Electron-accepting Ability Research Articles

A Perspective on 2D Fused-Ring Quad-Rotor-Shaped Nonfullerene Acceptors with an Anthracene Core.

Previous studies have demonstrated the remarkable properties of quad-rotor-shaped two-dimensional nonfullerene acceptors (2D NFAs), which encompass exceptional electron affinity, robust sunlight absorption, effective exciton separation, and accelerated electron transfer capabilities. Naphthalene has been demonstrated to be a significant 2D fused core to construct high-performance 2D NFAs. However, synthesizing such materials through existing synthetic pathways poses a significant challenge. In this work, we designed four 2D NFAs (TEA-SIC, TEA-SIC-8F, TEA-SIC-OH, and TEA-SIC-OH-8F) with an anthracene core. These NFAs can theoretically be synthesized into a quad-rotor configuration through a seven-step synthetic process. Theoretical calculations have demonstrated that these 2D NFAs exhibit superior electron-accepting abilities, enhanced sunlight absorption, and more efficient exciton dissociation compared to Y6. Furthermore, TEA-SIC and TEA-SIC-8F exhibited impressive electron mobilities of 1.76 × 10-3 cm2 V-1 s-1 and 1.18 × 10-3 cm2 V-1 s-1, respectively, indicating their suitability for the development of high-performance organic solar cells (OSCs). Although TEA-SIC-OH and TEA-SIC-OH-8F have lower electron mobility, their high sunlight absorption and efficient exciton separation suggest potential as third components in ternary OSCs. These 2D NFAs also exhibit a commendable solubility in most alcohol-based solvents, indicating their potential for specialized applications in the fabrication of stacked OSCs. These findings provide valuable insights for the future design of synthesizable high-performance 2D NFAs.

The flotation separation of galena from pyrite with 2-dialkylamino-s-triazine-4-thiol-6(1H)-thione sodium at pH ∼8.0: Emphasize on adsorption mechanism

To achieve an eco-friendly flotation separation of galena from pyrite under the low alkaline and depressant-free conditions, the triazine-dithione surfactants, such as 2-dimethylamino-s-triazine-4-thiol-6(1H)-thione sodium (DMN), 2-diethylamino-s-triazine-4-thiol-6(1H)-thione sodium (DEN) and 2-dibutylamino-s-triazine-4-thiol-6(1H)-thione sodium (DBN) were designed as the special collectors for galena. The micro-flotation results showed that the collecting capacity of these three collectors towards galena was in the order of DBN > DEN ≫ DMN, being consistent with their hydrophobization ability. In-situ AFM observed the aggregation of DBN on the whole surface of galena, which significantly enhanced the contact angle of galena. UV spectra and zeta potential recommended that the affinity of DBN towards lead ions and galena was much stronger than ferrous/ferric ions and pyrite. DFT (density functional theory) calculation revealed DBN’s two exo-S atoms were of its electron-donating center. And XPS confirmed the bonding interaction of the two exo-S atoms with Pb(Ⅱ) atoms on/in galena surface. DBN owned the mild electron-donating capacity and strong electron-accepting ability, and realized the eco-friendly flotation separation of galena from pyrite at pH ∼8.0.

Self-coupling of electron acceptor units in conjugated microporous polymers strengthening local donor-acceptor interaction for improving photocatalytic activity

The partial self-coupling of donor or acceptor unit during donor-acceptor (D-A) type CMPs synthesis is often overlooked for the effect on photocatalytic activity. Herein, we developed three D-A type CMPs, named SATE-CMP-n (n=1–3), which were constructed from triazine (TEPT) unit (A) and three salen units (D). With the rigidity of salen units increasing (the rigidity: salen-1 <salen-2 <salen-3), the self-coupling proportion of TEPT decreases. The experiments and DFT calculations reveal that salen-1 has the stronger electron-donating ability compared to salen-2 and salen-3, and that the self-coupling of TEPT units also enhances the electron-accepting ability. Therefore, SATE-CMP-1 exhibits the strongest D-A interaction and the highest separation and transfer efficiency of charge carriers, and has been used a photocatalyst for S−S and S−N coupling reactions. This work proves that the self-coupling of monomers in the construction of CMPs is not overlooked for adjusting the photocatalytic activity of catalyst.

In situ nitrogen-doped graphene-TiO2 nano-hybrid as an efficient photocatalyst for pollutant degradation.

To solve environmental-related issues (wastewater remediation, energy conservation and air purification) caused by rapid urbanization and industrialization, synthesis of novel and modified nanostructured photocatalyst has received increasing attention in recent years. We herein report the facile synthesis of in situ nitrogen-doped chemically anchored TiO2 with graphene through sol-gel method. The structural analysis using X-ray diffraction showed that the crystalline nitrogen-doped graphene-titanium dioxide (N-GT) nanocomposite is mainly composed of anatase with minor brookite phase. Raman spectroscopy revealed the graphene characteristic band presence at low intensity level in addition to the main bands of anatase TiO2. X-ray photoelectron spectroscopy analysis disclosed the chemical bonding of TiO2 with graphene via Ti-O-C linkage, also the substitution of nitrogen dopant in both TiO2 lattice and into the skeleton of graphene nanoflakes. UV-Vis absorption spectroscopy analysis established that the modified material can efficiently absorb the longer wavelength range photons due to its narrowed band gap. The N0.06-GT material showed the highest degradation efficiency over methylene blue (MB, ∼98%) under UV and sulfamethoxazole (SMX, ∼ 90.0%) under visible light irradiation. The increased activity of the composite is credited to the synergistic effect of high surface area via greater adsorption capacity, narrowed band gap via increased photon absorption, and reduced e-/h+ recombination via good electron acceptability of graphene nanoflakes and defect sites (Ti3+ and oxygen vacancy(Vo)). The ROS experiments further depict that primarily hydroxyl radicals (OH•) and superoxide anions (O2•-) are responsible for the pollutant degradation in the process redox reactions. In summary, our findings specify new insight into the fabrication of this new material whose efficiency can be further tested in applications like H2 production, CO2 conversion to value-added products, and in energy conservation and storage.

Enhanced Thermally Activated Delayed Fluorescence by Sole Coordination: From an Organic Molecule to Its Zinc Complex.

A BPAPTPyC organic molecule containing a sandwich structural chromophore is designed and synthesized to produce blue thermally activated delayed fluorescence (TADF). The chromophore is composed of two di(4-tert-butylphenyl)amino donors and one inserted terpyridyl acceptor hitched at positions 1, 8, and 9 of a single carbazole via the p-phenylene group, in which the multiple space π-π interactions between the donor and acceptor enable the molecule to possess the TADF feature with a high energy emission at 470 nm but a low photoluminescence quantum yield (PLQY) and a small proportion of the delayed component. In contrast, the corresponding Zn(BPAPTPyC)Cl2 complex has a high PLQY and a short lifetime with a red-shifted emission due to the enhanced rigidity and electron accepting ability of the terpyridyl group from coordination. A solution-processed organic light-emitting diode (OLED) based on the complex achieves a maximum external quantum efficiency (EQE) of 17.9% with an emission peak at 585 nm, while an OLED of the organic molecule produces blue emission with a maximum EQE of 2.7%.

Tweezer Dyads for H-Bond Assisted Cooperativity in Tandem Uncaging Systems.

"Tandem" uncaging systems, in which a photolabile protecting group (PPG) is sensitized by an energy-harvesting antenna, may increase the photosensitivity of PPGs by several orders of magnitude for two-photon (2P) photorelease. Yet, they remain poorly accessible because of arduous multi-step synthesis. In this work, we design efficient tandem uncaging systems by (i) using a convenient assembly of the building blocks relying on click chemistry, (ii) introducing H-bonding induced proximity thus facilitating (iii) photoinduced electron transfer (PeT) as a cooperative mechanism. A strong two-photon absorber electron-donating quadrupolar antenna and various electron-accepting PPGs (mDEAC, MNI or MDNI) were clicked stepwise onto a "tweezer-shaped" pyrido-2,6-dicarboxylate platform whose H-bonding and π-stacking abilities were exploited to keep the antenna and the PPGs in close proximity. The different electron-accepting ability of the PPGs led to dyads with wildly different behaviors. Whilst the MDNI and MNI dyads showed poor dark stability or no photo-uncaging ability due to their too high electron-accepting character, the mDEAC dyad benefited from optimum redox potentials to promote PeT and slow down charge recombination, resulting in enhanced uncaging quantum yield (Φu=0.38) compared to mDEAC (Φu=0.014). This unique combination resulted in large 2P photo-sensitivity in the near-infrared window (240 GM at 710 nm).

Theoretical insights into the linker effects on the turn-on fluorescence behaviors in pyridazinone-containing NO probes

Fluorescent probes with preferred photophysical properties have attracted considerable attention for their advantages in real-time and accurate detection of signalling molecules in living organisms. Nitric oxide (NO) is a ubiquitous cellular messenger closely associated with many physiological and pathological processes. A NO fluorescent probe, PYSNO, based on the pyridazinone (PY) scaffold with o-phenylenediamine as the receptor and thiophene (S) as the linker has been synthesized. Inspired by the experimental guidance, three other dyes (PYSSNO, PYSONO and PYONO) were theoretically designed by replacing the S linker with thieno[3,2-b]thiophene (SS), thieno[3,2-b]thiophene 1,1-dioxide (SO) and thiophene 1,1-dioxide (O) groups. The photophysical properties were theoretically investigated in aqueous solution, by the combined time-dependent density functional theory, polarizable continuum model and thermal vibration correlation function approaches. Our results indicate that the emission wavelengths of all the designed dyes show red shifts due to either an increase in the conjugation length or electron-accepting ability of the linkers compared to PYSNO. The photoinduced electron transfer (PET) processes are all absent in these systems. PYSSNO and PYSONO are theoretically expected to be promising candidates for novel NO fluorescent probes, but the suitability of PYONO as a NO probe is compromised by the predicted non-luminescent emission before and after reaction with NO. Our study not only offers valuable insights into the detailed structure–property relationships, but also opens a new avenue for the rational design of efficient fluorescent sensors for NO detection.

Highly efficient flotation of ilmenite with a novel dithiocarbamate-hydroxamate collector

The pre-activation of lead nitrate has been extensively proved to be an effective technique in ilmenite flotation, and sodium oleate is the preferred collector. Realization the clean flotation of ilmenite is an important aspect to respond the green and low-carbon policy. In this work, a dithiocarbamate-hydroxamate collector OAHD was pioneeringly added into the direct flotation of ilmenite as an efficient collector. The micro-flotation performance found that OAHD realized an efficient flotation of ilmenite under low concentration of 1.0 × 10−5 mol/L under around pH 8.0, and the flotation recovery rate of ilmenite reached about 94.2%, which was about 35.8% higher than that of NaOL. The morphology of ilmenite observed by AFM probed the self-assemble adsorption behavior of OAHD on ilmenite surface. DFT (density functional theory) calculations suggested that both dithiocarbamate and hydroxamate groups are the chemical active centers and have strong electron acceptability of d-orbital electrons of Fe atoms at/on the interface of ilmenite. UV–Vis spectra demonstrated that dithiocarbamte and hydroxamate groups simultaneously has strong chemical reaction with Fe2+ ions. XPS analysis recommended that OAHD chemisorbed on ilmenite surface to produce the surface Fe(II)-OAHD complexes where the O,O-five membered ring of Fe(II)-hydroxamate compounds were formed.

Efficient water-soluble copper(II) complexes with SOD/CO-like activities and the relationship between their structure and activity

Superoxide dismutase is a significant member of the body’s natural antioxidant defense system. It can effectively eliminate superoxide anion free radicals from the body. Based on the functionalized ligand-isonicotinic acid, three copper complexes were successfully developed. The metal centers of complexes 1–3 were highly similar to the active sites of natural superoxide dismutase. It was found that complexes 1–3 exhibited both excellent superoxide dismutase (SOD)-like and catecholase (CO)-like activities at the same time. A model of oxidative stress, induced by hydrogen peroxide, was constructed based on the cytotoxicity test. In this model, the mimetic complex proved to have effective intracellular antioxidant capacity. Combined with the experimental data and DFT, the results showed that the electron acceptance ability and the coordination configuration of the active center of copper ions had important effects on the activity of SOD.

Mechanistical Insights into the Ultrasensitive Detection of Radioactive and Chemotoxic UO22+ Ions by a Porous Anionic Co-Metal-Organic Framework.

Development of a simple, cost-efficient, and portable UO22+ sensory probe with high selectivity and sensitivity is highly desirable in the context of monitoring radioactive contaminants. Herein, we report a luminescent Co-based metal-organic framework (MOF), {[Me2NH2]0.5[Co(DATRz)0.5(NH2BDC)]·xG}n (1), equipped with abundant amino functionalities for the selective detection of uranyl cations. The ionic structure consists of two types of channels decorated with plentiful Lewis basic amino moieties, which trigger a stronger acid-base interaction with the diffused cationic units and thus can selectively quench the fluorescence intensity in the presence of other interfering ions. Furthermore, the limit of detection for selective UO22+ sensing was achieved to be as low as 0.13 μM (30.94 ppb) with rapid responsiveness and multiple recyclabilities, demonstrating its excellent efficacy. Density functional theory (DFT) calculations further unraveled the preferred binding sites of the UO22+ ions in the tubular channel of the MOF structure. Orbital hybridization between NH2BDC/DATRz and UO22+ together with its significantly large electron-accepting ability is identified as responsible for the luminescence quenching. More importantly, the prepared 1@PVDF {poly(vinylidene difluoride)} mixed-matrix membrane (MMM) displayed good fluorescence activity comparable to 1, which is of great significance for their practical employment as MOF-based luminosensors in real-world sensing application.

Tetraanionic Oligo-Dioxaborines: Strongly Absorbing Near-Infrared Dyes.

Polymethine dyes of tetraanionic nature comprising 1,3,2-dioxaborine rings in the polymethine chain and end-groups of different electron-accepting abilities have been synthesized. They can be considered as oligomeric polymethines, where a linear conjugated π-system passes through three 1,3,2-dioxaborine units and a number of tri- and dimethine π-bridges between two end-groups. The obtained dyes exhibit near-infrared absorption and fluorescence, with molar absorption coefficients reaching as high as 564000 M-1 cm-1 in DMF, rendering them among the strongest absorbers known. The novel compounds are bright NIR fluorophores, with fluorescence quantum yields up to 0.13 in DMF. A comparative analysis of the electronic structure of the obtained dyes with respective dianionic and trianionic oligomers was conducted through quantum chemical calculations.

Understanding Bonding Nature of α‐Keggin Polyoxometalates [XW12O40]n− (X = Al, Si, P, S): A Generalized Superatomic Perspective

α‐Keggin polyoxometalates (POMs) [XW12O40]n− (X = Al, Si, P, S) are widely used in batteries owing to their remarkable redox activity. However, the mechanism underlying the applications appears inconsistent with the widely accepted covalent bonding nature. Here, first‐principles calculations show that XW12 are core–shell structures composed of a shell and an XO4n− core, both are stabilized by covalent interactions. Interestingly, owing to the presence of a substantial number of electrons in W12O36 shell, the frontier molecular orbitals of XW12 are not only strongly delocalized but also exhibit superatomic properties with high‐angular momentum electrons that do not conform to the Jellium model. Detailed analysis indicates that energetically high lying filled molecular orbitals (MOs) have reached unusually high‐angular momentum characterized by quantum number K or higher, allowing for the accommodation of numerous electrons. This attribute confers strong electron acceptor ability and redox activity to XW12. Moreover, electrons added to XW12 still occupy the K orbitals and will not cause rearrangement of the MOs, thereby maintaining the stability of these structures. Our findings highlight the structure–activity relationship and provide a direction for tailor‐made POMs with specific properties at atomic level.

Multifacets of Fullerene-Metal Clusters: From Fundamental to Application.

ConspectusBuckminsterfullerene, C60, was discovered through a prominent mass peak containing 60 atoms produced from laser vaporization of graphite, driven by Kroto's interest in understanding the formation mechanisms of carbon-containing molecules in space. Inspired by the geodesic dome-shaped architecture designed by Richard Buckminster Fuller, after whom the particle was named, C60 was found to have a football-shaped structure comprising 20 hexagons and 12 pentagons. It sparked worldwide interest in understanding this new carbon allotrope, resulting in the awarding of the Noble Prize in Chemistry to Smalley, Kroto, and Curl in 1996.Intrinsically, C60 is an exceptional species because of its high stability and electron-accepting ability and its structural tunability by decorating or substituting either on its exterior surface or interior hollow cavity. For example, metal-decorated fullerene complexes have found important applications ranging from superconductivity, nanoscale electronic devices, and organic photovoltaic cells to catalysis and biomedicine. Compared to the large body of studies on atoms and molecules encapsulated by C60, studies on the exteriorly modified fullerenes, i.e., exohedral fullerenes, are scarcer. Surprisingly, to date, uncertainty exists about a fundamental question: what is the preferable exterior binding site of different kinds of single atoms on the C60 surface?In recent years, we have developed an experimental protocol to synthesize the desired fullerene-metal clusters and to record their infrared spectra via messenger-tagged infrared multiple photon dissociation spectroscopy. With complementary quantum chemical calculations and molecular dynamics simulations, we determined that the most probable binding site of a metal, specifically a vanadium cation, on C60 is above a pentagonal center in an η5 fashion. We explored the bonding nature between C60 and V+ and revealed that the high thermal stability of this cluster originates from large orbital and electrostatic interactions. Through comparing the measured infrared spectra of [C60-Metal]+ with the observational Spitzer data of several fullerene-rich planetary nebulae, we proposed that the complexes formed by fullerene and cosmically abundant metals, for example, iron, are promising carriers of astronomical unidentified spectroscopic features. This opens the door for a real consideration of Kroto's 30-year-old hypothesis that complexes involving cosmically abundant elements and C60 exhibit strong charge-transfer bands, similar to those of certain unidentified astrophysical spectroscopic features. We compiled a VibFullerene database and extracted a set of vibrational frequencies and intensities for fullerene derivatives to facilitate their potential detection by the James Webb Space Telescope. In addition, we showed that upon infrared irradiation C60V+ can efficiently catalyze water splitting to generate H2. This finding is attributed to the novel geometric-electronic effects of C60, acting as "hydrogen shuttle" and "electron sponge", which illustrates the important role of carbon-based supports in single-atom catalysts. Our work not only unveils the basic structures and bonding nature of fullerene-metal clusters but also elucidates their potential importance in astrophysics, astrochemistry, and catalysis, showing the multifaceted character of this class of clusters. More exciting and interesting aspects of the fullerene-metal clusters, such as ultrafast charge-transfer dynamics between fullerene and metal and their relevance to designing hybrid fullerene-metal junctions for electronic devices, are awaiting exploration.

Synthesis of bridged dinaphthoviologen derivatives for enhanced electrochromic performance and picric acid detection

Electrochromic materials represent a class of highly promising smart materials in contemporary research. Viologen, as a prevalent organic small molecule in smart chromic materials, has garnered extensive attention due to its tunable intermediate structure involving pyridine units and diverse nitrogen atom substituents. In this investigation, the molecular structure of dinaphthoviologen (DNV2+) were modified, and various groups were introduced to ionize nitrogen atoms. This structural modification aimed to decrease the molecular energy gap and enhance the electron acceptability of nitrogen atoms. The results demonstrate robust redox ability in DNV2+. To explore the practical applications, a straightforward DNV2+-based electrochromic device was fabricated, incorporating ferrocene as an electronic supplement. This device exhibited commendable cycling performance (exceeding 1000 cycles) and rapid response times (8 s for coloring and 10 s for fading) without the need for additional electrolytes. Additionally, the transmittance changes by more than 45 %. Moreover, owing to the presence of conjugated structures, DNV2+ exhibited noteworthy fluorescence properties. In fluorescence-based picric acid detection experiments, the synthesized molecules exhibited high selectivity and sensitivity, as evidenced by the determined Stern–Volmer constants (K6b = 2.17 × 104 L/mol, K6c = 3.87 × 104 L/mol). The findings highlight the potential of the developed dinaphthoviologen derivatives for advanced applications in electrochromic devices and sensitive detection of picric acid.

An ultra-photosensitive viologen-based hybrid crystalline material with unconventional transfer pathways

Viologen units are widely used in UV/X-ray detection, photoelectric detection, intelligent anti-counterfeiting, and inkless printing owing to their excellent photo-induced electron transfer (PET). In the previous research, the traditional electron transfer channel types of highly photosensitive viologen-based PET materials were mostly O/X … N (X=Cl, Br, I). In this work, we synthesized a photochromic 0-dimensional supramolecular, [Cd1.5(m-CBbpy)(Cl)4(DMA)]n (1). The electron transfer type of 1 is unconventional Cl⋯H–C, which has an ultra-sensitive response to UV and indoor light. (after 0.3 s under 135.2 mW cm−2 Xe lamp, UV absorption can reach 1/3 of the light saturation; after 20 min under indoor light, the color of 1 turned blue). This is because by introducing more Cl− as electron donors, the cyano group (–CN) on the m-CBbpy·Cl ligand enhances the electron acceptance ability, and the charge interaction formed by Cl− and m-CBbpy+ assists electron transfer (ET). In addition, 1 has amine chemochromism, electrochromism, and wide photocurrent response from 375 to 1850 nm. Therefore, 1 is an excellent material for light/amine/electrical stimulation response and a candidate material for photoelectric detection in the UV–Vis-SWIR region. And it provided clues for developing highly photosensitive viologen material.

Methane emissions and the microbial community in flooded paddies affected by the application of Fe-stabilized natural organic matter

Redox chemistry involving the quinone/phenol cycling of natural organic matter (NOM) is known to modulate microbial respiration. Complexation with metals or minerals can also affect NOM solubilization and stability. Inspired by these natural phenomena, a new soil amendment approach was suggested to effectively decrease methane emissions in flooded rice paddies. Structurally stable forms of NOM such as lignin and humic acids (HAs) were shown to decrease methane gas emissions in a vial experiment using different soil types and rice straw as a methanogenic substrate, and this inhibitory behavior was likely enhanced by ferric ion–NOM complexation. A mechanistic study using HAs revealed that complexation facilitated the slow release of the humic components. Interestingly, borohydride-based reduction, which transformed quinone moieties into phenols, caused the HAs to lose their inhibitory capacity, suggesting that the electron-accepting ability of HAs is vital for their inhibitory effect. In rice field tests, the humic–metal complexes were shown to successfully mitigate methane generation, while carbon dioxide emissions were relatively unchanged. Microbial community analysis of the rice fields by season revealed a decrease in specific cellulose-metabolizing and methanogenic genera associated with methane emissions. In contrast, the relative abundance of Thaumarchaeota and Actinomycetota, which are associated with NOM and recalcitrant organics, was higher in the presence of Fe-stabilized HAs. These microbial dynamics suggest that the slow release of humic components is effective in modulating the anoxic soil microbiome, possibly due to their electron-accepting ability. Given the simplicity, cost-effectiveness, and soil-friendly nature of complexation processes, Fe-stabilized NOM represents a promising approach for the mitigation of methane emissions from flooded rice paddies.

Highly electron-deficient 1-propyl-3,5-dinitropyridinium: evaluation of electron-accepting ability and application as an oxidative quencher for metal complexes.

Impacts of the nitro groups on the electron-accepting and oxidizing abilities of N-propylpyridinium were evaluated quantitatively. A 3,5-dinitro derivative has efficiently quenched emission from photosensitizing Ru(ii) and Ir(iii) complexes owing to the thermodynamically-favored electron transfer to the pyridinium whose LUMO is greatly lowered by the presence of electron-withdrawing nitro groups.

Synthesis and properties of bay-functionalized 9,9′-bifluorenylidene derivatives

Abstract Here, we disclose the effect of substitution at the bay-region of 9,9′-bifluorenylidene on its optical and electrochemical properties. Bay-brominated 9,9′-bifluorenylidene was synthesized by the reductive dimerization of 4,5-dibromofluorenone with triethyl phosphite. The subsequent Suzuki–Miyaura cross-coupling afforded arylated derivatives. X-ray diffraction analysis revealed that the bulky bay-substituents twist the overall structure through the relay of the steric repulsion from the bay-region to the fjord-region. The π-extension at the bay-region with tolyl and 4-dimethylaminophenyl groups increases the electron-donating ability, while the introduction of bromo groups enhances the electron-accepting ability.

A convenient strategy to develop sp2 hybridized fused Y123 monomers for photovoltaic and optical ON-OFF switches with economic energy offsets

This paper presents a design strategy, their efficient visible light converting optimizations offsets and dye anchorage utility as N-doped fused ring electron acceptors of organic dye Y123 in photovoltaic and optical devices. Five novel dyes (Y1–Y5) are investigated, identifying major electronic contributions. Results shows favourable energy levels and oscillator strengths (f) for efficient charge transfer upon photoexcitation. The dye Y1 had an ionization potential (IP) of 3.00eV, electron affinity (EA) of 1.01eV, and dipole moment of 2.01D. The dye Y3 exhibited a high global hardness (η) of 0.85 and low softness (σ) of 0.12eV, indicating stability and strong electron-accepting ability. Evaluation of photovoltaic performance revealed impressive characteristics, such as Y2 with a light harvesting efficiency (LHE) of 98 %, open-circuit voltage of 1.74eV, fill factor of 0.9235, and short-circuit current (Jsc) density of 50.92 mA/cm2, resulting in a maximum power output (Pmax) of 81.82W. This study also included a detailed analysis of transition density matrix (TDM) and electron-hole overlap, providing insights into exciton dissociation and charge separation mechanisms in Y123 dyes. These analyses enhance the design of efficient N-doped fused ring electron acceptors for organic photovoltaic and optical devices. The study demonstrates the potential of N-doped fused ring electron acceptors as promising materials for efficient energy conversion in next-generation organic photovoltaic and optical devices.

Chitosan-cellulose composite for the adsorptive removal of anionic dyes: Experimental and theoretically approach

The chitosan-cellulose composite was prepared and employed for the adsorptive removal of Reactive Red 195 (RR195) and Reactive Red 2 (RR2) dyes. The cellulose was extracted from bagasse and then, chitosan composite was prepared by solution casting method. The adsorption dependent parameters were optimized, i.e., pH, dyes initial concentration, temperature and reaction time. At room temperature, the dyes adsorption efficiencies were 71.5 % and 97.16 % for RR2 and RR195 at pH 4 and 2, respectively. Point of zero charge found to be at 6 pH for the composite. Both dyes adsorptions data followed pseudo second order kinetics model. The RR195 dye adsorption was best explained by Langmuir isotherm model and in case of RR2 dye, the Freundlich isotherm fitted well. The characterization of the prepared composite was performed by Fourier Transform Infrared Spectroscopic analysis. In Density Functional Theory (DFT) studies, the LUMO, total energy (HF) and adsorption energies (Eads) were found to be −3.73 eV, −8413.210HF and −25.46Kcal, respectively in case of RR195 dye, while these values were −3.67 eV, −5859.036 HF, −20.69Kcal for RR2, which revealed that RR195 has the higher electron-accepting ability and reactive toward chitosan-cellulose composite. The findings revealed that the chitosan-cellulose composite have promising adsorptive efficiency and could be employed for the removal of dyes from effluents.