Scientific Research Communications

Novel Fullerene-Based Dyes for Solar Cells Applications: Insights from Density Functional Theory and Time Dependent Density Functional Theory Investigations

Ismail Muhammad — 2025-01-24

Fullerene-based organic dyes hold significant promise for advancing solar cell technologies due to their exceptional optoelectronic properties. This study investigates two novel fullerene-based dyes, Fullerene Dye 1 and Fullerene Dye 2 (FD1 and FD2), using Density Functional Theory (DFT) and Time-Dependent Density Functional Theory (TD-DFT) to evaluate their potential for solar cell applications. The electronic properties, including the Highest Occupied Molecular Orbital (HOMO), Lowest Unoccupied Molecular Orbital (LUMO), and HOMO-LUMO (H-L) energy gaps, were analyzed using the B3LYP functional with a 6-31G basis set, incorporating solvation effects with dichloromethane (DCM) in the Polarizable Continuum Model (PCM). FD1 exhibited a HOMO of -5.123 eV, a LUMO of -3.458 eV, and an H-L gap of 1.665 eV, while FD2 showed a slightly larger gap of 1.807 eV with a HOMO of -5.261 eV and a LUMO of -3.454 eV. Time-dependent DFT analysis revealed maximum absorption wavelengths (\lambda max) of 997.10 nm and 995.16 nm for FD1 and FD2, respectively, with corresponding oscillator strengths of 0.0075 and 0.0048. The light-harvesting efficiencies, LHEs of FD1 and FD2 were 0.018 and 0.012, respectively. Both dyes demonstrated favorable reorganization energy, \lambda=0.15eV, driving force for charge injection, \Delta G_inj = 0.542eV for FD1 and 0.546 eV for FD2, and low driving force for charge recombination (\Delta G_CR), indicating strong potential for efficient charge separation. These findings provide valuable insights into the electronic, optical, and charge transfer properties of fullerene-based dyes, with FD1 exhibiting a more balanced performance. The study highlights the potential of these dyes for enhancing the efficiencies of organic, dye-sensitized solar cells (DSSCs) and provides a foundation for future experimental validation and optimization.

A Note On The Dirichlet-Neumann Problem in The Upper Half Unit Disc

Bahriye Karaca — 2025-01-31

This study addresses the solvability and explicit solutions of various boundary value problems (BVPs) for inhomogeneous equations within the upper half unit disc. Specifically, we investigate the Dirichlet, Neumann, and mixed Dirichlet-Neumann problems for the inhomogeneous Cauchy-Riemann and Bitsadze equations. By employing analytical techniques and function space theory, we establish necessary and sufficient conditions for the existence of solutions. Furthermore, explicit solution formulas are derived under these solvability criteria, providing a constructive approach to solving such BVPs. The significance of this research lies in its contribution to the broader theory of BVPs in complex domains. The results obtained not only extend classical boundary conditions but also offer a systematic framework for dealing with higher-order equations. The interplay between different boundary conditions is explored in detail, revealing new insights into the structure of solutions and their dependence on boundary data. Beyond the theoretical implications, our findings have potential applications in mathematical physics, fluid dynamics, and engineering, where such problems frequently arise in modeling physical phenomena. Future research may further extend these results to more general domains and nonlinear equations, enriching the field of complex analysis and partial differential equations.

Solution of the Single Degree of Freedom System Using Bernoulli Collocation Method

Kubra Erdem Bicer — 2025-01-24

The fundamental subject of a single degree of freedom system's free vibration is essential in the field of mechanical vibrations, with applications in a wide range of engineering fields. This paper presents a novel numerical method for solving this problem based on Bernoulli polynomials in matrix form. The method is simple to implement and requires only basic linear algebra operations. The method is also very efficient; and can be used to solve problems with the single degree of freedom system. The proposed method is illustrated by a numerical example, and the results are compared with those of the exact solution. The results show that the proposed method is highly accurate and efficient.

New Amperometric Glucose Biosensors Based On Nafion Nanofibers

Sawssen Ghannouchi — 2025-01-24

In this study, we present new amperometric glucose biosensors based on Nafion nanofibers. Nafion possesses a number of desirable properties, including stability, thermal, mechanical, physio-chemical and biocompatibility, which make it a competitive polymer for use in glucose biosensors. Nafion nanofibers were produced using a low-cost electrospinning method, and their morphology was characterized via scanning electron microscopy (SEM). The biosensors were fabricated by loading glucose oxidase (GOx) and GOx-AuNPs (10 nm) on the Nafion-Cellulose Acetate nanofibers (Nafion-CA Nfs) (461.53 ± 30.34 nm) on the surface of a platinum electrode, followed by cross-linking using glutaraldehyde. The biosensors operating at 0.6 V demonstrated lower LODs with wider linear ranges, enhanced stability, elevated sensitivity, and improved selectivity. For Pt/Nafion-CA NFs/GOx biosensor demonstrated remarkable sensitivity, with values of 68.67 \mu A.mM-1cm-² and 18.38 \mu A.mM-1.cm-², respectively, and a limit of detection (LOD) of 1.36 \mu M. Meanwhile, the Pt/Nafion-CA NFs/ GOx-AuNPs biosensor achieved sensitivities of 55.56 \mu A.mM-1.cm² and 28.49 \mu A/mM·cm², respectively. It also exhibited a broad linear range of up to 12.81 mM and an LOD of 10.8 \mu M, with no observable interference effects. The present studies highlight the potential of Nafion nanofibers as a suitable matrix for immobilizing GOx and GOx-AuNPs, thereby demonstrating their viability as interference-free, easy-to-use sensors with good sensitivity, LOD and stability for commercialization.

An Analysis of a Historical House in Alaçati, Çesme

Burcu Tasci — 2025-01-24

Alaçat?, located on the Çe?me Peninsula in Türkiye, is a historic and touristic coastal settlement. In recent years, despite the growing influence of tourism on its historic center, the settlement has managed to partially preserve its urban fabric and architectural heritage. In the historic center of the settlement, the civil architecture from the Ottoman period stands out as a prominent physical representation of cultural heritage. Historical houses are particularly significant for understanding the socio-cultural history of the settlement. Today, most of them have been restored and lost their original functions. On the other hand, some historical buildings hold a significant place in the city's memory, not only for their residential function but also for their commercial role in the settlement. A notable example is a two-storied stone house named “Yürük Grocery”, situated in the Hac? Memi? Neighborhood, Alaçat?. Among the other historical houses, it stands out with its corner position, shared courtyard design and ground-floor function. This study aims to document the architectural features and cultural heritage values of this historical building, trace its evolution over time, and contribute to the literature. The methodology of this study includes documentation, literature review, archival research, fieldwork, and oral expressions. As a result, this study has identified three periods by examining the building's architectural features, history, construction techniques, and material characteristics in its evolution. In this way, the study contributes to maintain its historical identity.