Ukrainian Journal of Physical Optics


2022, Volume 23, Issue 3


ISSN 1816-2002 (Online), ISSN 1609-1833 (Print)

Pre-themalizational effect of hot carriers on photovoltage formation in a solar cell

Masalskyi O., Gradauskas J.

Vilnius Gediminas Technical University, Saulėtekio Avenue 11, 10223 Vilnius, Lithuania vilniustech@vilniustech.lt;

ABSTRACT

Although the power-conversion efficiency of single-junction solar cells achieved in practice is slowly increasing in the recent years, it still remains well below the theoretical Shockley–Queisser limit. We analyze in this relation the impact of hot carriers which represents an additional fundamental mechanism of intrinsic losses. We suggest that it is one of the reasons why the theoretical efficiency limit cannot be reached. We demonstrate that all of the solar photons participate in carrier heating, except for those having the energy equal to the bandgap. This supplies the process with more than 52% of the total incident solar energy. Finally, we give experimental evidence to a hot-carrier photovoltage (PV) arising in Si and GaAs cells before thermalization process. This PV is opposite to a classical PV induced by carrier generation, thus hindering the efficiency of p-n-junction solar cells.


Keywords:
solar cells, p-n junctions, photovoltage, hot carriers, efficiency

UDC: 535.215

    1. The National Renewable Energy Laboratory (n. d.). Best Research-Cell Efficiency Chart. Nrel. Gov. Retrieved March 11, 2022. URL: https://www.nrel.gov/pv/cell-efficiency.html
    2. Green M A, 2015. Forty years of photovoltaic research at UNSW. Journal and Proceedings of the Royal Society of New South Wales. 148: 2-14.
    3. Shockley W and Queisser H J, 1961. Detailed balance limit of efficiency of p-n junction solar cells. J. Appl. Phys. 32: 510-519. doi:10.1063/1.1736034
    4. Hirst L C and Ekins-Daukes N J, 2011. Fundamental losses in solar cells. Prog. Photovolt. Res. Appl. 19: 286-293. doi:10.1002/pip.1024
    5. Nozik A J, 2018. Utilizing hot electrons. Nature Energy. 3: 170-171. doi:10.1038/s41560-018-0112-5
    6. Shrestha S, Chung S, Liao Yu, Cao W, Gupta N, Zhang Y, Wen X, Conibeer G, 2017. Development of absorber and energy selective contacts for hot carrier solar cells. 2017 IEEE 44th Photovoltaic Specialist Conference (PVSC), pp. 696-700. doi:10.1109/PVSC.2017.8366687
    7. Dixit R, Barut B, Yin S, Nathawat J, Randle M, Arabchigavkani N, Kwan K He C-P, Mishima T D, Santos M B, Ferry D K, Sellers I R, and Bird J P, 2020. Pulsed studies of intervalley transfer in Al0.35In0.65As: a paradigm for valley photovoltaics. Phys. Rev. Mater. 4: 1-8. doi:10.1103/PhysRevMaterials.4.085404
    8. Frydendahl C, Grajower M and Bar-David J, 2020. Giant enhancement of silicon plasmonic shortwave infrared photodetection using nanoscale self-organized metallic films. Optica. 7: 371-379. doi:10.1364/OPTICA.379549
    9. Konovalov I and Ploss B, 2019. Modeling of hot carrier solar cell with semi-infinite energy filtering. Sol. Energy. 185: 59-63. doi:10.1016/j.solener.2019.04.050
    10. Shayan S, Matloub S and Rostami A, 2018. Efficiency enhancement in a single bandgap silicon solar cell considering hot-carrier extraction using selective energy contacts. Opt. Express. 29: 5068-5080. doi:10.1364/OE.416932
    11. Esgandari M, Barzinjy A A, Rostami A, Rostami G and Dolatyari M, 2022. Solar cells efficiency enhancement using multilevel selective energy contacts (SECs). Opt. Quantum Electron. 54: 1-9. doi:10.1007/s11082-021-03493-8
    12. Harada Y, Iwata N, Watanabe D, Asahi Sh and Kita T, 2019. Hot-carrier extraction in InAs/GaAs quantum dot superlattice solar cells. Hot-carrier extraction in InAs/GaAs quantum dot superlattice solar cells. IEEE 46th Photovoltaic Specialists Conference (PVSC), 2019, pp. 3004-3006. doi:10.1109/PVSC40753.2019.8980816
    13. Nguyen D-T, Lombez L, Gibelli F, Boyer-Richard S, Le Corre A, Durand O and Guillemoles J-F, 2018. Quantitative experimental assessment of hot carrier-enhanced solar cells at room temperature. Nature Energy. 3: 236-242. doi:10.1038/s41560-018-0106-3
    14. Liu Ch, Lu Y, Shen R, Dai Y, Yu X, Liu K and Lin Sh, 2022. Dynamics and physical process of hot carriers in optoelectronic devices. Nature Energy. 95: 1-25. doi:10.1016/j.nanoen.2022.106977
    15. Ašmontas S, Maldutis E and Širmulis E, 1988. CO2 Laser radiation detection by carrier heating in inhomogeneous semiconductors. Int. J. Optoelectron. 3: 263-266.
    16. Ašmontas S., Gradauskas J., Seliuta D. and Širmulis E. 1999. Photoresponse in nonuniform semiconductor junctions under infrared laser excitation. Proc. SPIE 3890, Fourth International Conference on Material Science and Material Properties for Infrared Optoelectronics, (4 November 1999); 3890:125-131. doi:10.1117/12.368343
    17. Umeno M, Sugito Y, Jimbo T, Hattori H and Amenixa Y, 1978. Hot photo-carrier and hot electron effects in p-n junctions. Sol. State Electron. 21: 191-195. doi:10.1016/0038-1101(78)90137-5
    18. Encinas-Sanz F and Guerra J M, 2003. Laser-induced hot carrier photovoltaic effects in semiconductor junctions. Prog. Quant. Electron. 27: 267-294. doi:10.1016/S0079-6727(03)00002-8
    19. Ašmontas S, Gradauskas J, Seliuta D and Širmulis E, 2000. Photoelectrical properties of nonuniform semiconductor under infrared laser radiation. Nonresonant Laser-Matter Interaction (NLMI-10), (26 June 2001). 4423: 18-27. doi:10.1117/12.431223
    20. Ašmontas S, Gradauskas J, Seliuta D, Sužiedelis A, Širmulis E, Valušis G and Tetyorkin V V, 2002. CO2 laser induced hot carrier photoeffect in HgCdTe. Materials Science Forum. 384-385: 147-150. doi:10.4028/www.scientific.net/MSF.384-385.147
    21. Ašmontas S, Gradauskas J, Sužiedelis A, Šilenas A, Širmulis E, Švedas V, Vaicikauskas V and Žalys O, 2018. Hot carrier impact on photovoltage formation in solar cells. Appl. Phys. Lett. 113: 071103-071106. doi:10.1063/1.5043155
    22. Sven R, 2016. Tabulated values of the Shockley-Queisser limit for single junction solar cells. Sol. Energy. 130: 139-147. doi:10.1016/j.solener.2016.02.015
    23. Dargys A. and Kundrotas J. Handbook on physical properties of Ge, Si, GaAs and InP. Vilnius: Science and Encyclopedia Publishers, 1994.
    24. Adachi S, 1989. Optical dispersion relations for GaP, GaAs, GaSb, InP, InAs, InSb, AlxGa1−xAs, and In1−xGaxAsyP1−y. J. Appl. Phys. 66: 6030-6040. doi:10.1063/1.343580
    25. Green M A, 2008. Self-consistent optical parameters of intrinsic silicon at 300 K including temperature coefficients. Sol. Energy Mater. Sol. Cells. 92: 1305-1310. doi:10.1016/j.solmat.2008.06.009
    26. Gradauskas J, Ašmontas S, Sužiedėlis A, Šilėnas A, Vaičikauskas V, Čerškus A, Širmulis E, Žalys O, and Masalskyi O, 2020. Influence of hot carrier and thermal components on photovoltage formation across the p-n junction. Appl. Sci. 10: 1-8. doi:10.3390/app10217483
    27. Sasaki M, Negishi H and Inoue M, 1986. Pulsed laser-induced transient thermoelectric effects in silicon crystals. J. Appl. Phys. 59: 796-802. doi:10.1063/1.336600
    28. Jayaraman S and Lee C H, 1972. Observation of two-photon conductivity in GaAs with nanosecond and picosecond light pulses. Appl. Phys. Lett. 20: 392-395. doi:10.1063/1.1653989
    Практично досягнута ефективність перетворення енергії одноперехідного сонячного елемента все ще значно нижча від теоретичної межі Шоклі-Квайссера і зростає дуже повільно з наступними роками. Ми вводимо явище гарячих носіїв як додатковий фундаментальний механізм власних втрат, який, як передбачається, відповідає за практичну недосяжність теоретичної межі ефективності. Всі сонячні фотони, крім тих, енергія яких дорівнює ширині забороненої зони напівпровідника, беруть участь у нагріванні носіїв і забезпечують цей процес більш ніж 52% всієї сонячної енергії. Ми також показуємо експериментальні доводи фотонапруги (ФН) гарячих носіїв у елементах з Si та GaAs яка зростає ще до процесу термалізації. Ця ФН протидіє класичній фотонапрузі, викликаній генерацією носіїв, та таким чином наноситься безпосередня втрата ефективності сонячного елемента з p-n переходом.

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