In this work, vanadium metal-organic framework derived VOx/carbon and VOx/N-doped carbon nanocomposites are presented. The methodology introduced here is based on a novel polyol synthesis of vanadium metal-organic frameworks (MOFs) involving a microwave-assisted solvothermal reaction of vanadyl acetylacetonate with biphenyl-4,4'-dicarboxylic acid (Bpdc) and/or 2,2'-bipyridine-4,4'-dicarboxylic acid (NBpdc) in diethylene glycol (DEG) at the temperature of 230 degrees C. The V-based MOFs, labeled as V-Bpdc and V-NBpdc, were used as precursors for the preparation of VOx/carbon and VOx/N-doped carbon nanocomposites with unique sponge-like nano-sheet and paperclip-like morphology, respectively. The nanocomposites were obtained via thermal transformation of as-prepared vanadium MOFs in the argon atmosphere at 600 degrees C. The VOx/carbon sample consists of nano-sheets with the thickness 5-20 nm while the VOx/N-doped carbon paperclip-like nanocomposite has a rod diameter 35-70 nm. It was found that the approach reported here provides an effective and simple preparation pathway of carbon-based nanocomposites containing homogeneously distributed VOx species. Both V-MOFs and V-MOF-derived nanocomposites were characterized by the variety of physicochemical methods. In the following step, the obtained nanocomposites were investigated as electrode materials in sodium-ion batteries. Based on the obtained results, high electrochemical activities of VOx/carbon and VOx/N-doped carbon nanocomposites were evidenced. Particularly, in the case of VOx/N-doped carbon-based electrode, high capacity and low irreversible capacity were achieved. Therefore, reported materials are found to be promising candidates for electrode materials in sodium-ion batteries.FEKT-S-20-6206; INTER-TRANSFER LTT19001, RP/CPS/2020/006; Ministerstvo Školství, Mládeže a Tělovýchovy, MŠMT: LM2018110, LM2018127; Central European Institute of Technology, CEITEC; European Regional Development Fund, ERDF: CZ.1.05/2.1.00/19.0409; Masarykova Univerzita, MUMinistry of Education, Youth and Sports of the Czech Republic-Program NPU I [LO1504]; DKRVO [RP/CPS/2020/006]; INTER-TRANSFER [LTT19001]; Operational Program Research and Development for Innovations - European Regional Development Fund; national budget of the Czech Republic [CZ.1.05/2.1.00/19.0409]; BUT specific research program [FEKT-S-20-6206]; MEYS CR [LM2018127, LM2018110
