Solar photovoltaic (PV) is a well-known energy harvesting technology or a semiconductor device that is used in generating electricity from the sunlight via the conversion process. Currently, solar photovoltaic is increasingly growing as an alternative renewable energy in conventional power generation. There are two types of solar photovoltaic cells which are monofacial and bifacial solar cells. The difference between these two solar cells is, monofacial, only generate electricity when the light touches the front side whereas the bifacial solar cell does generate electricity from both the front and rear side. In this research project, the bifacial solar cell is used to fulfil the purpose of increasing the power conversion efficiency as it can generate power from both surfaces. The bifacial is known to produce more energy up to 27 % than the monofacial according to the claims of some manufacturers. The base of this bifacial solar cell is silicon. Silicon purely contains an atomic structure that makes it suitable and more stable to be the raw material of a semiconductor due to its behaviour to block and conduct electricity. This is mainly due to silicon having the conductive properties of metal as well as an insulator. The silicon wafer will undergo the whole fabrication process to become the semiconductor devices. However, there is a problem encountered with the PV cell when it is consistently improving and when analysing the potential areas: on the power conversion efficiency. This is one of the challenges that can be solved with a strategy to increase the availability of the photon trapping of the solar cell which we called as the surface passivation of the bifacial solar cell. Surface passivation is a way that can minimise the recombination loss and efficiency loss while enhancing the optical path length of the solar cell on the photon absorption. It is the most significant step to increase the efficiency of the bifacial solar cell which is also known as an anti-reflection coating (ARC) using dye-based coating techniques. The development of the anti-reflection (ARC) lays on the fabrication techniques, optical performance and the light trapping structures as well as their impact on its efficiency.
Surface passivation is the most significant step to keep the recombination loss at a tolerable minimum and avoid an unacceptably large efficiency loss when moving towards thinner silicon material. The surface passivation was investigated by using nanostructure molecules of DiO. This indicates that the light trapping inside the interface layers of silicon has a slow process of charge recombination before it reaches an equilibrium state. This is due to the interaction bonding between interfaces within boundary layers and dye molecules nanostructure. The short circuit current density increases as the dye molecule is applied on the solar cell. Bifacial solar cells are designed to trap light in both the front side and rear side. The main issues in the back surface were identified such as low efficiency, low photo generated current and low recombination losses. However, poor passivation and wafer thickness also can be one of the reasons that contribute to the recombination losses. Thus, to reduce the back-surface recombination in crystalline silicon solar cells is by using doped junction technique. These junctions are commonly known as back-surface fields (BSF). In general, the passivation techniques commonly use inorganic materials which may not give advantage on the research such as Silicon Nitride and Silicon Dioxide even though these materials can produce higher efficiency. Surface passivation is important in producing good dielectric properties but the use of silicon dioxide is unsuitable as it requires higher temperature and has a low reflective index. Meanwhile, as for the silicon nitride, even though it provides higher stability in trapping the light, it does release hazardous gas that might be harmful to people.
Bifacial solar cells offer numerous benefits, such as their applicability and compatibility with thin wafers, ability to endure high temperatures, utilisation of minimal metal materials, enhanced power generation, and a straightforward manufacturing process. Furthermore, this particular cell exhibits the ability to enhance the power density of the photovoltaic module in comparison to single-sided cells arranged in a side-by-side configuration, while simultaneously decreasing the expenses associated with the area of the photovoltaic system. One of the benefits includes a reduction in temperature within the working cell, as well as an increase in the maximum power output. This is attributed to the absence of aluminium metal, which results in a decrease in infrared absorption. A notable benefit of this particular cell is its ability to function optimally in a vertical arrangement, in contrast to the commonly employed single-sided solar cells that are typically mounted at a predetermined angle.
In this study, the three objectives mentioned in chapter 1 has been done which are first, to fabricate the bifacial silicon solar cell both front and rear side and observe its optical properties. Second, to measure the electrical properties of the bifacial silicon solar cell to obtain its Light-Current-Voltage and power conversion efficiency and lastly, to improve the efficiency of bifacial solar cells by surface passivation using dye molecules nanostructure. For the first objectives, the optical properties of the bifacial silicon solar cells have been achieved by fabricating the solar cell especially in texturing process. The topographical image of the textured surface helped in increasing the rate of light trapping into the material. The higher the surface roughness of the material, more light will be trapped inside to generate more electrical energy. Thus, the efficiency of the solar cells will be higher than non-textured surface.
In second objectives, the electrical properties of the bifacial silicon solar cells were measured by using the I-V measurement. The efficiency calculated from the data obtain of the front side is 3.6% while the rear side has 0.8%. The result showed that the back surface field has lower power conversion energy. This is might be due to the poor passivation or the thickness of the wafer. But, the cost is too high. Thus, there are some ways to overcome this problem with lower cost need which is using the dye-based material. Therefore, the experiment proven, that the dye help to increase the efficiency of the back surface of silicon by 2.5%.
 Jia, G., Steglich, M., Sill, I., and Falk, F. 2012. Core-shell Heterojunction Solar Cells on Silicon Nanowires Arrays. Solar Energy Materials and Solar Cells. 96: 226-230.
 S. Sepeai, M. Y. Sulaiman, K. Sopian, and S.H. Zaidi. 2012. Surface Passivation Studies on n+pp+ Bifacial Solar Cell. International Journal of Photoenergy.
 Mohd Sinin et al. 2015. Modification of BSF Layer in Bifacial Solar Cell via Photosensitization of Molecules Nanostructure. Jurnal Teknologi (Sciences & Engineering) 78:6–7.
 PVCDROM : https://www.pveducation.org
 N.G Semaltianos. 2007. Spin-coated PMMA films. School of Computing, Communications and Electronics, University of Plymouth, Drake Circus, Plymouth PL4 8AA, UK. Microelectronics Journal (2007) 754-761.
 William P. Eaton, Subhash H. Risbud, and Rosemary L. Smith. 1994. Silicon wafer-to-wafer bonding at T<2000C with polymethylmethacrylate. AIP (Applied Physics Letter) 65, 439 (1994)
 Christopher B. Walsh, Elias I. Franses. 2002. Ultrathin PMMA films spin-coated from toluene solutions. Science Direct. Elsevier. Thin Solid Film 429 (2003) 71-76.
 Peng Xiao et. al. 2022. Enhancing the efficiency and stability of Organic Silicon solar cells using graphene electrode and Double-layer Anti-reflection coating. Solar Energy 234 (2022) 111-118. State Grid Jiangsu Electric Power Co. Ltd. Research Institute, Nanjing 211 103, Jiangsu, PR China. https://doi.org/10.1016/j.solener.2022.01.063
 Sami Jouttijärvi, Gabriele Lobaccaro, Aleksi Kamppinen, Kati Miettunen, Benefits of bifacial solar cells combined with low voltage power grids at high latitudes, Renewable and Sustainable Energy Reviews, Volume 161, 2022, 112354, ISSN 1364-0321, ://doi.org/10.1016/j.rser.2022.112354.
 Shanmugam, Natarajan; Pugazhendhi, Rishi; Madurai Elavarasan, Rajvikram; Kasiviswanathan, Pitchandi; Das, Narottam (2020). Anti-Reflective Coating Materials: A Holistic Review from PV Perspective. Energies, 13(10), 2631–. doi:10.3390/en13102631
 Leon, J.J.D.; Hiszpanski, A.M.; Bond, T.C.; Kuntz, J.D. Design Rules for Tailoring Antireflection Properties of Hierarchical Optical Structures. Adv. Opt. Mater. 2017, 5, 1700080.
 Dong, C.; Lu, H.; Yu, K.; Shen, K.-S.; Zhang, J.; Xia, S.-Q.; Xiong, Z.-G.; Liu, X.-Y.; Zhang, B.; Wang, Z.-J.; et al. Low emissivity double sides antireflection coatings for silicon wafer at infrared region. J. Alloy Compd. 2018, 742, 729–735.
 Samajdar, D.P. Light-trapping strategy for PEDOT:PSS/c-Si nanopyramid based hybrid solar cells embedded with metallic nanoparticles. Sol. Energy 2019, 190, 278–285.
 Enrichi, F.; Quandt, A.; Righini, G.C. Plasmonic enhanced solar cells: Summary of possible strategies and recent results. Renew. Sustain. Energy Rev. 2018, 82, 2433–2439.
 Keith R. McIntosh; Gay Lau; James N. Cotsell; Katherine Hanton; Derk L. Batzner; Fabian Bettiol; Bryce S. Richards (2009). Increase in external quantum efficiency of encapsulated silicon solar cells from a luminiscent down-shifting layer., 17(3), 191-197. doi:10.1002/pip.867
 Suraya Shaban et al (2022). Bifacial dye-sensitized solar cells utilizing green-colored NIR sensitive unsymmetrical squaraine dye. Japanese Journal Applied Physics. 61 SB1005
 Kennedy, S.R.; Brett, M.J. Porous broadband antireflection coating by glancing angle deposition. Applied Optics. (2003). 42,4573
 G.K. Kiema, M.J. Colgan, M.J. Brett. (2005). Dye sensitized solar cells incorporating obliquely deposited titanium oxide layers. Solar Energy Mater. Solar Cells. 85, 321-331
 Wang Z., Yao N., Hu X., (2014). Single material TiO2 double layers antireflection coating with photocatalytic property prepared by magnetron sputtering technique. Vacuum, 108, 20-26
 Askar A. Maxim, Shynggys N. Sadyk, Damir Aidarkhanov, Charles Surya, Annie Ng, Yoon Hwae Hwang, Timur Sh. Atabev, and Askhat N. Jumabekov. (2020). PMMA Thin Film Embedded Carbon Quantum Dots for Post-Fabrication Improvement of Light Harvesting in Perovskite Solar Cells. Nanomaterials. 10, 291
 Anurag Roy, Aritra Ghosh, Shubhranshu Bhandari, Tapas Kumar Mallick, and Senthilarasu Sundaram. (2020). Realization of Poly (methyl methacrylate) Encapsulated Solution-Processed Carbon-Based Solar Cells: Emerging Candidate for Buildings’ Comfort. Ind. Eng. Chem. Res. 19 May 2020.
 Alex C. Mayer, Shawn R. Scully, Brian E. Hardin, Michael W. Rowell, and Michael D. McGehee. (2007). Polymer-based solar cells. Stanford University, Stanford, CA 94305, USA
 Ibtissam Lamaamar, Amine Tilioua, Moulay Ahmed Hamdi Alaoui. (2022). Thermal performance analysis of a poly c-Si PV under semi-arid conditions. Material Science for Energy Technologies, 5, 243-251
 Tilioua A. Investigation of the thermo-physical properties of poly (methyl methacrylate)-based Plexiglass to improve performance of solar cells, Material Science for Energy Technologies, 4(34), (2021), 349-356
 Faiz Rahman, D.J. Carbaugh, J.T. Wright, et al. A review of polymethyl methacrylate (PMMA) as a versatile lithographic resist – With emphasis on UV exposure, Microelectronic Engineering (2020), S0167-9317(20)30026-5
 J.Y. Chen, W.L. Chang, C.K. Huang, and K.W. Sun. (2011). Biomimetic nanostructured antireflection coating and its application on crystalline silicon solar cells. Department of Applied Chemistry. Vol. 19, No. 15