a, Elemental mapping (C, N, O) of CNT-SS using EDS (scale bar, 200 μm). b, SEM image of the crystal seeds wiped on the CNT-SS (scale bar, 1 μm). c, Raman spectra of CNT-SS with 300 s plasma treatment before and after LiXZM growth. The two peaks located at 1,351 and 1,580 cm−1 arise from the D and G bands of CNT-SS. The intensity ratio of the two peaks (ID/IG) remained approximately the same after the in situ growth of LiXZM, indicating that the structural integrity of the CNTs was preserved. d, XPS survey spectrum of C-LiXZM. XPS analysis of CNT-SS demonstrates the existence of C, O, and N on the surfaces of the CNTs, whereas peaks corresponding to Si 2p, Al 2p and Li 1s are observed in the XPS spectrum of C-LiXZM owing to the presence of LiX zeolite. e, XPS spectra of C-LiXZM in the C 1s region. The peaks at 284.6, 285.2, 287.3 and 289.0 eV correspond to C–C (sp3), C–N (sp3), C=O (sp2) and O–C=O (sp2), respectively. f, XPS spectra of C-LiXZM in the N 1s region. The peaks of pyridinic N at 398.6 eV, pyrrolic N at 399.7 eV and graphitic N at 401.1 eV are identified in the N 1s spectrum of C-LiXZM. g, Thermogravimetric curve of C-LiXZM after the stainless-steel mesh substrate was removed. The dehydration of zeolites (<200 °C)46 and the thermal decomposition of CNTs (500–630 °C)47 take place in sequence as the temperature increases. h, Cross-sectional SEM image of the interface between LiXZM and Li metal anode (scale bar, 100 μm).