Journal of Physical & Chemical Research

The effect of In, Cu Co-doping on the electronic structure and optical properties of ZnS. First principal calculations

2025-03-08T14:45:42+00:00

The effects of In and Cu co-doping ZnS on the structural, electronic and optical properties are investigated by using the full-potential linearized augmented plane wave method (FP-LAPW) with generalized gradient approximation plus Becke–Johnson potential as exchange-correlation potential, in a cubic structure. The calculated lattice parameter of Un-doped ZnS was in a good argument with the other theoretical calculations, and it was found to be increased by In, Cu co-doping. The electronic band structures are calculated and represented. The un-doped ZnS shows a semiconductor character with a direct band gap. Hence, it saves the semiconductor character with a direct band gap with some change in its value. It decreases by co-doping with In and Cu. Moreover, the real and imaginary part of the dielectric function as and the absorption coefficient attains its maximum in the near UV-Visible region. This theoretical study intensifies the understanding of the novel performances of In, Cu co-doped ZnS for optoelectronic applications.

A valorization of agricultural waste for the preparation of an environmentally sustainable material

2025-03-06T12:22:28+00:00

The valorization of agricultural waste is a critical area of research aimed at transforming what is often considered waste into valuable eco-friendly materials. This study has two objectives: firstly, to design a composite material based on a thermoplastic matrix (PVC) reinforced with vegetable fibres, which is chemically treated with acetic anhydride to improve the fibre-matrix interface. Secondly, to study the effect of this treatment on the physico-mechanical properties of resulting materials. The composites developed have been characterized by various analysis techniques, namely: tensile, hardness, water uptake and density tests. The recorded results show that increasing the load rate of the chemically treated fibre tends to decrease the elongation and breaking stress of the composites and increase their hardness and stiffness.

Adsorption of humic acid from aqueous solutions on organo Mg-Fe-SDS

2025-03-03T10:19:44+00:00

In this study, Organophilic LDH was prepared by interposing a surfactant (sodium dodecylsulfate, SDS 0.1 M) and applied for the removal of humic acid from solutions in batch system, the synthesized adsorbent (Mg-Fe-SDS) was characterized by FTIR, X-ray diffraction, and BET. Several adsorption kinetics models (pseudo-first order, pseudo-second order, n^th-order and intraparticule diffusion) were tested against the experimental results. The calculation of the corresponding parameters show that results are best fitted with n^th-order (n €R⁺), n≠1model with a determination coefficient close to 1 and a relatively small root mean square error. Among the available mathematical models used to describe the isotherms experimental results (Langmuir, Freundlich and many-parameters models). The three models that are proposed show a better performance than Freundlich, Langmuir. The calculation of the parameters of the different adsorption models was performed on MATLAB using genetic algorithms. Thermodynamic analysis of sorption isotherms suggest that sorption process of humic acid is spontaneous (ΔG°<0), with a positive enthalpy variation, characteristic of an endothermic process.

Numerical Study of lead-free halide perovskites solar cells using Efficient materials as electron transport materials

2025-02-25T04:23:49+00:00

This work presents a comprehensive theoretical analysis aimed at finding the elements that impede the efficiency of KGeCl3 solar cells. The aim of our investigation is to examine the impact of various characteristics to enhance its performance. The improved design exceeds the baseline, attaining a JSC of 37.08 mA/cm², Voc of 0.77 V, and FF of 60.80%, therefore indicating the possibility to reach an efficiency of up to 17.57% by the strategic optimization of 2D materials as the electron transport layer (ETL). The suggested analysis facilitates the identification of relevant degradation components and creates a basis for further design optimization. showcasing the effectiveness of our approach, the findings from this study not only highlight the critical factors affecting 2D perovskite solar cell performance but also provide a foundation for future research and optimization efforts.

Variational quantum Monte Carlo for the harmonium system

2025-04-17T12:53:51+00:00

Relatively good accuracy (< 2%) for intermediate and strong regime for the ground state energy of the harmonium system (Hook's atom) was obtained by variational Monte-Carlo (VMC) calculations. Our study focus on the variation of the ground state energy with respect to the oscillation frequency ω and the balance between the three different part of the energy (kinetic, coulomb and harmonic). Results were compared with several exactly known values of ground state energy for a series of discreet but limited values of the oscillation frequency.

Formulation d’encre industrielle à base d'eau comme solution écologique

2025-02-22T14:08:46+00:00

Les encres à base d'eau représentent une alternative écologique et performante pour une qualité d'impression optimale. Les encres aqueuses offrent des performances de 20 à 30% supérieures à celles des encres à base de solvants, avec l’avantage d'obtenir une viscosité stable, réduisant ainsi la nécessité d'ajouter des solvants pendant l'impression. Cette étude propose une formulation d’encre à base d'eau pour l'imprimerie industrielle, offrir une alternative plus respectueuse de l'environnement diminuer les émissions de composés organiques volatils (COV) et les dangers sur la santé liée à l'utilisation de solvants chimiques en utilisant de l'eau comme base. La composition chimique est variée entre l’eau distillée avec un pourcentage (60-70 %), et d’autres additifs comme (l’antimousse, accélérateur ou retardateur de séchage et les pigments selon la couleur désirée. La nouvelle formulation assure une amélioration de qualité et diminuer les impacts environnementaux.

Etude in-silco via docking moléculaire de l'inhibition de la xanthine oxydoréductase et du NADPH oxydase par la zéaxanthine et l'astaxanthine

2025-05-01T20:52:05+00:00

La recherche en chimie et biologie ne peut actuellement se passer des
outils informatiques pour traiter les données produites et optimiser ses
avancées. L’un de ces outils est la modélisation moléculaire et plus
précisément l’amarrage moléculaire (plus souvent connu sous le terme
"docking"). Le docking moléculaire est principalement utilisé pour prédire
et reproduire les complexes ‘’protéines-ligands’’ en reconnaissant les
différents types d'interactions.
Dans ce travail. Nous avons utilisé l'approche du docking moléculaire pour
étudier et vérifier l'activité antioxydante de deux molécules « astaxanthine
et zéaxanthine » en utilisant le logiciel de docking iGEMDOCK. Il consiste
à vérifier l’interaction entre les deux enzymes : NADPH oxydase et la
xanthine oxydase qui sont impliquées dans la production endogène des
radicaux libres avec deux antioxydants puissants : la zéaxanthine et
l’astaxanthine. Les résultats de notre approche in-silico ont prouvé que
l’astaxanthine et la zéaxanthine ont une bonne affinité avec les deux
enzymes.