Electronic Structure Analysis Research Articles

Rational Design of Novel Single-Atom Catalysts of Transition-Metal-Doped 2D AlN Monolayer as Highly Effective Electrocatalysts for Nitrogen Reduction Reaction

The single-atom catalysts (SACs) for the electrocatalytic nitrogen reduction reaction (NRR) have garnered significant attention in recent years. The NRR is regarded as a milder and greener approach to ammonia synthesis. The pursuit of highly efficient and selective electrocatalysts for the NRR continues to garner substantial interest, yet it poses a significant challenge. In this study, we employed density functional theory calculations to investigate the stability and catalytic activity of 29 transition metal atoms loaded on the two-dimensional (2D) AlN monolayer with Al monovacancy (TM@AlN) for the conversion of N2 to NH3. After screening the activity and selectivity of NRR, it was found that Os@AlN exhibited the highest activity for NRR with a very low limiting potential of −0.46 V along the distal pathway. The analysis of the related electronic structure, Bader charge, electron localization function, and PDOS revealed the origin of NRR activity from the perspective of energy and electronic properties. The high activity and selectivity towards the NRR of SACs are closely associated with the Os-3N coordination. Our findings have expanded the scope of designing innovative high-efficiency SACs for NRR.

Emergent local negative electrostriction induced by oxygen vacancy in BaHfO3: Defect engineering

Realization of ultrasmall scale electromechanical materials has been promising for advanced functional devices. Recently, single-atom devices have been proposed as the ultimate miniaturization of functional devices beyond the nanoscale; however, achieving an atomic-scale local electromechanical response is still challenging due to physical size limitation of electromechanical properties as well as technical difficulties in fabricating the functional materials in a single atom precision. Here, we demonstrate a non-trivial negative electromechanical response at an oxygen vacancy in paraelectric BaHfO3 using first-principles finite electric field calculations. We find an electrostrictive response at the vacancy site in the same order of magnitude in well-known oxide materials. Surprisingly, we also discover an unusual “negative” sign of electrostriction in the oxygen vacancy. The detailed electronic structure analysis demonstrates that a unique electric field response of a localized defect electronic structure is the origin of this negative electrostriction of vacancy. The present results provide an important implication for the design of ultra-small electromechanical functions at an atomic scale.

Role of solute elements in Mg-Mg2Ni hydrogen storage alloys: A first-principles calculation study

The effects of various alloying elements on the performance of Mg-Mg2Ni hydrogen storage alloys were investigated by performing first-principles density functional theory calculations. We examined the important characteristics of hydrogen storage alloys by considering both Mg-based solid solution and Mg2Ni-based intermetallic compound phases, where the hydride forms are MgH2 and Mg2NiH4, respectively. In particular, qualitatively valid information for predicting changes in plateau pressures in the pressure-composition-temperature (PCT) curve was provided by calculating changes in the energy of related hydrogenation reactions. The effects of alloying elements on volume changes due to hydrogenation reactions were also obtained to provide additional criteria for the practical use of hydrogen storage alloys. For the Mg2Ni-based intermetallic compound, we examined the site preference of each alloying element, considering the designated stoichiometry of the base alloy. Based on the revealed site preferences, the effects of various possible alloying elements on the properties of Mg2Ni-based hydrides were also examined. Electronic structure analyses were further conducted to elucidate the detailed mechanisms underlying the role of the additional solute elements.

Near-Field Coupling Resonance Enhancement with AuNiO Heterostructure Nanosheets For High-performance Photodynamic/Photothermal Hybrid Antibacterial & Imaging Tracking

Bacterial infection has always been a serious public health problem worldwide. Real-time microbial monitoring in the trauma resuscitation unit is crucial for infection control and plays an essential role in all aspects of wound treatment clinical practice, such as identification and evaluation of wound infection, diagnosis of wound infection, and topical antimicrobial treatment. Herein, gold-loaded nickel oxide nanosheets (Au-NiO NSs) prepared by hydrothermal and laser-assisted synthesis methods are used as fluorescent nanoprobes to rapidly detect and target bacteria at an early stage, and then achieve combined PTT and PDT to inactivate bacteria under sunlight. Optical detection, electronic structure and plasma local field analysis show that there is charge transfer between Au10-O-NiO through the O-Au-O bond, and effectively improves the plasmon effect through resonant energy transfer, achieving higher photothermal conversion efficiency. The detection limits of Staphylococcus aureus and Pseudomonas aeruginosa are as low as 145.6 and 157.7 cfu/mL, respectively, and the sterilization rates are both above 99%. In addition, Au-NiO NSs have low cytotoxicity, and the nanocomposite dressing prepared by combining Au−NiO NSs with hydrogels demonstrates the ability to monitor and kill pathogens in situ in the treatment of skin wounds. The platform integrates the targeting, imaging and inactivation capabilities of bacteria, showing great application potential in the field of bacterial diagnosis and treatment.

Unveiling activity of transition metal single-atom sites on the graphene-like BC2P monolayer for oxygen evolution reaction: A density functional theory study

The electrocatalytic oxygen evolution reaction (OER) represents a pivotal process at the cathode of next-generation electrochemical storage and conversion technologies, among of them, OERs incorporating a single transition metal (TM) atom exhibit considerable potential for supplanting noble metals as electrochemical catalysts for fuel cells and metal-air batteries. Therefore, in this paper, we elucidated impacts of the TM monoatomic sites on the catalytic activity of OER on graphene-like BC2P monolayer through the utilization of density functional theory (DFT) calculations. Analysis of electronic structure reveals that the hybridised antibonding orbitals formed by the TM-3d and O-2p orbitals possess low-energy and high-occupancy properties, which weaken the OH-TM interactions and thus affect the catalytic activity of TM-N3 active site. Among all considered active sites, the Ni-N3 and Cu-N3 sites exhibited the most favourable OER catalytic performance, with the OER overpotential of the Ni-N3 site being only 0.42 eV, indicating an extremely high level of catalytic efficiency. Additionally, by exploring the coordination environment around the TM atoms, our study proposed a macroscopic descriptor and established a linear relationship between the catalytic performance and the descriptor using the linear regression. Therefore, our work offered theoretical guidance for the design of new and efficient OER catalysts, and further established a link between the microscopic mechanism of action and the macroscopic performance of catalysts, which providing new ideas for the development of high-performance catalytic materials.

First-principles study of Y, Ca microalloyed Mg-Zn alloy

This article investigates the complex effects of Y and Ca alloying on the G.P. zones ( parallel to {0001}Mg)and G.P.1 zones ( parallel to {2-1-10}Mg) in Mg-Zn alloys, as well as their corresponding changes in thermal stability, electronic structure, and mechanical properties, using first-principles calculations. The addition of Y significantly enhances the thermal stability of both the G.P. and G.P.1 zones, whereas the effect of Ca is more limited, mainly enhancing the thermal stability of the one-atomic layer G.P. zones, but possibly decreasing the thermal stability in other areas. In the combined alloying of Y and Ca, the cooperative effect optimizes the thermal stability of the one-atomic layer and half-atomic layer G.P.1 zones, but reduces the thermal stability of other G.P. zones. Through studying the local density of states and the atomic radial distribution function, it is revealed that the higher stability of the half-atomic layer G.P. zones compared to the one-atomic layer G.P. zones is due to more Mg-Zn and Mg-Mg bonds, whereas the one-atomic layer G.P.1 zones exhibits higher stability because of shorter and more stable Zn-Zn, Mg-Zn, and Zn-Mg bonds. The electronic structure analysis shows that Y mainly appears in the alloy in the form of electron localization, readily forming ionic bonds with Mg and Zn, which is a key reason for its effective alloying results. In contrast, Ca, as well as the alloying of Y and Ca, do not form effective bonds on the energy levels from -8eV to -5eV, explaining their weaker alloying effects. Additionally, the study of mechanical properties indicates that the G.P. zones of pure Zn, due to its significant difference in shear modulus from the magnesium matrix, is not easily strengthened by dislocation shearing and thus mainly strengthened through the Orowan mechanism. The addition of Y significantly increases the strength and hardness of the one-atomic layer G.P. zones, but decreases the ductility. The addition of Ca changes the anisotropy of the Young's modulus of the one-atomic layer G.P. zones, while the combined effect of Y and Ca greatly alters the anisotropy of the shear modulus of this phase. These findings provide important theoretical guidance and insights for the design and application of Mg-Zn alloys.

The structural, elastic, optoelectronic properties and hydrogen storage capability of lead-free hydrides XZrH3 (X: Mg/Ca/Sr/Ba) for hydrogen storage application: A DFT study

Perovskite hydrides are promising materials for hydrogen capacity application to achieve the US DOE on-board criteria. We have investigated novel perovskite hydrides XZrH3 (X: Mg/Ca/Sr/Ba) for H2 storage and transportation applications. In this study we investigates the physical properties of XZrH3 light materials for solid-state hydrogen storage application by incorporating the DFT framework with the CASTEP code. We have theoretically examined the structural, mechanical, electronic, optical, and hydrogen storage properties of these materials. The selected compounds were fully relaxed and optimized in the cubic phase space group Pm-3 m. Structural phase stability was confirmed through thermodynamic, and mechanical analyses. Mechanical properties, evaluated based on Poisson’s ratio, the Puagh’s ratio, and Cauchy pressure, indicate the ductile behavior with a preference for ionic bonding. The electronic structure analysis reveals the metallic behavior of these materials. Optical calculations were also performed to provide additional insights into the physical properties of H2 compounds. The gravimetric hydrogen storage capacities were calculated as 2.55, 2.25, 1.66, and 1.31 wt% for MgZrH3, CaZrH3, SrZrH3, And BaZrH3 hydrides respectively. The identified properties of XZrH3 suggest that these materials could significantly enhance hydrogen storage systems, with potential integration into existing energy technologies, offering a pathway toward more efficient and sustainable hydrogen-based solutions.

First-principles study of the electronic, vibrational, thermodynamic properties and phase stability of orthorhombic KClO4 under pressure

The purpose of this study is to deeply understand the basic physical properties of potassium perchlorate (KClO4) as a typical ionic energetic material under pressure. KClO4 Received attention for its widespread use in explosives, fireworks, safety matches and rocket propellants. In this paper, we systematically study the basic physical properties of KClO4 under 0-20 GPa pressure, including electrons, mechanical, vibrations, and thermodynamic parameters, based on density functional theory (DFT). The accuracy of the calculations was verified by optimizing the lattice parameters of the crystal structure and comparing them with previous experimental values. Electronic structure analysis revealed that KClO4 is a broadband gap nonconductor. Electronic density of states (DOS) analysis revealed strong covalent bonding between Cl-O bonds. Based on the phonon information, this study calculates the thermodynamic properties of KClO4 and analyzes a function of the relevant thermodynamic quantities under pressure. Combined with the structural phase transition phenomena observed in high pressure experiments, we analyze the dynamic and mechanical instability. These analyses help to understand the behavior of KClO4 under high pressure conditions and are crucial for its application in energetic materials.

Synthesis, Structural Characterization, and Electronic Structure Analysis of F2-type Superatomic Molecules.

The investigation of bonding interactions between superatoms continues to be a largely unexplored area of study. In this study, we present the synthesis and characterization of two F2-type superatomic molecules [Au2Ag25(C7H4NOS)13(DPPB)3] and [Au9Ag18(C5H4NS)11(DPPM)5]2+ (Au2Ag25 and Au9Ag18 for short, respectively). The overall structures were confirmed via X-ray crystallography, revealing the horizontal expansion of the biicosahedral Au2Ag21 yielding [Au2Ag25(C7H4NOS)13(DPPB)3] and vertical expansion of the biicosahedral Au8Ag15 yielding [Au9Ag18(C5H4NS)11(DPPM)5]2+. Furthermore, their electronic structures were elucidated through density functional theory (DFT) calculations. Spectroscopic analysis of electronic absorption characteristics, in conjunction with Tamm-Dancoff approximation DFT (TDA-DFT) calculations, revealed that the Au2Ag21(+9) and Au8Ag15(+9) cores were analogues of the F2 molecule in electronic configuration.

A First‐Principles Study of Manganese‐Based Perovskite‐Type Hydrides for Hydrogen Storage Application

Herein, a series of perovskite‐type hydride materials RMnH3 (R = Ca, Sr, and Ba) are investigated by density functional theory for solid‐state hydrogen storage. Their structural, mechanical, electronic, and optical properties are calculated and their thermodynamic, dynamic, and mechanical stability is assessed. All compounds crystallize in the undistorted cubic perovskite system with the Pm‐3m symmetry. The results from mechanical properties, based on parameters such as Poisson's ratio (ν) and the G/B ratio, indicate that CaMnH3 and SrMnH3 exhibit brittle behavior, primarily attributed to the dominance of ionic bonds, while BaMnH3 is distinguished by its ductility, resulting from a prevalence of covalent bonds. Additionally, the electronic structure analysis reveals that all examined hydrides possess metallic behavior. Further calculations of the optical properties are also performed, providing supplementary insights into the physical features of the hydrides. The gravimetric hydrogen storage capacities (Cwt%) are calculated, with values of 2.96 wt% for CaMnH3, 2.019 wt% for SrMnH3, and 1.513 wt% for BaMnH3, accompanied by respective desorption temperatures of 214.83, 193.42, and 145.43 K. Overall, these results highlight the potential of perovskite hydrides RMnH3 as promising materials for hydrogen storage applications, significantly contributing to a sustainable energy future.

From a P-Bridging Phosphaketene to μ-Phosphinidenide and μ-Diphosphaurea Units at a Dinickel Core.

Salt metathesis of dinickel(II) complex LNi2Br (1; L is a dinucleating pyrazolate ligand with two β-diketiminato chelate arms) with Na(OCP)∙(dioxane)2.5 yielded LNi2(PCO) (2) with a P-bridging phosphaethynolate. Further reaction of 2 with benzyl isocyanide or with an N-heterocyclic carbene (NHC) triggered decarbonylation and gave LNi2(PCN-CH2Ph) (3) and LNi2P(NHC) (4) with P-bridging cyanophosphide and NHC-phosphinidenide, respectively. Electronic structure analysis indicated a μ2-η2:η1 binding mode of the PCO- anion between the two NiII ions in 2, which is even more pronounced for the [PCN(-CH2Ph)]- anion in 3. DFT assessment of the formation mechanism of 4 showed that attack at the phosphaketene-C atom is kinetically preferred but reversible and unproductive, while kinetically more demanding back-side SN2 attack at the phosphaketene-P atom triggers CO release with 4 as thermodynamic product. Nucleophilic addition at the phosphaketene-C could be demonstrated by the strongly exergonic reaction of 2 with KPPh2, giving unstable K[LNi2(P(O)CPPh2)] (5) with a P-bridging and K+-stabilized diphosphaurea derivative. All new complexes 2-5 have been comprehensively characterized, including by X-ray diffraction.

Structural properties, thermodynamic stability and reaction pathways for solid-state synthesis of Bi2WO6 polymorphs.

This study presents a density functional theory (DFT) investigation into the structural, electronic, and optical properties, thermodynamic stability, phase competition, and reaction pathways of Bi2WO6, a notable compound within the Aurivillius family of oxides. We examine three distinct polymorphs of Bi2WO6: the low-temperature orthorhombic phase (P1), the intermediate-temperature orthorhombic phase (P2), and the high-temperature monoclinic phase (P3). Electronic structure analysis indicates band gaps of 2.339 eV (P1), 2.312 eV (P2), and 2.128 eV (P3), with the valence band primarily composed of O 2p states and the conduction band of Bi 6p and W 5d states. Optical properties, including the dielectric function and absorption spectra, show distinct behaviors for each phase, particularly P3. Elastic and phonon property analyses confirm the mechanical and dynamical stability of all three phases, with the P1 phase exhibiting the highest bulk modulus and stiffness among the polymorphs. Our effective mass calculations suggest that the P3 phase may have better charge carrier mobility compared to the P1 and P2 phases. Structural optimizations reveal marginal differences in total energy among these phases, suggesting their potential coexistence or easy phase transitions under varying conditions. Detailed Gibbs free energy calculations confirm that the P1 phase is the most stable at low temperatures, in agreement with experimental data in the literature. We also construct a chemical reaction network to explore feasible reaction pathways for the solid-state synthesis of Bi2WO6 from Bi2O3 and WO3 precursors, identifying several low-cost reaction pathways, including both direct and multi-step routes involving intermediates such as Bi14WO24 and Bi2W2O9.

Two-dimensional boron nitride allotrope Irida-B12N12 with 3-6-8 membered rings and wide-bandgap semiconducting properties

We present a novel two-dimensional (2D) boron nitride allotrope, Irida-B12\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\hbox {B}_{{12}}$$\\end{document}N12\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\hbox {N}_{{12}}$$\\end{document} (Ir-BN), analogous to the all-carbon Irida-Graphene (Ir-G). The predicted structure of Ir-BN consists of alternating boron and nitrogen atoms, forming three distinct lattices with 3-, 6-, and 8-membered ring patterns. First-principles calculations based on density functional theory (DFT) formalism and ab initio molecular dynamics (AIMD) simulations were performed to investigate its structural, mechanical, electronic, and optical properties. The Ir-BN lattices exhibit good dynamical and thermal stability, supporting their viability as new 2D materials. Substantial anisotropy is observed in the mechanical properties, with in-plane stiffness ranging from 16 to 142 N/m, depending on the direction, and bulk moduli between 78 and 95 N/m. The electronic structure analysis reveals that Ir-BN is a wide-bandgap semiconductor, with band gaps ranging from 2.4 to 3.2 eV. The material shows optical activity particularly in the visible and ultraviolet regions.

Single-atomic iron synergistic atom-cluster induce remote enhancement toward oxygen reduction reaction

The oxygen reduction reaction (ORR) could be effectively regulated by adjusting electron configurations and optimizing chemical bonds. Herein, we have achieved the modulation of electron distribution in Fe single atomic (FeSA) sites through Fe atomic clusters (FeAC) via a confined pyrolysis approach, thereby enhancing their intrinsic ORR activity. X-ray absorption spectroscopy has confirmed that the presence of iron atomic clusters could influence the electron distribution at Fe-N4 sites. The FeSA/FeAC-NC catalyst exhibits a half-wave potential of 0.88 V, surpassing the individual FeSA-NC structure. Through electronic structure analysis, it could be seen that iron atom clusters can affect Fe-N4 sites through long-range effects, and then effectively lower reaction barriers and enhance the reaction kinetics at Fe-N4 sites. The synthetic approach might pave the way for constructing highly active catalysts with tunable atomic structures, representing an effective and universal technique for electron modulation in M-N-C systems. This work provides enlightenment for the exploration of more efficient single-atom electrocatalysts and the optimization of the performance of atomic electrocatalysts. Furthermore, a zinc-air battery assembled using it on their cathode deliver a high peak power density (205.7 mW cm−2) and a high-specific capacity of 807.5 mA h g−1. This study offers a fresh approach to effectively enhance the synergistic interaction of between Fe single atom and Fe atomic clusters for improving ORR activity and energy storage.

Ambipolar Charging Responses of Nanoscale Interfaces.

Low-dimensional sp2-based carbon nanostructures, known for their remarkable transport properties and mechanical behaviors, are widely used as reinforcing phases in polymer composites to enhance their performance. While carbon nanocomposites are promising materials for extreme conditions, the damage mechanisms due to charge injection at the interfaces between carbon nanostructures and polymers remain unclear. Using first-principles calculations, we investigated ambipolar charging and structural responses at the interfaces between industrially relevant polymers and carbon nanotubes or graphene upon electron and hole injection. Our electronic structure analysis reveals that resistance to charge injection is closely related to the band structures of the polymers and the chemistry of interfacial cross-links. Mechanical behaviors assessed through traction and shear tests reflect changes in electronic coupling at the interfaces. Our results indicate significantly degraded mechanical performance with electron injection, while slight hole injection leads to shortening and stiffening of covalent bonds. These findings provide crucial insights for the design of carbon nanocomposites intended for harsh environments, such as lightning strikes and high-power electromagnetic shocks.

Specific Adsorption of Alkaline Cations Enhances CO-CO Coupling in CO2 Electroreduction.

Electrolyte alkaline cations can significantly modulate the reaction selectivity of electrochemical CO2 reduction (eCO2R), enhancing the yield of the valuable multicarbon (C2+) chemical feedstocks. However, the mechanism underlying this cation effect on the C-C coupling remains unclear. Herein, by performing constant-potential AIMD simulations, we studied the dynamic behavior of interfacial K+ ions over Cu surfaces during C-C coupling and the origin of the cation effect. We showed that the specific adsorption of K+ readily occurs at the surface sites adjacent to the *CO intermediates on the Cu surfaces. Furthermore, this specific adsorption of K+ during *CO-*CO coupling is more important than quasi-specific adsorption for enhancing coupling kinetics, reducing the coupling barriers by approximately 0.20 eV. Electronic structure analysis revealed that charge redistribution occurs between the specifically adsorbed K+, *CO, and Cu sites, and this can account for the reduced barriers. In addition, we identified excellent *CO-*CO coupling selectivity on Cu(100) with K+ ions. Experimental results show that suppressing surface K+-specific adsorption using the surfactant cetyltrimethylammonium bromide (CTAB) significantly decreases the Faradaic efficiency for C2 products from 41.1% to 4.3%, consistent with our computational findings. This study provides crucial insights for improving the selectivity toward C2+ products by rationally tuning interfacial cation adsorption during eCO2R. Specifically, C-C coupling can be enhanced by promoting K+-specific adsorption, for example, by confining K+ within a coated layer or using pulsed negative potentials.

Unveiling the mechanistic landscape and advantages of two-dimensional phthalocyanine in sustainable urea synthesis

This article presents a novel and innovative approach to address the challenges of carbon fixation and wastewater treatment by directly synthesizing urea from carbon dioxide and nitrate ions using electrocatalytic C-N coupling technology. The key scientific questions addressed in this study include the role of CO2 in the urea synthesis, and the existence of alternative reaction mechanisms involved in urea synthesis. To answer these questions, a systematic research framework is established, utilizing two-dimensional porphyrin-based bi-atom (M2-Pc) catalysts as models, conducting mechanism investigation at the neutral condition (pH =7). The electronic structural analysis, thermodynamic and kinetic calculations provide valuable insights into the reaction mechanisms involved in direct CO2-NO coupling and offer guidance for the design of more efficient catalytic systems for electrochemical urea synthesis. This research contributes to advancing our knowledge in the field of electrochemical urea synthesis and provides some insightful guidance for future studies.

First principles investigations on structural, electronic, optical, and thermodynamical properties of bulk and surfaces of In2CO

This study reports first-principles investigations of the structural, electronic, thermal, and optical properties of a novel material In2CO in bulk phase and slab models in (001), (100), (101), and (011) orientations to develop a fundamental understanding of its characteristics. The material appeared structurally as well as dynamically stable in the orthorhombic phase. The thermal properties demonstrated that the material's heat capacity is more temperature-sensitive than entropy and enthalpy. The electronic band structure analysis revealed that the orthorhombic phase material is a semiconductor with a narrow indirect band gap. The electronic structures modeled using the spin-orbit coupling yielded the metallic phase of the slabs except for (001) orientation. The electromagnetic absorption characteristics of the compound are also investigated to explore the material's potential in optoelectronic applications. The direction-dependent study of optical characteristics revealed that the (001) slab of the material can be an efficient infrared detector. The survey findings provide instrumental outcomes in utilizing In2CO in electronic and optoelectronic applications.

The non-covalent interaction between C3N and H2

Non-covalent interactions play an important role in numerous fields, particularly in physical hydrogen storage. The hydrogen storage properties of C3N are investigated by DFT calculations. The results indicated that H2 and C3N form physical adsorption. The electronic structure analysis demonstrates that both the covalent and electrostatic interactions between H2 and C3N are rather weak, while IRI analysis reveals that their interactions belong to non-valent interactions, and the further energy decomposition based on SAPT suggests that the sources of interaction energies differ for the two configurations TCR and TNR. For TCR, the induction energy is the primary contributor, for TNR, the electrostatic interaction dominates. Our comprehensive study not only enhances our understanding of the intricate interactions between H2 and C3N but also serves as a valuable guide for enhancing the adsorption strength in physical hydrogen storage systems.

Organic BODIPY based gels: Optical, electrochemical and self-assembly properties.

Two novel BODIPY dyes, BOC3 and BC12, were synthesized with variable alkyl chains at terminal amide functional units. BC12, featuring a longer alkyl chain (-C12H25), formed a gel compared to BOC3, which has a shorter alkyl chain (-CH2OCH3), due to supra molecular self-assembly in film. Both dyes exhibited absorption peaks around 530 nm in the visible region, with a red shift of about 30 nm in the film state, essential for organic electronic applications. Concentration variation studies revealed π-π stacking/aggregates in the solid state causing red shifts in absorption and emission. BC12 exhibited more significant red shifts in film compared to its solution state due to supra molecular self-assembly. Electronic structure analysis using density functional theories (BMK and O3LYP) showed better correlation with absorption using the O3LYP method. Both dyes displayed quasi-irreversible oxidation and reduction couples with suitable HOMO (5.46 eV) and LUMO (3.32 eV) energy levels for organic electronic applications. Transient photoluminescence studies indicated a longer lifetime for BC12 (5.28 ns) than BOC3 (4.50 ns), suggesting π-π aggregation and supra molecular self-assembly. BC12's gelation, attributed to its long alkyl chain and two-dimensional motifs of the BODIPY core, forms spherical-shaped nano networks.