Solar EnergyPub Date : 2025-07-10DOI: 10.1016/j.solener.2025.113759
Mahmoud M. Abd-Elhady , Osama M. Agwa , Mohamed K. Bayoumy , Rahaf B. Rizk , Ibrahim I. El-Sharkawy
{"title":"Experimental investigation of hybrid photovoltaic-thermal system: Integration of concentration, tracking, and cooling mechanisms","authors":"Mahmoud M. Abd-Elhady , Osama M. Agwa , Mohamed K. Bayoumy , Rahaf B. Rizk , Ibrahim I. El-Sharkawy","doi":"10.1016/j.solener.2025.113759","DOIUrl":"10.1016/j.solener.2025.113759","url":null,"abstract":"<div><div>This study presents an experimental investigation into the performance of a hybrid photovoltaic-thermal system through the integration of cooling, concentration, and tracking technologies. The research addresses several key challenges related to photovoltaic panels, including reduced efficiency due to high surface temperatures, large installation areas, and suboptimal solar energy capture. A comprehensive experimental setup was designed, featuring active water cooling through roll-bond heat exchangers, flat mirror concentrators, and a dual-axis solar tracker. The system was tested with three different configurations under actual outdoor climatic conditions at Damietta University in Egypt, and their performances were compared to those of a conventional photovoltaic panel. The results revealed that the combined configuration of cooling, tracking, and concentration mechanisms achieved the highest performance improvement, leading to a relative electrical efficiency enhancement up to 40 % compared to the conventional panel, with an average relative enhancement of 27 % throughout the day, and a peak power output of 340 W at noon. Furthermore, the system showed thermal energy recovery with an efficiency up to 75 %, illustrating its dual functionality in both electricity and thermal generation. These results highlight the potential of integrated photovoltaic-thermal systems to enhance electrical energy production, raise sustainability, and reduce dependence on non-renewable sources.</div></div>","PeriodicalId":428,"journal":{"name":"Solar Energy","volume":"299 ","pages":"Article 113759"},"PeriodicalIF":6.0,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144587924","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Solar EnergyPub Date : 2025-07-10DOI: 10.1016/j.solener.2025.113771
Wanxing Pu , Shengjie Wang , Jiapeng Liu , Yahui Wang , Ruijun Cui , Junhu Hu , Zhiguo Shi , Xiaoyan Zhao , Xiang Yu
{"title":"Research on horizontal topology optimization fins in latent heat storage unit","authors":"Wanxing Pu , Shengjie Wang , Jiapeng Liu , Yahui Wang , Ruijun Cui , Junhu Hu , Zhiguo Shi , Xiaoyan Zhao , Xiang Yu","doi":"10.1016/j.solener.2025.113771","DOIUrl":"10.1016/j.solener.2025.113771","url":null,"abstract":"<div><div>Adding fin structures enhances the heat transfer performance of latent thermal energy storage (LHTES) units. Current research on fin optimization focuses mainly on single or multiple fin parameters, but fin optimization requires considering the interdependencies of multiple parameters. Topology optimization can generate an optimized fin structure directly under specific conditions, simplifying the process and improving performance. This study investigates the effects of penalty index (1–9), filter radius (0.5–3 mm), projection slope (1–9), and projection point (0.1–0.9) on topology-optimized (TO) horizontal fins using variable density method-based continuous topology optimization theory. Results show that selecting appropriate design parameters is crucial for effective fin optimization. Comparing annular fins and TO horizontal fins reveals that TO horizontal fins significantly reduce melting time by up to 65.68 %. Increasing the volume fraction of TO horizontal fins improves melting efficiency to a certain limit, with diminishing returns as the fraction increases. A fin volume fraction of 12.5 % offers the best balance between efficiency and heat storage capacity. Two simplified schemes are proposed: removing thin fins and tips (Simplified Scheme 1) has minimal impact on heat transfer while reducing melting time by 2.5 %, whereas eliminating secondary bifurcation structures (Simplified Scheme 2) slightly decreases performance, increasing melting time by 7.6 %.</div></div>","PeriodicalId":428,"journal":{"name":"Solar Energy","volume":"300 ","pages":"Article 113771"},"PeriodicalIF":6.0,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144588306","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Solar EnergyPub Date : 2025-07-10DOI: 10.1016/j.solener.2025.113766
Shuo Ji, Yonghe Lao, Lishuang Cui, Hua Zhao, Lei Shi
{"title":"Snowflakes-Shaped Cu2S/Cd0.5Mn0.5S S-scheme heterojunction for enhanced photocatalytic hydrogen production and reduction of U(VI)","authors":"Shuo Ji, Yonghe Lao, Lishuang Cui, Hua Zhao, Lei Shi","doi":"10.1016/j.solener.2025.113766","DOIUrl":"10.1016/j.solener.2025.113766","url":null,"abstract":"<div><div>In this study, snowflake-like Cu<sub>2</sub>S was synthesized first. Subsequently, Cd<sub>0</sub>.<sub>5</sub>Mn<sub>0</sub>.<sub>5</sub>S (CMS) nanoparticles were evenly grown on the surface of the snowflake-like Cu<sub>2</sub>S, leading to the successful preparation of Cu<sub>2</sub>S/Cd<sub>0</sub>.<sub>5</sub>Mn<sub>0</sub>.<sub>5</sub>S (Cu<sub>2</sub>S/CMS) snowflake-like composites for the first time. When compared with pristine CMS, the optimal 1-Cu<sub>2</sub>S/CMS composite demonstrated an outstanding H<sub>2</sub> evolution rate of 3419.3 μmolg<sup>–1</sup>h<sup>–1</sup>, and it was 3.85 times the value of that of bare CMS. Moreover, in the application of U(VI) reduction, the 1-Cu<sub>2</sub>S/CMS composite achieved a remarkable degradation rate of 93.9 % for U(VI), significantly surpassing that of pure CMS (63.6 %). Notably, it also exhibited excellent long-term stability. The superior photocatalytic performance of the Cu<sub>2</sub>S/CMS composites is mainly due to the development of an S-scheme heterojunction between CMS and Cu<sub>2</sub>S, along with the unique snowflake-like morphology. These features enabled efficient charge transfer pathways and enhanced the solar energy capture efficiency of the composites. The developed catalyst successfully achieved the dual-functional application of photocatalytic H<sub>2</sub> production and U(VI) reduction. In this regard, this investigation presents crucial understandings and functions as a remarkable benchmark for the creation of high-efficiency composite photocatalysts.</div></div>","PeriodicalId":428,"journal":{"name":"Solar Energy","volume":"300 ","pages":"Article 113766"},"PeriodicalIF":6.0,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144588307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Solar EnergyPub Date : 2025-07-10DOI: 10.1016/j.solener.2025.113757
Maya Mathew
{"title":"Numerical design and optimization of copper tin sulphide (CTS) sensitizer based quantum dot solar cell","authors":"Maya Mathew","doi":"10.1016/j.solener.2025.113757","DOIUrl":"10.1016/j.solener.2025.113757","url":null,"abstract":"<div><div>This work presents, for the first time, the theoretical design of an efficient CTS quantum dot sensitized solar cell (QDSSC), ITO/TiO<sub>2</sub>/CTS/HTL/Au, with an efficiency of 17.86 %, with CuSbS<sub>2</sub> as the hole transporting layer (HTL). Using SCAPS-1D software, optimization of each layer is done and a thorough investigation on defect densities, on layers as well as interfaces, is performed. Lower sensitizer thickness (1––10 nm) and higher HTL thickness (1 µm) are favourable for good efficiency. Defect densities of 10<sup>10</sup> cm<sup>−2</sup> to 10<sup>18</sup> cm<sup>−2</sup> are permissible for the sensitizer layer as well as for the TiO<sub>2</sub>/CTS interface. Only the defects in the HTL and CTS/HTL interface were found to affect the cell efficiency and so these defects should be kept at a minimum of 10<sup>10</sup> cm<sup>−2</sup>. The sensitizer being quantum dots, the predominant recombination is non– radiative, Shockley Read Hall recombination; Auger recombination was found to be negligible. The cell efficiencies reported in the paper are above the efficiencies reported for the thin film solar cells of CTS. The novelty of this work is that a practical, environment friendly, cost effective and efficient quantum dot sensitized solar cell has been proposed, taking into account all of the resistive parameters which could affect the cell efficiency in real.</div></div>","PeriodicalId":428,"journal":{"name":"Solar Energy","volume":"300 ","pages":"Article 113757"},"PeriodicalIF":6.0,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144588305","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Solar EnergyPub Date : 2025-07-09DOI: 10.1016/j.solener.2025.113756
Roya Charghandeh, Abdollah Abbasi
{"title":"Impact of back-contact interface recombination on CZT(S,Se) thin-film solar cell efficiency: A theoretical perspective","authors":"Roya Charghandeh, Abdollah Abbasi","doi":"10.1016/j.solener.2025.113756","DOIUrl":"10.1016/j.solener.2025.113756","url":null,"abstract":"<div><div>Efficiency degradation resulting from interfacial carrier losses at the junction between the absorber layer and metallic back contact remains a major limitation for CZT(S,Se) thin-film photovoltaic devices—an environmentally friendly, earth-abundant kesterite material system. This study presents a theoretical framework that integrates both experimental trends and TCAD-based numerical simulations to examine and mitigate such interface-induced losses. The model incorporates critical interfacial phenomena, including band alignment and asymmetric recombination kinetics, without requiring high fabrication complexity. Simulation results demonstrate that targeted interface optimization—especially via barrier modulation and passivation techniques—can significantly reduce nonradiative recombination and improve carrier collection. The model predicts that optimizing the back interface can raise the power conversion efficiency from 12.6 % to > 17.0 %, mainly by enhancing the open-circuit voltage (V<sub>OC</sub>) and fill factor. This work introduces a novel, predictive framework that enables targeted interface engineering in kesterite solar cells and provides a valuable tool to guide next-generation experimental designs for high-efficiency, low-cost solar energy technologies.</div></div>","PeriodicalId":428,"journal":{"name":"Solar Energy","volume":"300 ","pages":"Article 113756"},"PeriodicalIF":6.0,"publicationDate":"2025-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144579806","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Solar EnergyPub Date : 2025-07-09DOI: 10.1016/j.solener.2025.113724
Hayder Altharwanee, Francisco Jurado, David Vera
{"title":"Experimental evaluation of photovoltaic performance utilizing a novel evaporative cooling method","authors":"Hayder Altharwanee, Francisco Jurado, David Vera","doi":"10.1016/j.solener.2025.113724","DOIUrl":"10.1016/j.solener.2025.113724","url":null,"abstract":"<div><div>A novel evaporative cooling design has been proposed and examined in hot climate conditions to enhance the electrical efficiency of the photovoltaic systems. The system has evaporative cooling positioned vertically behind the photovoltaic panel’s rear. The system is effective, economical, and easy to install. The study examined forced evaporative cooling on August 5, 6, 8, and 16, and natural evaporative cooling on July 27, 28, and 31. The findings demonstrated a notable reduction in photovoltaic panel temperature. The mean reduction in photovoltaic panel temperature through natural evaporative cooling was 3.98 °C, 3.74 °C, and 2.79 °C on the corresponding test days in July, respectively. Furthermore, by using forced evaporative cooling, the mean reduction in photovoltaic temperature was 7.07 °C, 8.44 °C, 7.65 °C, and 5.78 °C on the test days in August, respectively. The photovoltaic electrical efficiency improved by around 2.96%, 2.06%, and 2.05% on natural evaporative cooling days, respectively, and by about 3.77%, 4.33%, 4.62%, and 5.10% on forced evaporative cooling days, respectively. The cooling system lowers the PV panel surface temperature by promoting water evaporation, which reduces thermal stress and internal resistance in the solar cells, thereby enhancing electrical efficiency.</div></div>","PeriodicalId":428,"journal":{"name":"Solar Energy","volume":"299 ","pages":"Article 113724"},"PeriodicalIF":6.0,"publicationDate":"2025-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144580062","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Solar EnergyPub Date : 2025-07-08DOI: 10.1016/j.solener.2025.113768
M.C. Ndukwu , M.F. Umunna , T.E. Erokare , Elijah Ugwu , Adindu Linus–Chibuezeh , Leonard Akuwueke , Ogochukwu Umeh , Santiago Septien Stringel , Augustine Edet Ben , N.R. Nwakuba , F.I Abam , Hongwei Wu , M. Simo-Tagne
{"title":"Comparative analysis of charcoal-starch composite as a heat absorber in solar drying of water yam (Dioscorea alata)","authors":"M.C. Ndukwu , M.F. Umunna , T.E. Erokare , Elijah Ugwu , Adindu Linus–Chibuezeh , Leonard Akuwueke , Ogochukwu Umeh , Santiago Septien Stringel , Augustine Edet Ben , N.R. Nwakuba , F.I Abam , Hongwei Wu , M. Simo-Tagne","doi":"10.1016/j.solener.2025.113768","DOIUrl":"10.1016/j.solener.2025.113768","url":null,"abstract":"<div><div>The objective of this study is to assess the feasibility of replacing the aluminium-plate absorber, which carries high embodied energy, with an environmentally friendly charcoal-based alternative in solar dryer design. Therefore, two solar dryers with aluminium-plated absorber (SDAPA) and charcoal bed absorber (SDCBA) were developed, and their thermodynamic performance and drying kinetics were compared for drying water yam. SDAPA raised the inlet air temperature by 2.1–6.3 °C, while it was 1.4–6.3 °C for SDCBA. The average thermal efficiencies were 44.93 % for SDAPA and 44.77 % for SDCBA, with an average heat utilization ratio of 46 % and 43 %, respectively. Drying water yam from initial moisture content of 69.45 %wb to 7.41 ± 0.32 % took 16 h for SDAPA, 17 h for SDCBA, and 24 h for sun-drying with average effective moisture diffusivities of 4.51 × 10<sup>−10</sup>, 3.3 × 10<sup>−10</sup>, and 2.56 × 10<sup>−10</sup> m<sup>2</sup>/s, respectively. The specific energy utilisation varied from 0.239 to 14.07 W/kg for SDAPA and 0.37 to 15.07 W/kg for SDCBA. The SDCBA mitigated 6782.404 tons of CO<sub>2</sub> per year, translating to $98,344.87 in earned carbon credits, while it was 6465.87 tons and $93,755.12 for SDAPA. Modified Henderson and Pabis model best fitted the drying curve of water yam. This study demonstrates the potential of charcoal as a sustainable alternative to aluminium-plate as an absorber in solar dryers.</div></div>","PeriodicalId":428,"journal":{"name":"Solar Energy","volume":"300 ","pages":"Article 113768"},"PeriodicalIF":6.0,"publicationDate":"2025-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144572446","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Solar EnergyPub Date : 2025-07-08DOI: 10.1016/j.solener.2025.113767
S. Madhankumar , Veera Reddy Aduru , V.R. Lenin , V. Suresh Kannan , Akhilesh Kumar Singh , N.V.S. Swamy Chinamilli
{"title":"Analysis of thermal performance and drying kinetics of indirect solar drying under natural and forced convection","authors":"S. Madhankumar , Veera Reddy Aduru , V.R. Lenin , V. Suresh Kannan , Akhilesh Kumar Singh , N.V.S. Swamy Chinamilli","doi":"10.1016/j.solener.2025.113767","DOIUrl":"10.1016/j.solener.2025.113767","url":null,"abstract":"<div><div>Solar drying offers an effective and sustainable method for preserving agricultural products, particularly in regions with limited access to conventional energy. This study evaluates the performance of an Indirect-Type Solar Dryer (ITSD) for drying Bitter Gourd Slices (BGS), comparing natural and forced convection modes. The ITSD system comprises a V-grooved absorber solar collector, aluminium-finned paraffin wax as thermal storage, a drying chamber, and a blower operating at 0.064 kg/s for forced convection. Natural convection airflow ranged from 0.019 to 0.033 kg/s. Key performance indicators, including collector and dryer efficiencies, drying kinetics, Specific Energy Consumption (SEC), and Specific Moisture Extraction Rate (SMER), were experimentally analyzed. Mathematical modelling was applied to describe and predict the drying behaviour of BGS, offering insight into moisture removal dynamics. The average exit air temperature from the collector was 40.33 °C for natural convection and 38.76 °C for forced convection, with a higher temperature in natural convection due to lower airflow. Moisture content was reduced from 92 % to 12 % (wet basis) in 15 h under natural convection and in 12 h under forced convection. System efficiencies averaged 18.13 % and 19.35 % for natural and forced modes, respectively. SEC and SMER were 12.22 kW-h/kg and 0.084 kg/kW-h for natural, and 13.14 kW-h/kg and 0.079 kg/kW-h for forced convection. Despite higher air temperature in natural convection, forced convection demonstrated superior overall drying performance and is thus recommended for food processing applications where controlled and uniform drying is essential.</div></div>","PeriodicalId":428,"journal":{"name":"Solar Energy","volume":"299 ","pages":"Article 113767"},"PeriodicalIF":6.0,"publicationDate":"2025-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144572078","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Solar EnergyPub Date : 2025-07-07DOI: 10.1016/j.solener.2025.113762
Qiangqiang Xiao , Mengqian Wang , Hongda Tang , Hongli Guo , Ndzondelelo Bingwa , Shijie Li , Guoning Li , Hui Li
{"title":"A potential building heating strategy integrating solar radiation absorption and thermal energy storage","authors":"Qiangqiang Xiao , Mengqian Wang , Hongda Tang , Hongli Guo , Ndzondelelo Bingwa , Shijie Li , Guoning Li , Hui Li","doi":"10.1016/j.solener.2025.113762","DOIUrl":"10.1016/j.solener.2025.113762","url":null,"abstract":"<div><div>Building heating accounts for a substantial portion of energy consumption, leading to significant carbon emission. This study presents a promising heating strategy that integrates solar radiation absorption with thermal energy storage using phase change materials (PCMs), significantly enhancing indoor thermal comfort while reducing energy consumption. A composite PCM comprised of CaCl<sub>2</sub>·6H<sub>2</sub>O and expanded graphite was developed to achieve these goals, offering excellent thermal storage properties and a solar absorptance up to 91.4 %, allowing it to efficiently capture solar radiation. The composite PCM was formed into plate structures and incorporated into building walls with the aim of evaluating its thermal performance. Experimental findings show that the composite PCM plate, with a thickness 10 mm and installed on the southern wall of the test chamber, achieved a duration of thermal comfort (DTC) of 4.06 h—414 % longer than the reference chamber, which only achieved 0.79 h. Numerical simulations further optimized the design, revealing that a 25 mm thick PCM plate, paired with a 60° south-by-east building orientation, provided optimal performance. It achieved a DTC of 13.5 h, which is 233 % longer than the 10 mm thick PCM plate. Moreover, this optimized design ensures that the indoor temperature reaches a comfortable level by 10:00 AM. This study highlights the potential of PCM-based solar heating systems to reduce energy consumption and provides a sustainable solution for building heating in cold climates.</div></div>","PeriodicalId":428,"journal":{"name":"Solar Energy","volume":"299 ","pages":"Article 113762"},"PeriodicalIF":6.0,"publicationDate":"2025-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144572079","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Solar EnergyPub Date : 2025-07-07DOI: 10.1016/j.solener.2025.113751
Naoufal Ennouhi , Yassine Chouimi , Noureddine Ben Afkir , Abdeljalile Er-rfyg , Sanaa Ammari , Massaab El Ydrissi , Zouheir Sekkat
{"title":"Silver and sodium incorporation into wide bandgap CZTS absorbers on transparent back electrodes and their application in kesterite/c-silicon tandem solar cells: Experiments and simulations","authors":"Naoufal Ennouhi , Yassine Chouimi , Noureddine Ben Afkir , Abdeljalile Er-rfyg , Sanaa Ammari , Massaab El Ydrissi , Zouheir Sekkat","doi":"10.1016/j.solener.2025.113751","DOIUrl":"10.1016/j.solener.2025.113751","url":null,"abstract":"<div><div>In recent years, kesterite solar cells have emerged as a promising candidate for integration as top subcells in tandem structures with silicon solar cells. Nevertheless, the production of high-quality kesterite absorbers on transparent substrates has remained a significant challenge. In this study, the combination of silver (Ag) alloying and sodium (Na) doping was employed to enhance the properties of copper zinc tin sulfide (CZTS) absorbers developed on FTO (fluorine-doped tin oxide) back electrodes using the sol–gel method. X-ray diffraction demonstrated a notable enhancement in the crystallinity and phase composition of the kesterite materials with the introduction of silver. Furthermore, Raman spectroscopy indicated a more organized matrix with a considerable reduction in Cu/Zn disorder and CuZn defect density in the kesterite materials following the incorporation of silver. Optical analysis exhibited a slight increase in the kesterite optical bandgap from 1.53 to 1.57 eV due to the presence of silver atoms. A finite-difference time-domain (FDTD) optical simulation was conducted using realistic optical inputs to calculate the transmitted light from the FTO/CZTS/CdS/ZnO/ITO solar structure. Subsequently, the performance of a well-established c-Si bottom subcell (with state-of-the-art efficiency) under calculated transmission was evaluated using the Solar Cell Capacitance Simulator (SCAPS-1D) for electrical simulation. The simulated tandem device achieved an efficiency of 14.5 %, which is lower than that of a crystalline silicon (c-Si) solar cell under AM1.5 due to lower transmittance. This resulted in only 6 % efficiency from c-Si in the tandem configuration, in addition to the lower electrical performance of the kesterite top subcell with only 7.8 % efficiency. These findings suggest that incorporating silver represents a promising approach to enhancing the properties of kesterite materials on transparent back electrodes. However, further optical improvements are necessary to fully realize the potential of kesterite materials for tandem applications.</div></div>","PeriodicalId":428,"journal":{"name":"Solar Energy","volume":"299 ","pages":"Article 113751"},"PeriodicalIF":6.0,"publicationDate":"2025-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144569835","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}