TY - JOUR
T1 - Synthesis of nitrogen-doped oxygen-deficient TiO2-x/reduced graphene oxide/sulfur microspheres via spray drying process for lithium-sulfur batteries
AU - Chen, Guifeng
AU - Li, Junhua
AU - Liu, Ning
AU - Zhao, Yan
AU - Tao, Junguang
AU - Kalimuldina, Gulnur
AU - Bakenov, Zhumabay
AU - Zhang, Yongguang
PY - 2019/12/5
Y1 - 2019/12/5
N2 - Improving sulfur redox kinetics and cycling stability of lithium-sulfur (Li-S) batteries through controlling inherent dissolution of polysulfides and following shuttle effect is pivotal for further progress of this promising electrochemical system. In this work, three-dimensional porous microspheres composed of nanosized sulfur particles, nitrogen-doped oxygen-deficient TiO2-x nanorods and reduced graphene oxide (N-TiO2-x/RGO/S) were synthesized as sulfur host material for the first time in spray-drying process. The microspheres construction with void spaces mitigated volumetric expansion upon charge/discharge cycling and improved sulfur utilization. Furthermore, the N-TiO2-x nanorods enhanced the conductivity of the material and exhibited strong capability for adsorption and the migration of lithium polysulfides, which was demonstrated by the density functional theory (DFT) calculations. Due to such advantages, the N-TiO2-x/RGO/S cathode delivered excellent rate capability and stable cycle performance at 1.0 C over 300 cycles with a specific capacity about 700 mAh g−1. This novel design and preparation strategy also contributes to the materials engineering and structural design towards remarkable improvement of electrochemical performance of energy storage systems.
AB - Improving sulfur redox kinetics and cycling stability of lithium-sulfur (Li-S) batteries through controlling inherent dissolution of polysulfides and following shuttle effect is pivotal for further progress of this promising electrochemical system. In this work, three-dimensional porous microspheres composed of nanosized sulfur particles, nitrogen-doped oxygen-deficient TiO2-x nanorods and reduced graphene oxide (N-TiO2-x/RGO/S) were synthesized as sulfur host material for the first time in spray-drying process. The microspheres construction with void spaces mitigated volumetric expansion upon charge/discharge cycling and improved sulfur utilization. Furthermore, the N-TiO2-x nanorods enhanced the conductivity of the material and exhibited strong capability for adsorption and the migration of lithium polysulfides, which was demonstrated by the density functional theory (DFT) calculations. Due to such advantages, the N-TiO2-x/RGO/S cathode delivered excellent rate capability and stable cycle performance at 1.0 C over 300 cycles with a specific capacity about 700 mAh g−1. This novel design and preparation strategy also contributes to the materials engineering and structural design towards remarkable improvement of electrochemical performance of energy storage systems.
KW - Lithium-sulfur batteries
KW - Nitrogen doped TiO
KW - Oxygen-deficient TiO
KW - Reduced graphene oxide
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U2 - 10.1016/j.electacta.2019.134968
DO - 10.1016/j.electacta.2019.134968
M3 - Article
AN - SCOPUS:85072867445
VL - 326
JO - Electrochimica Acta
JF - Electrochimica Acta
SN - 0013-4686
M1 - 134968
ER -