Bio-Inspired Ordered WO₃ Nano-Helixes Enable Multi-Band Electrochromic Smart Windows with Ultrafast Switching and Robust Cyclability

Abstract

Multi-band electrochromic (MBEC) smart windows, capable of dynamic and selective management of solar radiation (visible and near-infrared transmittance) and thermal radiation (mid- and long-wave infrared emissivity), are crucial for zero-energy buildings and adaptive optical systems. However, they have not yet been developed due to the inherent material design challenges and kinetics-stability trade-offs. Inspired by lotus root vessels, we develop vertically aligned nano-helix tungsten oxide (NH-WO₃) films with amorphous-crystalline heterophase. The multiscale microstructure provides numerous active sites, enhances local electric fields, and alleviates stress during repeated cycling. Consequently, NH-WO₃ achieves unprecedented quad-band electrochromic performances with multi-mode photothermal modulation across the visible to long-wave infrared spectra, featuring large optical contrast (ΔT_VIS–NIR ~79%), significant temperature and emissivity variation (ΔT = 9.3 °C, Δε = 0.47@5 μm), ultrafast switching (3.9/1.9 s@780 nm, 2.8/2.5 s@990 nm), and robust cyclability (10 000 cycles with only 9.1% optical-contrast loss). Furthermore, a prototype smart window based on the NH-WO₃ film maintains a comfortable indoor temperature of 26 °C even under continuous AM 1.5G solar irradiation for 1 hour. This bio-inspired nano-helix design provides an efficient strategy for the development of advanced next-generation photothermal management smart windows toward practical energy-efficient architectures and adaptive optics.

Keywords

dynamic solar and thermal management / high stability / nano-helix tungsten oxide / quad-band electrochromism / ultrafast response

References

[1] Z. Mei, Y. Ding, M. Wang, P. S. Lee, A. Pawlicka, L. Zhao, X. diao, Adv. Mater. 2025, 37, 2420578.

[2] Q. Meng, S. Cao, J. Guo, Q. Wang, K. Wang, T. Yang, R. Zeng, J. Zhao, B. Zou, J. Energy Chem. 2023, 77, 137.

[3] S. Zhang, S. Cao, T. Zhang, A. Fisher, J. Y. Lee, Energy Environ. Sci. 2018, 11, 2884.

[4] S. Zhang, S. Cao, T. Zhang, J. Y. Lee, Adv. Mater. 2020, 32, 2004686.

[5] F. Zhao, B. Wang, B. Huang, W. Zhang, J. Chen, L. Liu, H. Wang, A. Y. Elezzabi, P. S. Lee, D. J. Milliron, Nat. Rev. Clean Technol 2025, 1, 396.

[6] M. K. Ganesha, H. Hakkeem, I. Mondal, A. K. Singh, G. U. Kulkarni, Small 2024, 20, 2405467.

[7] M. K. Ganesha, I. Mondal, A. K. Singh, G. U. Kulkarni, ACS Appl. Mater. Interfaces 2023, 15, 19111.

[8] M. K. Ganesha, H. Hakkeem, A. K. Singh, Small 2024, 20, 2403156.

[9] S. Cao, S. Zhang, T. Zhang, Q. Yao, J. Y. Lee, Joule 2019, 3, 1152.

[10] M. Chen, X. Zhang, D. Yan, J. Deng, W. Sun, Z. Li, Y. Xiao, Z. Ding, J. Zhao, Y. Li, Mater. Horiz. 2023, 10, 2191.

[11] Y. Huang, S. Wu, S. Zhao, Z. Guo, Z. Zhao, X. Wu, B. Wang, F. Wang, A. Xi, F. Lan, Energy Environ. Sci. 2025, 18, 1824.

[12] Y. Zhou, Y. Lv, X. Guo, X. Wang, Z. Liu, J. Wang, Q. Sui, J. Wang, Z. Zeng, G. Cai, Adv. Mater. 2025, 37, 2502706.

[13] J. Wang, Z. Wang, L. Cui, M. Zhang, X. Huo, M. Guo, Adv. Mater. 2024, 36, 2406939.

[14] J. Wang, Z. Wang, M. Zhang, X. Huo, M. Guo, Chem. Eng. J. 2024, 484, 149628.

[15] J. Wang, Y. Zhou, Y. Lv, J. f. Feng, Z. Wang, G. Cai, Small 2024, 20, 2310229.

[16] Y. Wang, Z. Gong, Y. Zeng, H. Zhao, J. Yang, Chem. Eng. J. 2022, 431, 134066.

[17] Y. Zhai, J. Li, S. Shen, Z. Zhu, S. Mao, X. Xiao, C. Zhu, J. Tang, X. Lu, J. Chen, Adv. Funct. Mater. 2022, 32, 2109848.

[18] M. Barawi, L. De Trizio, R. Giannuzzi, G. Veramonti, L. Manna, M. Manca, ACS Nano 2017, 11, 3576.

[19] J. Kim, G. K. Ong, Y. Wang, G. Leblanc, T. E. Williams, T. M. Mattox, B. A. Helms, D. J. Milliron, Nano Lett. 2015, 15, 5574.

[20] Z. Wang, Q. Zhang, S. Cong, J. Zhao, M. Yang, Z. Zheng, S. Zeng, X. Yang, F. Geng, Z. Zhao, Adv Opt Mater 2017, 5, 1700194.

[21] T. Chen, X. Mai, Y. Li, T. Wang, R. Gong, F. Chen, H. Huang, Z. Yan, F. Wang, Chem. Eng. J. 2024, 499, 155999.

[22] Z. Huang, Y. Peng, J. Zhao, S. Zhang, P. Qi, F. Yan, B. Ding, Y. Xuan, X. Zhang, Nano-Micro Lett. 2024, 17, 98.

[23] K. Li, Y. Shao, H. Yan, Z. Lu, K. J. Griffith, J. Yan, G. Wang, H. Fan, J. Lu, W. Huang, B. Bao, X. Liu, C. Hou, Q. Zhang, Y. Li, J. Yu, H. Wang, Nat. Commun. 2018, 9, 4798.

[24] P. Pattathil, R. Scarfiello, R. Giannuzzi, G. Veramonti, T. Sibillano, A. Qualtieri, C. Giannini, P. D. Cozzoli, M. Manca, Nanoscale 2016, 8, 20056.

[25] Z. Shao, A. Huang, C. Cao, X. Ji, W. Hu, H. Luo, J. Bell, P. Jin, R. Yang, X. Cao, Nat. Sustain 2024, 7, 796.

[26] Y. Zeng, Y. Liu, T. Jiang, F. Zhao, L. Wang, S. Ma, G. Yang, S. Han, G. Lai, G. Tan, G. Han, Adv. Mater. 2025,

[27] Y. Ding, Z. Mei, X. Wu, W. Zhang, Y. Zhang, A. Xi, D. Gao, F. Lan, J. Xu, X. Diao, R. Zhang, Adv. Funct. Mater. 2025, 35, 2500122.

[28] K. Kamata, S. Suzuki, M. Ohtsuka, M. Nakagawa, T. Iyoda, A. Yamada, Adv. Mater. 2011, 23, 5509.

[29] D. Nepal, S. Kang, K. M. Adstedt, K. Kanhaiya, M. R. Bochstaller, L. C. Brinson, M. J. Buehler, P. V. Coveney, K. Dayal, J. A. El-awady, L. C. Henderson, D. L. Kaplan, Nat. Mater. 2022, 22, 18.

[30] R. Schneider, K. v. t. Klooster, K. L. Picard, J. V. Gucht, T. Demura, M. Janson, A. Sampathkumar, E. E. Deinum, T. Ketelaar, S. Persson, Nat. Commun. 2021, 12, 699.

[31] M. Sabelfeld, S.-U. Geißen, J. Membr. Sci. 2019, 574, 222.

[32] J. Wang, T. Fan, X. Li, X. Hu, W. Huang, W. Yuan, Z. Lin, Matter 2022, 5, 4396.

[33] Z. Zhang, B. Cui, Y. Sun, J. Shan, S. Li, S. Hao, W. Shan, W. Wang, Y. Song, Y. Fang, T. Liu, Adv. Mater. 2025, 37, 2501166.

[34] K. Ito, R. Uchida, K. Noda, J. Photochem. Photobiol. A Chem. 2023, 443, 114824.

[35] K. Shi, Z. Chen, W. Sun, Small 2024, 20, 2405769.

[36] K. Meng, J. Zhang, B. Cheng, X. Ren, Z. Xia, F. Xu, L. Zhang, J. Yu, Adv. Mater. 2024, 36, 2406460.

[37] B. Tu, J. Miao, R. Che, F. Wang, Y. Li, J. Li, J. Qiu, Sep. Purif. Technol. 2025, 352, 128188.

[38] J. Wang, G. Li, D. Luo, Y. Zhao, Y. Zhang, G. Zhou, L. Shui, X. Wang, J Mater Chem A 2021, 9, 11160.

[39] S. Zhang, X. Han, X. Liu, Z. Huang, P. Wang, S. Sheng, G. Wu, J. He, J. Guo, X. Zheng, H. Li, J. Liu, X. Hong, Adv. Mater. 2024, 36, 2410355.

[40] Y. Sun, P. Qiu, W. Yu, J. Li, H. Guo, L. Wu, H. Luo, R. Meng, Y. Zhang, S. F. Liu, Adv. Mater. 2021, 33, 2104330.

[41] K. Wei, T. Zhou, Y. Jiang, C. Sun, Y. Liu, S. Li, S. Liu, X. Fu, C. Hu, S. Tian, Y. Yang, X. Fu, N. Almasoud, M. H. Qaid, M. K. Nazeeruddin, H. Hsu, W. Li, J. T. Kim, R. Long, W. Zhang, J. Chen, M. Yuan, Nature 2025, 638, 949.

[42] Y. Ji, X. Zhao, Y. Pan, Z. Su, J. Lin, E. M. Akinoglu, Y. Xu, H. Zhang, P. Zhao, Y. Dong, X. Wei, F. Liu, P. Mulvaney, Adv. Funct. Mater. 2023, 33, 2211421.

[43] C. Sui, J. Pu, T.-H. Chen, J. Liang, Y. Lai, Y. Rao, R. Wu, Y. Han, K. Wang, X. Li, V. Viswanathan, P. Hsu, Nat. Sustain. 2023, 6, 428.

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2025 The Author(s). Energy & Environmental Materials published by John Wiley & Sons Australia, Ltd on behalf of Zhengzhou University.