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.
Researchers often equate database accounting models in general and the Resources-Events-Agents (REA) accounting model in particular with events accounting as proposed by Sorter (1969). In fact, REA accounting, database accounting, and events accounting are very different. Because REA accounting has become a popular topic in AIS research, it is important to agree on exactly what is meant by certain ideas, both in concept and in historical origin. This article clarifies the analyzing framework of REA accounting model and highlights the differences between the terms events accounting, database accounting, semantically-modeled accounting, and REA accounting. It als
... Show MoreIn this research, annealed nanostructured ZnO catalyst water putrefaction system was built using sun light and different wavelength lasers as stimulating light sources to enhance photocatalytic degradation activity of methylene blue (MB) dye as a model based on interfacial charges transfer. The structural, crystallite size, morphological, particle size, optical properties and degradation ability of annealed nanostructured ZnO were characterized by X-Ray Diffraction (XRD), Atomic Force Microscopy (AFM) and UV-VIS Spectrometer, respectively. XRD results demonstrated a pure crystalline hexagonal wurtzite with crystalline size equal to 23 nm. From AFM results, the average particle size was 79.25nm. All MB samples and MB with annealed nanostr
... Show MoreThe efficient behavior of a low-concentrating photovoltaic-thermal system with a micro-jet channel (LCPV/T-JET) and booster mirror reflector is experimentally evaluated here. Micro-jets promote the thermal management of PV solar cells by implementing jet water as active cooling, which is still in the early stages of development. The booster mirror reflector concentrates solar irradiance into solar cells and improves the thermal, electrical, and combined efficiencies of the LCPV/T-JET system. The LCPV/T-JET system was tested under ambient weather conditions in the city of Bangi, Selangor, Malaysia, and all data was recorded between 10:00 a.m. and 4:00 p.m. Parametric studies were conducted to compare the performance of the LCPV/T-JET system
... Show MoreNeed organizations today to move towards strategic thinking which means analyzing situations faced by particular challenges of change in the external environment, which makes it imperative for The Organization That to reconsider their strategies and orientations and operations, a so-called re-engineering to meet those challenges and pressures, to try to achieve improvement root in the installation of the organization and methodscompletion of its work towards achieving high levels of performance and that is reflected to achieve its objectives, and this is what aims to Current search to deal with implications characteristics of strategic thinking in the stages of application re-engineering business of the company General Industries
... Show MoreCharge transfer in styryl dyes STQ-1, STQ-2,and STQ-3 with organic media system has been studied theoretically depending on the Franck- Condon rule and continuum dielectric model . The reorientation energies (eV) were evaluated theoretically depending on dipole momentum, dielectric constant , and refrective index n. The rate constant of charge transfer has been calculated depending on the reorientation energy (eV) ,effective free energy , potential height barrier , and coupling coefficient . A matlap program has been written to calculated the rate constant of charge transfer and other parameter. The results of calculations show that STQ-2 dye is more reaction for charge transfer compare with STQ-1 and STQ-3 dyes
Iraq has confronted a huge political transformations after 2003 which resembled and presented rapid changes from totalitarian regime into democracy's system , this phenomenon has become a feature embodied in a new political system, specifically is being a price for previous deprivation and despotism .So that, the nature of political work has been changed as a result of practicing new democratic values ,but the real challenges appeared by depending on the conformity and political compromise in dealing with all of crises and problems in the political life .
The future of political work in this nascent democracy could be prepared according to fulfillment an active doings values stretched on national unity and forgiveness from one side ,t
The performance evaluation process requires a set of criteria and for the purpose of measuring the level of performance achieved by the Unit and the actual level of development of its activities, and in view of the changes and of rapid and continuous variables surrounding the Performance is a reflection of the unit's ability to achieve its objectives, as these units are designed to achieve the objectives of exploiting a range of economic resources available to it, and the performance evaluation process is a form of censorship, focusing on the analysis of the results obtained from the achievement All its activities with a view to determining the extent to which the Unit has achieved its objectives using the resources available to it and h
... Show MoreGelatin is a valuable substance that is known to have a complex 3D structure, but it has limited adsorption efficiency, which limit its application at physiological temperature. In this paper, gelatin was improved by the addition of glutaraldehyde (GTA) to enhance its ability to adsorb dye in aqueous solution. The adsorption experiments were conducted under different conditions, such as the amount of adsorbent, the concentration of the dye, and the temperature. The study found that the qe by GTA-GE (4.978 to 23.056 mg/g) and GE (4.8 to 21.333 mg/g) increased with the increase of initial dye concentrations but decreased with the amount of adsorbent. The parameters at equilibrium were at a pH of 4 and a dose of adsorbent of 100 mg in
... Show MoreThe objective of this study is to verify the overall performance and evaluate the wastewater quality of the wastewater treatment plant at the Abu Ghraib Dairy Factory and compare the results with the Iraqi Quality Standards (IQS) for effluent disposal and with the national determinants of treated water use. Agricultural irrigation wastewater, which included daily assessment records of the main parameters affecting wastewater [five-day biochemical oxygen demand (BOD5), chemical oxygen demand (COD), total dissolved solids (T.D.S), total suspended solids (TSS), phosphate (PO4), nitrate (NO3), hydrogen ion concentration (pH)] obtained from the quality control department of Abu Ghraib dairy plant registered from January 2017 to December 2020. Th
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