Supporting Information. Metal-Organic Frameworks Mediated Synthesis of One-Dimensional Molybdenum-Based/Carbon Composites for Enhanced Lithium Storage

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1 Supporting Information Metal-Organic Frameworks Mediated Synthesis of One-Dimensional Molybdenum-Based/Carbon Composites for Enhanced Lithium Storage Wei Tian a, Han Hu b, Yixian Wang a, Peng Li c, Jingyan Liu a, Jialiang Liu a, Xiaobo Wang a, Xiangdong Xu a, Zhongtao Li a, Qingshan Zhao a, Hui Ning a, Wenting Wu a, Mingbo Wu a * a State Key Laboratory of Heavy Oil Processing, College of Chemical Engineering, China University of Petroleum (East China), Qingdao , China b Nanomaterials Centre, School of Chemical Engineering and Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St. Lucia, Queensland 4072, Australia c Department of Energy Engineering, Hanyang University, Seoul , Republic of Korea * wumb@upc.edu.cn 1

2 Figure S1. (a) XRD pattern, (b) SEM images of the as-prepared MoO3 nanorods. Figure S2. TEM images of Zn, Co-BMZIFs coated MoO3 nanorods obtained under different conditions. Many attempts have been made to achieve the controllable growth of Zn, Co-BMZIFs on surfaces of MoO3 nanorods. In previous attempts, it is found that Zn, Co-BMZIFs could not well grow on surfaces of MoO3 nanorods without the introduction of PVP (Figure S2a) and it would overgrows away from MoO3 nanorods 2

3 with the reaction time over 6 h (Figure S2b). Besides, the appropriate molar ratio between MoO3 and metal salts (Zn 2+, Co 2+ ) which act as the reactant of BMZIFs is also an important factor. As shown in Figure S2c, the BMZIFs shell is relatively thick if there is not enough MoO3 nanorods for the reaction. When the amount of MoO3 nanorods is exceedingly increased, the thickness of the BMZIFs shell gets thin and cannot fulfill the complete coating (Figure S2d). Figure S3. TEM images of MoO3@BMZIFs samples obtained with different reaction time. (a) 0.25 h, (b) 2 h. Figure S4. XRD patterns of (a) H-MoO2/C and (b) Mo2C/C

4 Table S1 The quantitative elemental analyses of different samples based on the CHN elemental analysis combined with ICP-AES measurement. Samples Elements (wt%) C N Mo Zn Co MoO2/C H-MoO2/C Mo2C/C Mo2C/C Figure S5. XPS survey scan spectra, high-resolution XPS spectra of Mo 3d and N 1s of (a, e, i) MoO2/C-600, (b, f, j) H-MoO2/C, (c, g, k) Mo2C/C-700 and (d, h, l) Mo2C/C-800, respectively. The high content of nitrogen on the skeleton of carbon matrixes is a favorable factor 4

5 to tune electronic properties and conductivity, further facilitating their applications especially in field of electrode materials. 1 Among these N functionalities, the presence of graphitic nitrogen will improve the electric conductivity effectively as it can bring extra free electrons. While other N atoms like pyrrolic and pyridinic N which are located at the edge of graphene layer can contribute to adsorbing the exotic atoms and significantly enhance the insertion capacity by providing more active sites. 2 Meanwhile, the content and constitute of nitrogen are greatly affected by the pyrolysis temperature, which the pyrrolic nitrogen is inclined to convert into pyridinic and graphitic ones with the increase of temperature as shown in Figure S5i-f. Figure S6. (a) EDX spectrum and (b) TEM image with corresponding elemental mapping of MoO2/C

6 Figure S7. (a) TEM image and (b) Long-term cycling performance of Mo2C/C-800. Figure S8. Discharge-charge curves of (a) MoO2/C-600, (b) H-MoO2/C and (c) Mo2C/C-700 at a current density of 0.1 A g -1. Figure S9. TEM images of different electrode materials (a) MoO2/C-600, (b,c) H-MoO2/C and (d) Mo2C/C-700 after 50 cycles at a current density of 1 A g -1. 6

7 Figure S10. (a) CV curves of MoO2/C-600 at different scan rates (b) b values plotted against battery potential of MoO2/C-600 for cathodic scans. The inset is the current response plotted against scan rates at various potentials. (c) The capacitive contribution to the reduction process shown by the shaded region at the scan rates of 1 mv s -1 for the MoO2/C-600 electrode. 7

8 Table S2 Comparison of the capacity of present work with the reported MoO2/C or Mo2C/C composites as anode materials for LIBs. Samples Current density (ma g -1 ) Cycle number Capacity (mah g -1 ) Ref. MoO2/C hollow spheres MoO2/ carbon microflowers MoO2 nanobelts@n-c MoO2/C aerogels MoO2/CNTs MoO2/Mo2C heteronanotubes MoO2/Mo2C/C spheres Mo2C/graphene Mo2C@onion-like carbon MoO2/C This work H- MoO2/C This work Mo2C/C This work 8

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