Issue

Vol. 17 (2025)

Specific Sn–O–Fe Active Sites from Atomically Sn-Doping Porous Fe2O3 for Ultrasensitive NO2 Detection

https://doi.org/10.1007/s40820-025-01770-9
Yihong Zhong
Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon‑Based Functional Materials and Devices Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Soochow University, Suzhou 215123, People’s Republic of China
Guotao Yuan
College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, People’s Republic of China
Dequan Bao
The Key Laboratory of Rare Earth Functional Materials and Applications, Zhoukou Normal University, Zhoukou 466000, People’s Republic of China
Yi Tao
Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon‑Based Functional Materials and Devices Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Soochow University, Suzhou 215123, People’s Republic of China
Zhenqiu Gao
Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon‑Based Functional Materials and Devices Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Soochow University, Suzhou 215123, People’s Republic of China
Wei Zhao
Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon‑Based Functional Materials and Devices Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Soochow University, Suzhou 215123, People’s Republic of China
Shuo Li
Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon‑Based Functional Materials and Devices Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Soochow University, Suzhou 215123, People’s Republic of China
Yuting Yang
Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon‑Based Functional Materials and Devices Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Soochow University, Suzhou 215123, People’s Republic of China
Pingping Zhang
Suzhou Huiwen Nanotechnology Co., Ltd., Suzhou 215000, People’s Republic of China
Hao Zhang
Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon‑Based Functional Materials and Devices Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Soochow University, Suzhou 215123, People’s Republic of China
Xuhui Sun
Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon‑Based Functional Materials and Devices Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Soochow University, Suzhou 215123, People’s Republic of China

Corresponding Author: Xuhui Sun

xhsun@suda.edu.cn

Nano-Micro Letters, Vol. 17 (2025), Article Number: 276

Abstract

Conventional gas sensing materials (e.g., metal oxides) suffer from deficient sensitivity and serve cross-sensitivity issues due to the lack of efficient adsorption sites. Herein, the heteroatom atomically doping strategy is demonstrated to significantly enhance the sensing performance of metal oxides-based gas sensing materials. Specifically, the Sn atoms were incorporated into porous Fe2O3 in the form of atomically dispersed sites. As revealed by X-ray absorption spectroscopy and atomic-resolution scanning transmission electron microscopy, these Sn atoms successfully occupy the Fe sites in the Fe2O3 lattice, forming the unique Sn–O–Fe sites. Compared to Fe–O–Fe sites (from bare Fe2O3) and Sn–O–Sn sites (from SnO2/Fe2O3 with high Sn loading), the Sn–O–Fe sites on porous Fe2O3 exhibit a superior sensitivity (Rg/Ra = 2646.6) to 1 ppm NO2, along with dramatically increased selectivity and ultra-low limits of detection (10 ppb). Further theoretical calculations suggest that the strong adsorption of NO2 on Sn–O–Fe sites (N atom on Sn site, O atom on Fe site) contributes a more efficient gas response, compared to NO2 on Fe–O–Fe sites and other gases on Sn–O–Fe sites. Moreover, the incorporated Sn atoms reduce the bandgap of Fe2O3, not only facilitating the electron release but also increasing the NO2 adsorption at a low working temperature (150 °C). This work introduces an effective strategy to construct effective adsorption sites that show a unique response to specific gas molecules, potentially promoting the rational design of atomically modified gas sensing materials with high sensitivity and high selectivity.


Highlights:
1 The heteroatom atomically doping strategy was reported to construct highly efficient sites on metal oxides for the detection of low-concentration gas.
2 The atomically dispersed Sn atoms were intentionally incorporated into the Fe2O3 lattice during the oxidative annealing of Fe-based metal organic framework, leading to specific Sn–O–Fe sites, porous structures, and abundant oxygen vacancies.
3 The optimized Sn-Fe2O3 exhibited exceptional sensing performance for NO2 detection: ultra-high sensitivity (Rg/Ra=2646.6 to 1 ppm NO2), ultra-low limit of detection (10 ppb), and high selectivity.

Keywords

Atomically doping Specific Sn–O–Fe sites NO2 detection Gas sensor Specific adsorption
Zhong, Yihong, Guotao Yuan, Dequan Bao, Yi Tao, Zhenqiu Gao, Wei Zhao, Shuo Li, Yuting Yang, Pingping Zhang, Hao Zhang, and Xuhui Sun. 2025. “Specific Sn–O–Fe Active Sites from Atomically Sn-Doping Porous Fe2O3 for Ultrasensitive NO2 Detection”. Nano-Micro Letters 17 (May):276. https://doi.org/10.1007/s40820-025-01770-9.
Download Citation
Endnote/Zotero/Mendeley (RIS)
BibTeX
References
  1. A. Sharma, S.B. Eadi, H. Noothalapati, M. Otyepka, H.-D. Lee et al., Porous materials as effective chemiresistive gas sensors. Chem. Soc. Rev. 53(5), 2530–2577 (2024). https://doi.org/10.1039/D2CS00761D
  2. B. Zong, S. Wu, Y. Yang, Q. Li, T. Tao et al., Smart gas sensors: recent developments and future prospective. Nano-Micro Lett. 17(1), 54 (2024). https://doi.org/10.1007/s40820-024-01543-w
  3. F. Zheng, H.-Y. Jiang, X.-T. Yang, J.-H. Guo, L. Sun et al., Reviews of wearable healthcare systems based on flexible gas sensors. Chem. Eng. J. 490, 151874 (2024). https://doi.org/10.1016/j.cej.2024.151874
  4. P. Wu, Y. Li, A. Yang, X. Tan, J. Chu et al., Advances in 2D materials based gas sensors for industrial machine olfactory applications. ACS Sens. 9(6), 2728–2776 (2024). https://doi.org/10.1021/acssensors.4c00431
  5. G. Verma, A. Gokarna, H. Kadiri, K. Nomenyo, G. Lerondel et al., Multiplexed gas sensor: fabrication strategies, recent progress, and challenges. ACS Sens. 8(9), 3320–3337 (2023). https://doi.org/10.1021/acssensors.3c01244
  6. M. Taheri, I.A. Deen, M. Packirisamy, M.J. Deen, Metal oxide-based electrical/electrochemical sensors for health monitoring systems. TrAC Trends Anal. Chem. 171, 117509 (2024). https://doi.org/10.1016/j.trac.2023.117509
  7. M.J. Cooper, R.V. Martin, M.S. Hammer, P.F. Levelt, P. Veefkind et al., Global fine-scale changes in ambient NO2 during COVID-19 lockdowns. Nature 601(7893), 380–387 (2022). https://doi.org/10.1038/s41586-021-04229-0
  8. T. Xue, M. Tong, M. Wang, X. Yang, Y. Wang et al., Health impacts of long-term NO2 exposure and inequalities among the Chinese population from 2013 to 2020. Environ. Sci. Technol. 57(13), 5349–5357 (2023). https://doi.org/10.1021/acs.est.2c08022
  9. M. Krzyzanowski, A. Cohen, Update of WHO air quality guidelines. Air Qual. Atmos. Health 1(1), 7–13 (2008). https://doi.org/10.1007/s11869-008-0008-9
  10. L.X. Ou, M.Y. Liu, L.Y. Zhu, D.W. Zhang, H.L. Lu, Recent progress on flexible room-temperature gas sensors based on metal oxide semiconductor. Nano-Micro Lett. 14(1), 206 (2022). https://doi.org/10.1007/s40820-022-00956-9
  11. S. Ma, J. Xu, Nanostructured metal oxide heterojunctions for chemiresistive gas sensors. J. Mater. Chem. A 11(44), 23742–23771 (2023). https://doi.org/10.1039/d3ta04953a
  12. Q. Li, W. Zeng, Y. Li, Metal oxide gas sensors for detecting NO2 in industrial exhaust gas: recent developments. Sens. Actuat. B Chem. 359, 131579 (2022). https://doi.org/10.1016/j.snb.2022.131579
  13. C. Zhu, S. Fu, Q. Shi, D. Du, Y. Lin, Single-atom electrocatalysts. Angew. Chem. Int. Ed. 56(45), 13944–13960 (2017). https://doi.org/10.1002/anie.201703864
  14. Q. Zhang, J. Guan, Single-atom catalysts for electrocatalytic applications. Adv. Funct. Mater. 30(31), 2000768 (2020). https://doi.org/10.1002/adfm.202000768
  15. N. Cheng, L. Zhang, K. Doyle-Davis, X. Sun, Single-atom catalysts: from design to application. Electrochem. Energy Rev. 2(4), 539–573 (2019). https://doi.org/10.1007/s41918-019-00050-6
  16. S. Ji, Y. Chen, X. Wang, Z. Zhang, D. Wang et al., Chemical synthesis of single atomic site catalysts. Chem. Rev. 120(21), 11900–11955 (2020). https://doi.org/10.1021/acs.chemrev.9b00818
  17. Y. Chen, S. Ji, C. Chen, Q. Peng, D. Wang et al., Single-atom catalysts: synthetic strategies and electrochemical applications. Joule 2(7), 1242–1264 (2018). https://doi.org/10.1016/j.joule.2018.06.019
  18. C. Kim, H. Min, J. Kim, J.H. Moon, Boosting electrochemical methane conversion by oxygen evolution reactions on Fe–N–C single atom catalysts. Energy Environ. Sci. 16(7), 3158–3165 (2023). https://doi.org/10.1039/D3EE00027C
  19. F. Gu, Y. Cui, D. Han, S. Hong, M. Flytzani-Stephanopoulos et al., Atomically dispersed Pt (II) on WO3 for highly selective sensing and catalytic oxidation of triethylamine. Appl. Catal. B Environ. 256, 117809 (2019). https://doi.org/10.1016/j.apcatb.2019.117809
  20. B. Feng, Z. Wang, Y. Feng, P. Li, Y. Zhu et al., Single-atom Au-functionalized mesoporous SnO2 nanospheres for ultrasensitive detection of Listeria monocytogenes biomarker at low temperatures. ACS Nano 18(34), 22888–22900 (2024). https://doi.org/10.1021/acsnano.4c03566
  21. P. Wang, S. Guo, Z. Hu, L. Zhou, T. Li et al., Single-atom Cu stabilized on ultrathin WO2.72 nanowire for highly selective and ultrasensitive ppb-level toluene detection. Adv. Sci. 10(26), 2302778 (2023). https://doi.org/10.1002/advs.202302778
  22. T. Chu, C. Rong, L. Zhou, X. Mao, B. Zhang et al., Progress and perspectives of single-atom catalysts for gas sensing. Adv. Mater. 35(3), 2206783 (2023). https://doi.org/10.1002/adma.202206783
  23. G. Lei, H. Pan, H. Mei, X. Liu, G. Lu et al., Emerging single atom catalysts in gas sensors. Chem. Soc. Rev. 51(16), 7260–7280 (2022). https://doi.org/10.1039/d2cs00257d
  24. M.-H. Pham, G.-T. Vuong, A.-T. Vu, T.-O. Do, Novel route to size-controlled Fe-MIL-88B-NH2 metal-organic framework nanocrystals. Langmuir 27(24), 15261–15267 (2011). https://doi.org/10.1021/la203570h
  25. C. Serre, F. Millange, S. Surblé, G. Férey, A route to the synthesis of trivalent transition-metal porous carboxylates with trimeric secondary building units. Angew. Chem. Int. Ed. 43(46), 6285–6289 (2004). https://doi.org/10.1002/anie.200454250
  26. V. Pascanu, A. Bermejo Gómez, C. Ayats, A.E. Platero-Prats, F. Carson et al., Double-supported silica-metal–organic framework palladium nanocatalyst for the aerobic oxidation of alcohols under batch and continuous flow regimes. ACS Catal. 5(2), 472–479 (2015). https://doi.org/10.1021/cs501573c
  27. W. Tian, J. Han, L. Wan, N. Li, D. Chen et al., Enhanced piezocatalytic activity in ion-doped SnS2 via lattice distortion engineering for BPA degradation and hydrogen production. Nano Energy 107, 108165 (2023). https://doi.org/10.1016/j.nanoen.2023.108165
  28. J. Łuczak, M. Kroczewska, M. Baluk, J. Sowik, P. Mazierski et al., Morphology control through the synthesis of metal-organic frameworks. Adv. Colloid Interface Sci. 314, 102864 (2023). https://doi.org/10.1016/j.cis.2023.102864
  29. H. Yuan, N. Li, W. Fan, H. Cai, D. Zhao, Metal-organic framework based gas sensors. Adv. Sci. 9(6), 2104374 (2022). https://doi.org/10.1002/advs.202104374
  30. J. Deng, S. Cai, M. Gao, J.-Y. Hasegawa, H. Yao et al., Crystal-in-amorphous vanadate catalysts for universal poison-resistant elimination of nitric oxide. ACS Catal. 13(18), 12363–12373 (2023). https://doi.org/10.1021/acscatal.3c02571
  31. A.M. Jubb, H.C. Allen, Vibrational spectroscopic characterization of hematite, maghemite, and magnetite thin films produced by vapor deposition. ACS Appl. Mater. Interfaces 2(10), 2804–2812 (2010). https://doi.org/10.1021/am1004943
  32. A.K. Bhunia, B. Mahata, B. Mandal, P.K. Guha, S. Saha, Emerging 2D nanoscale metal oxide sensor: semiconducting CeO2 nano-sheets for enhanced formaldehyde vapor sensing. Nanotechnology 35(45), 455501 (2024). https://doi.org/10.1088/1361-6528/ad6e8b
  33. W. Chen, S. Yang, H. Liu, F. Huang, Q. Shao et al., Single-atom Ce-modified α-Fe2O3 for selective catalytic reduction of NO with NH3. Environ. Sci. Technol. 56(14), 10442–10453 (2022). https://doi.org/10.1021/acs.est.2c02916
  34. L. Zhao, C. Yu, C. Xin, Y. Xing, Z. Wei et al., Increasing the catalytic activity of Co3O4 via boron doping and chemical reduction for enhanced acetone detection. Adv. Funct. Mater. 34(18), 2314174 (2024). https://doi.org/10.1002/adfm.202314174
  35. L. Gui, Z. Wang, K. Zhang, B. He, Y. Liu et al., Oxygen vacancies-rich Ce0.9Gd0.1O2-δ decorated Pr0.5Ba0.5CoO3-δ bifunctional catalyst for efficient and long-lasting rechargeable Zn-air batteries. Appl. Catal. B Environ. 266, 118656 (2020). https://doi.org/10.1016/j.apcatb.2020.118656
  36. B. Mandal, A.K. Bhunia, B. Mahata, S. Roy, S. Acharyya et al., Defect-rich SnO2–x polydisperse spheres toward the detection of vehicle-emitted category NO2 gas. IEEE Sens. J. 24(17), 27183–27190 (2024). https://doi.org/10.1109/JSEN.2024.3429543
  37. H. Xie, Y. Song, Y. Jiao, L. Gao, S. Shi et al., Engineering surface passivation and hole transport layer on hematite photoanodes enabling robust photoelectrocatalytic water oxidation. ACS Nano 18(7), 5712–5722 (2024). https://doi.org/10.1021/acsnano.3c11638
  38. A.K. Bhunia, B. Mandal, P.K. Guha, Efficient ethanol sensor based on vertically aligned ZnO nanorods on radio frequency sputtered ZnO/Pt/SiO2/Si substrate. Phys. Status Solidi RRL 19(3), 2400285 (2025). https://doi.org/10.1002/pssr.202400285
  39. Y. Hong, L. Wei, Q. Zhang, Z. Deng, X. Liao et al., A broad-spectrum gas sensor based on correlated two-dimensional electron gas. Nat. Commun. 14(1), 8496 (2023). https://doi.org/10.1038/s41467-023-44331-7
  40. T. Liang, Y. Li, X. Zhang, H. Bao, F. Li et al., Selenium-doped hematite (α-Fe2O3) hollow nanorods for highly sensitive and selective detection of trace NO2. J. Mater. Chem. C 13(13), 6660–6668 (2025). https://doi.org/10.1039/d4tc05464d
  41. A. Mirzaei, K. Janghorban, B. Hashemi, M. Bonyani, S.G. Leonardi et al., A novel gas sensor based on Ag/Fe2O3 core-shell nanocomposites. Ceram. Int. 42(16), 18974–18982 (2016). https://doi.org/10.1016/j.ceramint.2016.09.052
  42. L. Sun, J. Sun, K. Zhang, X. Sun, S. Bai et al., rGO functionalized α-Fe2O3/Co3O4 heterojunction for NO2 detection. Sens. Actuat. B Chem. 354, 131194 (2022). https://doi.org/10.1016/j.snb.2021.131194
  43. S.L. Bai, K. Tian, H. Fu, Y.J. Feng, R.X. Luo et al., Novel α-Fe2O3/BiVO4 heterojunctions for enhancing NO2 sensing properties. Sens. Actuat. B-Chem. 268, 136–143 (2018). https://doi.org/10.1016/j.snb.2018.03.173
  44. B. Zhang, G. Liu, M. Cheng, Y. Gao, L. Zhao et al., The preparation of reduced graphene oxide-encapsulated α-Fe2O3 hybrid and its outstanding NO2 gas sensing properties at room temperature. Sens. Actuat. B Chem. 261, 252–263 (2018). https://doi.org/10.1016/j.snb.2018.01.143
  45. Y.-C. Liang, Y.-W. Hsu, Enhanced sensing ability of brush-like Fe2O3-ZnO nanostructures towards NO2 gas via manipulating material synergistic effect. Int. J. Mol. Sci. 22(13), 6884 (2021). https://doi.org/10.3390/ijms22136884
  46. C. Han, X. Li, Y. Liu, X. Li, C. Shao et al., Construction of In2O3/ZnO yolk-shell nanofibers for room-temperature NO2 detection under UV illumination. J. Hazard. Mater. 403, 124093 (2021). https://doi.org/10.1016/j.jhazmat.2020.124093
  47. Y. Yang, M. Zhu, H. Zhang, B. Wang, C. Chen et al., Room temperature gas sensor based on rGO/Bi2S3 heterostructures for ultrasensitive and rapid NO2 detection. Chem. Eng. J. 490, 151872 (2024). https://doi.org/10.1016/j.cej.2024.151872
  48. G.-C. Lu, X.-H. Liu, W. Zheng, J.-Y. Xie, Z.-S. Li et al., UV-activated single-layer WSe2 for highly sensitive NO2 detection. Rare Met. 41(5), 1520–1528 (2022). https://doi.org/10.1007/s12598-021-01899-7
  49. H. Ji, W. Zeng, Y. Li, Gas sensing mechanisms of metal oxide semiconductors: a focus review. Nanoscale 11(47), 22664–22684 (2019). https://doi.org/10.1039/c9nr07699a
  50. G.-L. Chen, M.-S. Lv, L.-L. Sui, Z.-P. Deng, Y.-M. Xu et al., Low-temperature and dual-sensing NO2/dimethylamine sensor based on single-crystal WO3 nanops-supported sheets synthesized by simple pyrolysis of spoiled WCl6 powder. Chem. Eng. J. 464, 142528 (2023). https://doi.org/10.1016/j.cej.2023.142528
  51. M. Al-Hashem, S. Akbar, P. Morris, Role of oxygen vacancies in nanostructured metal-oxide gas sensors: a review. Sens. Actuat. B Chem. 301, 126845 (2019). https://doi.org/10.1016/j.snb.2019.126845
  52. C. Zhang, G. Liu, X. Geng, K. Wu, M. Debliquy, Metal oxide semiconductors with highly concentrated oxygen vacancies for gas sensing materials: a review. Sens. Actuat. A Phys. 309, 112026 (2020). https://doi.org/10.1016/j.sna.2020.112026
Read More
Author biographies are not available.
Download this PDF file
PDF SUPPLEMENTARY FILE
Statistic
Read Counter : 735 Download : 556

Most read articles by the same author(s)

1 2 3 > >>