Preferred Language
Articles
/
l-ZNT50BmraWrQ4dxFXc
Theoretical defect engineering in AgBiI4 for enhanced photovoltaic performance
...Show More Authors

Silver-bismuth iodide (ABI) ternary semiconductors, such as AgBi2I7, AgBiI4, Ag2BiI5, and Ag3BiI6, have emerged as promising lead-free light absorbers for photovoltaic applications due to their favorable optoelectronic properties. Despite recent advances that have improved power conversion efficiencies from ∼1% to over 5%, ABI-based solar cells still show substantial open-circuit voltage (VOC) losses of up to ∼1 V, which significantly hinder the device performance. These losses have been experimentally attributed to the non-radiative recombination originating from intrinsic defects, however, theoretical understanding of these defect mechanisms remains limited. Here, using density functional theory calculations, we systematically investigate the defect properties of AgBiI4. We identify the dominant intrinsic defects as acceptor-like Ag vacancies (VAg) and AgBi antisites, as well as donor-like Ag interstitials (Agi) and BiAg antisites. Among these defects, VAg and AgBi are shallow defects, while Agi and BiAg create deep trap states. Our calculations reveal that I-rich synthesis conditions with a carefully balanced Ag/Bi ratio are essential to suppressing the formation of deep defects and mitigating non-radiative recombinations. These insights provide theoretical guidance for defect modulation in ABI compounds and highlight AgBiI4 as a model system for understanding defect physics in ABI photovoltaic materials.

Scopus Crossref
View Publication
Publication Date
Wed Mar 18 2020
Journal Name
Baghdad Science Journal
A Software Defined Network of Video Surveillance System Based on Enhanced Routing Algorithms
...Show More Authors

Software Defined Network (SDN) is a new technology that separate the ‎control plane from the data plane. SDN provides a choice in automation and ‎programmability faster than traditional network. It supports the ‎Quality of Service (QoS) for video surveillance application. One of most ‎significant issues in video surveillance is how to find the best path for routing the packets ‎between the source (IP cameras) and destination (monitoring center). The ‎video surveillance system requires fast transmission and reliable delivery ‎and high QoS. To improve the QoS and to achieve the optimal path, the ‎SDN architecture is used in this paper. In addition, different routing algorithms are ‎used with different steps. First, we eva

... Show More
View Publication Preview PDF
Scopus (6)
Crossref (3)
Scopus Clarivate Crossref
Publication Date
Mon Jan 01 2024
Journal Name
Baghdad Science Journal
Enhanced Photocatalytic Activity of Cu2O/ZnO/GO Nanocomposites on the Methylene Blue Degradation
...Show More Authors

This study synthesized nanocomposite photocatalyst materials from a mixture of Cu2O nanoparticles, ZnO nanoparticles, and graphene oxide (GO) through coprecipitation and hydrothermal methods. This study aims to determine the optimum composition of Cu2O/ZnO/GO nanocomposites in degrading methylene blue. The nanocomposite was synthesized in two steps:  1  the synthesis of Cu2O and ZnO nanoparticles through the coprecipitation method and the preparation of GO through the modified Hummer method.  2  The preparation of Cu2O and ZnO nanoparticles mixtures with GO through the hydrothermal method to form Cu2O/ZnO/GO nanocomposites. The adsorption-photocatalysis process of methylene blue

... Show More
View Publication Preview PDF
Scopus (8)
Crossref (4)
Scopus Crossref
Publication Date
Mon Aug 12 2024
Journal Name
Applied Physics A
Fabrication and characterization of visible-enhanced CeO2/Si photodetectors using pulsed laser deposition
...Show More Authors

Nanostructured photodetectors have garnered great attention due to their enriched electronic and optical properties. In this work, we aim to fabricate a high-performance CeO2/Si photodetector by growing a CeO2 nanostructure film on a silicon substrate using the pulsed laser deposition (PLD) technique at different laser energy densities. The impact of laser energy density and the number of pulses on the morphological, optical, and electrical properties was studied. Field emission scanning electron microscopy (FESEM) results show that the CeO2 film has a spherical grain morphology with an average grain size ranging from 33 to 54 nm, depending on the laser energy density. The film deposited at various numbers of laser pulses also has spherical

... Show More
View Publication
Scopus (4)
Crossref (4)
Scopus Clarivate Crossref
Publication Date
Sun Nov 01 2015
Journal Name
Journal Of Engineering
Treatment of Wastewater Contaminated with Pesticide (Alachlor) by Solar Enhanced Advanced Oxidation Processes
...Show More Authors

The degradation performance of aqueous solution of pesticide Alachlor has been studied at solar pilot scale plant in two photocatalytic systems: homogeneous photocatalysis by photo-Fenton and heterogeneous photocatalysis with titanium dioxide. The pilot scale system included of compound parabolic collectors specially designed for solar photocatalytic applications, and installed at University of Baghdad, Department of Environmental Engineering back yard. The influence of different concentrations, H2O2 (200-2400 mg/l), Fe+2(5- 30 mg/l) and TiO2 (100-500 mg/l) and their relationship with the degradation efficiency were studied.

      The COD removal efficienc

... Show More
View Publication Preview PDF
Publication Date
Tue Feb 01 2022
Journal Name
Baghdad Science Journal
An Enhanced Approach of Image Steganographic Using Discrete Shearlet Transform and Secret Sharing
...Show More Authors

Recently, the internet has made the users able to transmit the digital media in the easiest manner. In spite of this facility of the internet, this may lead to several threats that are concerned with confidentiality of transferred media contents such as media authentication and integrity verification. For these reasons, data hiding methods and cryptography are used to protect the contents of digital media. In this paper, an enhanced method of image steganography combined with visual cryptography has been proposed. A secret logo (binary image) of size (128x128) is encrypted by applying (2 out 2 share) visual cryptography on it to generate two secret share. During the embedding process, a cover red, green, and blue (RGB) image of size (512

... Show More
View Publication Preview PDF
Scopus (15)
Crossref (9)
Scopus Clarivate Crossref
Publication Date
Mon Jul 01 2024
Journal Name
Journal Of Engineering
Design and Implementation of a Microstrip Six-Port Reflectometer (SPR) with Enhanced Bandwidth
...Show More Authors

A compact microstrip six-port reflectometer (SPR) with extended bandwidth is proposed in this paper. The design is based on using 16-dB multi-section coupled line directional couplers and a multi-section 3-dB Wilkinson power divider operating from 1 to 6 GHz. The proposed SPR employs only two calibration standards: a matched load and an open load. As compared to other dielectric substrates, fabricating the proposed SPR involves using a low-cost (FR4) substrate. A novel algorithm is also proposed to estimate the complex reflection coefficient over the frequency ranges at which the standard performance of the circuit components is not fully satisfied. The new algorithm is based on the circles’ intersection points, which have been de

... Show More
View Publication
Crossref (1)
Crossref
Publication Date
Mon Dec 18 2017
Journal Name
Al-khwarizmi Engineering Journal
Path Planning of an Autonomous Mobile Robot using Enhanced Bacterial Foraging Optimization Algorithm
...Show More Authors

This paper describes the problem of online autonomous mobile robot path planning, which is consisted of finding optimal paths or trajectories for an autonomous mobile robot from a starting point to a destination across a flat map of a terrain, represented by a 2-D workspace. An enhanced algorithm for solving the problem of path planning using Bacterial Foraging Optimization algorithm is presented. This nature-inspired metaheuristic algorithm, which imitates the foraging behavior of E-coli bacteria, was used to find the optimal path from a starting point to a target point. The proposed algorithm was demonstrated by simulations in both static and dynamic different environments. A comparative study was evaluated between the developed algori

... Show More
View Publication Preview PDF
Crossref (15)
Crossref
Publication Date
Sun Aug 03 2025
Journal Name
Journal Of Molecular Structure
Synergistic design of carbazole-bearing (D–π)₂-D–π–A architectures for dye-sensitized solar cells: Experimental and theoretical evaluations
...Show More Authors

Publication Date
Wed Oct 04 2023
Journal Name
History Of Medicine
Theoretical Biological Activities and Docking studies of new amino-acids Derivatives of Oseltamivir for The Treatment of Coronavirus Disease 2019
...Show More Authors

Antiviral medications may be the best choices for COVID-19 treatment until particular therapeutic treatments become available. Tamiflu (oseltamivir) is a neuraminidase inhibitor licensed for the management and defense against influenza types A and B. Oseltamivir-based medication combinations are currently being used to treat COVID-19 patients who also have the new coronavirus 1 SARS-CoV-2. 1 Oseltamivir administration was related with a less time spent in the hospital, quicker recovery 1 and discharge, and a decreased mortality rate. Docking is a modern computational method for identifying a hit molecule by assessing the binding ability of molecular medicines within the binding target pocket. In this work, we chose 21 ligand compounds that

... Show More
Publication Date
Tue Aug 02 2022
Journal Name
Karbala International Journal Of Modern Science
Performance Simulation for Adaptive Optics Technique Using OOMAO Toolbox
...Show More Authors

The Adaptive Optics technique has been developed to obtain the correction of atmospheric seeing. The purpose of this study is to use the MATLAB program to investigate the performance of an AO system with the most recent AO simulation tools, Objected-Oriented Matlab Adaptive Optics (OOMAO). This was achieved by studying the variables that impact image quality correction, such as observation wavelength bands, atmospheric parameters, telescope parameters, deformable mirror parameters, wavefront sensor parameters, and noise parameters. The results presented a detailed analysis of the factors that influence the image correction process as well as the impact of the AO components on that process

View Publication
Scopus (6)
Crossref (1)
Scopus Crossref