neglectable change upon the addition of other metal ions.Fluorescence monitoring revealed a fluorescence quenching of the probe's characteristic emission at 660 nm upon the addition of Hg2+.The probe possessed the advantages of near-infrared excitation and emission and high fluorescence quantum yield in aqueous solution and offer an opportunity to detect Hg2+ by a naked-eye manner.Limit of detection of fluorescence spectral for Hg2+ was found to be 0.005 μmol/L in aqueous solution.

Propylamino-connected fluorescent terpyridine dimer and trimer: syntheses, photophysical properties and formation of duplex-type complexes with Cd(ii)

By using propylamine as a connector, a dimer (L2) and trimer (L3) of 2,2':6',2''-terpyridine (tpy) are synthesized. They showed the lowest energy π–π* absorption at 354 nm and blue fluorescence at 420 nm with a moderate quantum yield in solution. Spectral titrations, electrospray ionization mass spectrometry (ESI-MS), (1)H–(1)H rotating-frame nuclear Overhauser effect correlation spectroscopy (ROESY), and structure simulation (MOPAC/PM5) indicated that both L2 and L3 form duplex-type multi-component complexes with Cd(II), [Cd(2)(L2)(2)](4+) and [Cd(3)(L3)(2)](6+), respectively. While the luminescence of these complexes was quite weak in solution (quantum yield Φ < 0.005), the complexes showed enhanced emission in the solid state with remarkable increase of the quantum yield (Φ = 0.13).

The ‘double dendron’ approach to host free phosphorescent poly(dendrimer) OLEDs

The addition of dendrons to iridium(III) complexes attached to a poly(styrene) backbone is shown to improve the physical and optoelectronic properties of the phosphorescent materials. The iridium(III) complexes have two 2-phenylpyridyl ligands and one phenyltriazolyl ligand, with the latter providing the attachment point to the polymer backbone. It was found that by increasing the number of dendrons (from zero to two) per 2-phenylpyridyl ligand, the intra- and interchain interactions could be more effectively controlled. The poly(dendrimer) with two dendrons per ligand had solution and solid-state photoluminescence quantum yields of 67% and 47%, respectively. Organic light-emitting diodes containing the doubly dendronised (two dendrons per ligand) poly(dendrimer) had a low turn on voltage of 3.6 V (>1.0 cd m−2), a maximum luminance of 6 700 cd m−2 (at 12.2 V), and 100 cd m−2 was achieved at 6.0 V with an external quantum efficiency (EQE) of 9.2% (28.1 cd A−1) and power efficiency of 14.7 lm/W. A solution of the doubly dendronised poly(dendrimer) in N-methyl-2-pyrolidinone was found to have a viscosity of 4.6 mPa s, which falls in the range of solutions that can be inkjet printed.

Short and scalable synthesis of an anhydride precursor of the environment-sensitive fluorophore 6-dimethylaminonaphthalimide

Environment-sensitive fluorophores have different quantum yields in different solvents. 6-Dimethylaminonaphthalimide (6-DMN), for example, has a low quantum yield in aqueous solutions, but is highly fluorescent in nonpolar solvents or when bound to hydrophobic sites in proteins or membranes. 6-DMN has been used to investigate protein-protein interactions, as well as the in-tissue distribution and internalization of δ-receptors. This protocol describes a highly efficient three-stage synthesis of 6-dimethylamino-2,3-naphthalenedicarboxylic anhydride (compound 1), which is a stable precursor that can be converted to 6-DMN. The three stages are (i) photo-bromination of 4-nitro-o-xylene (yield 82%), (ii) Diels-Alder reaction followed by base hydrolysis, resulting in 6-nitro-2,3-naphthalenedicarboxylic acid (yield 87%) and (iii) reductive amination followed by dehydration (yield 76.5%) to form compound 1. The synthesis can be performed on a gram scale (in 55 h over 3 d) with an overall yield of about 55%. It can easily be modified to prepare related compounds by, for example, performing different reactions using 6-nitro-2,3-naphthalenedicarboxylic acid.

Fluorescence Properties of 5‐(5,6‐Dimethoxybenzothiazol‐2‐yl)‐2′‐deoxyuridine (dbtU) and Oligodeoxyribonucleotides Containing dbtU

AbstractWe describe the synthesis and photophysical properties of 11 substituted 5‐(benzothiazol‐2‐yl)‐2′‐deoxyuridine derivatives and oligodeoxyribonucleotides (ODNs) containing 5‐(5,6‐dimethoxybenzothiazol‐2‐yl)‐2′‐deoxyuridine (dbtU), which was the strongest fluorescent derivative among those prepared. The fluorescence properties of dbtU itself and ODNs containing dbtU show the same tendency of being weaker in both neutral and acidic solution and stronger in basic solution. The ODNs (15mer) containing 16 combinations of 5′‐XbtU‐3′ and 5′‐btUY‐3′, where X, Y = A, T, G, or C, were synthesized, and their fluorescence intensity and quantum yield in basic solution were compared. On average, only the ODN with the 5′‐GbtU‐3′ sequence shows a 7.9‐fold lower fluorescence intensity than the other sequences. Ab initio calculations of 5′‐GbtU‐3′ and 5′‐btUG‐3′ as models under basic conditions suggest that the lower fluorescence of the ODN containing the 5′‐GbtU‐3′ sequence is caused by a wider overlap between stacked guanine (Gua) and btUra than that of the 5′‐btUG‐3′ sequence and that the HOMO is delocalized not only on btUra but also on Gua.

Synthesis and Characterization of Luminescent Polystyrene Derivatives with Sterically Protected Fluorenyl- and Carbazolylborane Moieties

Polystyrene was functionalized with luminescent fluorenyl- and carbazolylborane pendant moieties. Because of an interaction of the empty p orbital on boron with the extended π-systems of fluorene or carbazole, the resulting polymeric materials exhibit intense blue emission with maxima in the range 390–420 nm. The solution quantum yields were 65% for the fluorene derivative and 68 and 11% for two different carbazole derivatives, respectively. The stability of the borylated polymers was enhanced by attachment of a bulky triisopropylphenyl group to each of the boron centers. Thus, the polymers were found to be stable for a period of over 1 month. Thermal stability up to ca. 250 °C was confirmed by thermogravimetric analysis.

Chiral Donor Photoinduced‐Electron‐Transfer (d‐PET) Boronic Acid Chemosensors for the Selective Recognition of Tartaric Acids, Disaccharides, and Ginsenosides

A modular approach was proposed for the preparation of chiral fluorescent molecular sensors, in which the fluorophore, scaffold, and chirogenic center can be connected by ethynyl groups, and these modules can easily be changed to other structures to optimize the molecular sensing performance of the sensors. This modular strategy to assembly chiral sensors alleviated the previous restrictions of chiral boronic acid sensors, for which the chirogenic center, fluorophore, and scaffold were integrated, thus it was difficult to optimize the molecular structures by chemical modifications. We demonstrated the potential of our new strategy by the preparation of a sensor with a larger scaffold. The photoinduced electron-transfer (PET) effect is efficient even with a large distance between the N atom and the fluorophore core. Furthermore, the rarely reported donor-PET (d-PET) effect, which was previously limited to carbazole, was extended to phenothiazine fluorophore. The contrast ratio, that is, PET efficiency of the new d-PET sensor, is increased to 8.0, compared to 2.0 with the previous carbazole d-PET sensors. Furthermore, the ethynylated phenothiazine shows longer excitation wavelength (centered at 380 nm) and emission wavelength (492 nm), a large Stokes shift (142 nm), and high fluorescence quantum yield in aqueous solution (Φ=0.48 in MeOH/water, 3:1 v/v). Enantioselective recognition of tartaric acid was achieved with the new d-PET boronic acid sensors. The enantioselectivity is up to 10 (ratio of the binding constants toward D- and L-tartaric acid, k(D)/k(L)). A consecutive fluorescence enhancement/decrease was observed, thus we propose a transition of the binding stoichiometry from 1:1 to 1:2 as the analyte concentration increases, which is supported by mass spectra analysis. The boronic acid sensors were used for selective and sensitive recognition of disaccharides and glycosylated steroids (ginsenosides).

Ionic-liquid-induced microfluidic reaction for water-solubleCe1 − xTbxF3 nanocrystal synthesis

Luminescent lanthanide nanocrystals (NCs) are proposed to be a promising newclass of fluorescent labeling agents due to their attractive optical and chemicalfeatures including low toxicity, wide photoluminescence (PL) emission and highresistance to photobleaching. In this paper, an ionic-liquid-induced synthesis ofCe1 − xTbxF3 nanoparticle was investigated via utilizing a capillary microreactor. Ionic liquid-[bmim]BF4 acts as both a fluoride source and stabilizing solvent during the reaction, which was shownto be a key factor that governs luminescence intensity of the obtained nanoparticles. Theluminescent properties can be greatly improved by optimizing the volume percentage of[bmim]BF4. Furthermore, the reaction temperature exerts an influence on the properties ofthe prepared samples. Experimental results show that the colloidal solutions ofTb3 + -dopedCeF3 NCs exhibit thecharacteristic emission of Ce3 + 5d–4f and Tb3 + 5 D4–7FJ (J = 6–3) transitionswith 5D4–7F5 green emission at 542 nm as the strongest peak. The as-prepared samples are founddispersible in water with the quantum yield (in aqueous solution) as 12%, which indicates apotential application on biolabels, light-emitting diodes (LEDs) and redox luminescentswitches.

Synthesis, characterization and luminescence properties of copper(I) complexes containing 2-phenyl-3-(benzylamino)-1,2-dihydroquinazolin-4(3H)-one and triphenylphosphine as ligands

Some copper(I) complexes of the formula [Cu( L)(PPh 3) 2]X ( 1– 4) [where L = 2-phenyl-3-(benzylamino)-1,2-dihydroquinazolin-4(3H)-one; PPh 3 = triphenylphosphine; X = Cl −, NO 3 −, ClO 4 − and BF 4 −] have been prepared and characterized on the basis of elemental analysis, IR, UV–Vis and 1H NMR spectral studies. The representative complex of the series 4 has been characterized by single crystal X-ray diffraction which reveal that in the complex the central copper(I) ion assumes the irregular distorted-tetrahedral geometry. Cyclic voltammetry of the complexes indicate a quasireversible redox behavior corresponding to Cu(II)/Cu(I) couple. All the complexes exhibit intraligand (π → π ∗) fluorescence with high quantum yield in dichloromethane solution.

Production of Reactive Oxygen Species by Photoactive Anthraquinone Compounds and Their Applications in Wastewater Treatment

2-Anthraquinone sulfonate (2-AQS) was found to exhibit an abnormally high singlet-oxygen quantum yield in aqueous solution after UVA irradiation based on a widely used testing method for singlet oxygen. To discover the cause of the abnormal results, several possible reactive oxygen species were also measured in the system. Results revealed that 2-AQS and two other similar compounds produced singlet oxygen, hydroxyl radicals, and superoxide, so-called reactive oxygen species (ROS), under UVA exposure. The production of hydroxyl radical contributed to the abnormally high quantum yield. Quantifications of the ROS produced by these compounds were conducted by oxidation of p-nitrosodimethylaninline in the presence and absence of either l-histidine or superoxide dismutase. EPR results also confirmed the formation of singlet oxygen by these compounds under UVA irradiation. The influence of different exposure times on the formation of ROS was measured for all three photosensitive compounds. The effects of different additives on the production of ROS were also investigated. The results showed that some compounds traditionally known as “hydroxyl radical scavengers” instead served as hydroxyl radical “generation promoters” under UVA exposure in the system. Moreover, for the first time, these photosensitive compounds were used to degrade a textile colorant, namely, Reactive Black 5, achieving the total decoloration of this compound within 10 min.