Abstract
Silicon heterojunction (SHJ) solar cells are one of the most promising directions in the future photovoltaic industry. The limited supply of rare indium and the high cost of silver paste are among the most important problems that SHJ solar cells will face. To overcome the obstacle of indium-based transparent electrodes for efficient SHJ solar cells, here we successfully prepared cheap and mass-producible undoped tin oxide (SnOx) electrode materials by sputtering at room temperature. Taking advantage of its natural oxygen vacancy defect, the carrier mobility and resistivity of prepared materials reached 22 cm2 V−1 s−1 and 2.38 × 10−3 Ω cm, respectively. The SHJ solar cell with an undoped SnOx front transparent electrode demonstrated an efficiency of 24.91%. Furthermore, SnOx films have excellent chemical stability and can withstand corrosion by acid and alkali solutions during electroplating processes. Finally, SHJ solar cells with plating copper electrode and double-sided indium-based transparent electrodes halved were prepared, and a certified efficiency of 25.94% (total area of 274.4 cm2) was achieved.
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All data generated or analysed during this study are included in the published article and its Supplementary Information. Source data are provided with the paper. Any additional information is available from corresponding authors upon request.
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Acknowledgements
We thank L. Lv, H. Wu, C. He, Y. Sun and H. Wu for sample fabrication and testing. X.Z. acknowledges financial support from the National Natural Science Foundation of China (grant nos. U21A2072 and 62274099) and the Fundamental Research Funds for the Central Universities (Nankai University). J.Z. and X.C. acknowledge financial support from the Carbon Emission Peak and Carbon Neutrality Special Fund of Jiangsu Province (BA2022205). We acknowledge Haihe Laboratory of Sustainable Chemical Transformations.
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These authors contributed equally: C.Y. and Q.Z. G.D. and X.Z. conceived and directed the overall project. C.Y. and G.D. fabricated all the devices and conducted the characterization. V.A. prepared electroplated copper electrodes and carried out related work. Q.Z. characterized and analysed the materials with the assistance of G.D. and X.Z. Q.Z., Y.Z., X.R., C.-W.P., Q.W., V.A., X.C. and J.Z. contributed to useful discussions. C.Y., Q.Z., G.D. and X.Z. wrote the paper. All authors discussed the results and commented on the paper.
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C.Y., Q.W., Y.Z., X.R., G.D., C.-W.P., X.C. and J.Z. are employees of Suzhou Maxwell Technologies Co., Ltd. V.A. is an employee of SunDrive Solar Pty., Ltd. The other authors declare no competing interests.
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Optical characteristics, Tauc plot, XRD, XPS, PL and J–V data.
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XPS, electrical characteristics, J–V and EQE data.
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Photovoltaic parameter data.
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Yu, C., Zou, Q., Wang, Q. et al. Silicon solar cell with undoped tin oxide transparent electrode. Nat Energy 8, 1119–1125 (2023). https://doi.org/10.1038/s41560-023-01331-7
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DOI: https://doi.org/10.1038/s41560-023-01331-7