Dr Vinura Udaraka Wickramasinghe Wickrama Appuhamilage
Academic and research departments
Advanced Technology Institute, Faculty of Engineering and Physical Sciences.About
My research project
Large scale manufacturing of Organic Photovoltaic CellsMy doctoral research has been focused on addressing the key challenges that limit the commercial deployment of organic photovoltaics (OPVs), including operational stability, manufacturing scalability, and dependence on costly electrode materials. OPVs are an emerging solar energy technology that offer unique advantages over conventional photovoltaics, including lightweight construction, mechanical flexibility, semi-transparency, and compatibility with low-cost solution processing, making them attractive for both outdoor renewable energy generation and indoor energy-harvesting applications.
A major focus has been the development of alternative cathode structures that reduce reliance on expensive silver electrodes. Through the design of an optimized Ag/Cu bilayer cathode, silver consumption was reduced by approximately 60% while maintaining device performance and significantly improving operational stability compared with devices employing copper-only electrodes. Another key aspect of the project investigates high-performance OPVs for indoor energy harvesting. By systematically comparing bulk heterojunction (BHJ) and layer-by-layer (LBL) architectures using advanced ternary active-layer systems, the work demonstrated improved charge extraction, reduced trap-assisted recombination, and enhanced voltage retention under low-light conditions. These optimizations enabled OPV devices to achieve a power conversion efficiency (PCE) of 29.99% under indoor illumination, highlighting their potential as sustainable power sources for Internet of Things (IoT) devices and self-powered electronics.
To address long-term stability and manufacturing reproducibility, the research further developed an optimized OPV device stack incorporating the polymeric electron transport layer PDINN in place of the conventional C60/BCP layers. This approach produced OPVs with efficiencies approaching 19% PCE under standard solar illumination while delivering a remarkable 97% improvement in device lifetime (T80) under ambient operating conditions. The optimized device architecture was subsequently translated to scalable fabrication through bar-coating techniques, enabling the production of larger-area OPV mini-modules with uniform and reproducible performance, demonstrating compatibility with industrial roll-to-roll manufacturing processes.
Overall, this research contributes to the development of commercially relevant organic solar technologies by establishing practical design strategies for reducing material costs, improving operational stability, optimizing performance for indoor and outdoor applications, and enabling scalable manufacturing. The outcomes provide important insights for the future realization of efficient, durable, and sustainable organic photovoltaic systems.
My doctoral research has been focused on addressing the key challenges that limit the commercial deployment of organic photovoltaics (OPVs), including operational stability, manufacturing scalability, and dependence on costly electrode materials. OPVs are an emerging solar energy technology that offer unique advantages over conventional photovoltaics, including lightweight construction, mechanical flexibility, semi-transparency, and compatibility with low-cost solution processing, making them attractive for both outdoor renewable energy generation and indoor energy-harvesting applications.
A major focus has been the development of alternative cathode structures that reduce reliance on expensive silver electrodes. Through the design of an optimized Ag/Cu bilayer cathode, silver consumption was reduced by approximately 60% while maintaining device performance and significantly improving operational stability compared with devices employing copper-only electrodes. Another key aspect of the project investigates high-performance OPVs for indoor energy harvesting. By systematically comparing bulk heterojunction (BHJ) and layer-by-layer (LBL) architectures using advanced ternary active-layer systems, the work demonstrated improved charge extraction, reduced trap-assisted recombination, and enhanced voltage retention under low-light conditions. These optimizations enabled OPV devices to achieve a power conversion efficiency (PCE) of 29.99% under indoor illumination, highlighting their potential as sustainable power sources for Internet of Things (IoT) devices and self-powered electronics.
To address long-term stability and manufacturing reproducibility, the research further developed an optimized OPV device stack incorporating the polymeric electron transport layer PDINN in place of the conventional C60/BCP layers. This approach produced OPVs with efficiencies approaching 19% PCE under standard solar illumination while delivering a remarkable 97% improvement in device lifetime (T80) under ambient operating conditions. The optimized device architecture was subsequently translated to scalable fabrication through bar-coating techniques, enabling the production of larger-area OPV mini-modules with uniform and reproducible performance, demonstrating compatibility with industrial roll-to-roll manufacturing processes.
Overall, this research contributes to the development of commercially relevant organic solar technologies by establishing practical design strategies for reducing material costs, improving operational stability, optimizing performance for indoor and outdoor applications, and enabling scalable manufacturing. The outcomes provide important insights for the future realization of efficient, durable, and sustainable organic photovoltaic systems.
Teaching
Conducting laboratory demonstrations for EEE2036 LABORATORIES, DESIGN & PROFESSIONAL STUDIES III, EEE2037 LABORATORIES, DESIGN & PROFESSIONAL STUDIES IV modules from 2022-2025.
Sustainable development goals
My research interests are related to the following:
Publications
The studies discussed in this research paper mainly focus on a novel method of using magnetic field densities to locate any kind of fault that occurs in medium voltage overhead lines. The first part of this project is the optimization of hall effect sensors for this approach. For that, several sensor positions were reviewed, so that the maximum resultant magnetic field flux is subjected to determine the magnetic field variations of the lines more accurately where a contactless measure monitoring system is proposed. In the second stage of the project, modelling of the hall effect sensor and communication platform was carried out. The impact of the existing noise parameter is also addressed to validate the algorithm for practical implementation. Finally, the expected results were obtained using a modelled distribution line network. This paper covers developing an algorithm to locate distribution line faults at any kind of faulty condition. The algorithm was developed by analyzing the simulation results and the graphs obtained through several line faulty conditions, using MATLAB Simulink. The fault detection method mainly depends on the significant variation of the magnetic field density locating the fault is done by comparing the peak values at each sensor node. To validate the modelled power system simulation, a successful comparison was carried out with the data received from a real-world existing distribution line network, modelled in LECO. The final results of the modelled system verified the validity of the proposed algorithm for fault locating of medium voltage overhead lines.
Second-generation solar cells, commonly known as thin-film solar cells, have emerged as promising alternatives to traditional silicon-based first-generation photovoltaic cells. The superstrate configuration is the most widely used structure for constructing thin-film solar cells. Nevertheless, light reflection from the front cover glass surface significantly contributes to energy losses in thin-film solar cells. In this study, a ZnO anti-reflection (AR) coating was introduced using the spin coating technique on a glass/FTO/CdS/CdTe/Cu/Au substrate to improve the power conversion efficiency of the solar cell by reducing front-surface reflectance. The ZnO layer deposited at 3000 rpm in 15 s showed the minimum reflectance and higher transmittance over a wavelength range of 500-900 nm. Further, the thickness of the film under optimal conditions was 63.32 nm, which is compatible with the ideal theoretical AR coating thickness of 65 nm. Comparing the device performance of the CdS/CdTe solar cell with and without AR coating, all tested devices showed an average short-circuit current density improvement of 6.8% and overall enhancement in power conversion efficiency of 9.3%.