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Selected Works

Shi Xue Dou

2014

Graphene

Articles 1 - 5 of 5

Full-Text Articles in Physical Sciences and Mathematics

High-Performance Sodium-Ion Batteries And Sodium-Ion Pseudocapacitors Based On Mos2/Graphene Composites, Yunxiao Wang, Shulei Chou, David Wexler, Hua-Kun Liu, S X. Dou Oct 2014

High-Performance Sodium-Ion Batteries And Sodium-Ion Pseudocapacitors Based On Mos2/Graphene Composites, Yunxiao Wang, Shulei Chou, David Wexler, Hua-Kun Liu, S X. Dou

Shi Xue Dou

Sodium-ion energy storage, including sodium-ion batteries (NIBs) and electrochemical capacitive storage (NICs), is considered as a promising alternative to lithium-ion energy storage. It is an intriguing prospect, especially for large-scale applications, owing to its low cost and abundance. MoS2 sodiation/desodiation with Na ions is based on the conversion reaction, which is not only able to deliver higher capacity than the intercalation reaction, but can also be applied in capacitive storage owing to its typically sloping charge/discharge curves. Here, NIBs and NICs based on a graphene composite (MoS2/G) were constructed. The enlarged d-spacing, a contribution of the graphene matrix, and the …


Reduced Graphene Oxide With Superior Cycling Stability And Rate Capability For Sodium Storage, Yunxiao Wang, Shulei Chou, Hua-Kun Liu, S X. Dou Mar 2014

Reduced Graphene Oxide With Superior Cycling Stability And Rate Capability For Sodium Storage, Yunxiao Wang, Shulei Chou, Hua-Kun Liu, S X. Dou

Shi Xue Dou

Sodium ion battery is a promising electrical energy storage system for sustainable energy storage applications due to the abundance of sodium resources and their low cost. In this communication, the electrochemical properties of sodium ion storage in reduced graphene oxide (RGO) were studied in an electrolyte consisting of 1 M NaClO4 in propylene carbonate (PC). The experimental results show that the RGO anode allowed significant sodium ion insertion, leading to higher capacity at high current density compared to the previously reported results for carbon materials. This is due to the fact that RGO possesses higher electrical conductivity and is a …


A Facile Route To Synthesize Transition Metal Oxide/Reduced Graphene Oxide Composites And Their Lithium Storage Performance, Chongjun Zhao, Shulei Chou, Yunxiao Wang, Cuifeng Zhou, Hua-Kun Liu, S X. Dou Mar 2014

A Facile Route To Synthesize Transition Metal Oxide/Reduced Graphene Oxide Composites And Their Lithium Storage Performance, Chongjun Zhao, Shulei Chou, Yunxiao Wang, Cuifeng Zhou, Hua-Kun Liu, S X. Dou

Shi Xue Dou

Transition metal oxide (Mn3O4, Fe2O3, Co3O4, and ZnO) and reduced graphene oxide (RGO) composites were successfully synthesized via a hydrothermal method using the direct reaction between the corresponding metal powder and graphene oxide (GO). In this process, the GO can be reduced by transition metal powder in water, and the nanosized metal oxide can be obtained, and homogeneously mixed with and wrapped by RGO to form a metal oxide/RGO composite at the same time. X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, and scanning and transmission electron microscopy were used to characterize the as-prepared materials. The different experimental parameters, including reactants, …


Fusion Of Nacre, Mussel, And Lotus Leaf: Bio-Inspired Graphene Composite Paper With Multifunctional Integration, Da Zhong, Qinglin Yang, Lin Guo, S X. Dou, Kesong Liu, Lei Jiang Mar 2014

Fusion Of Nacre, Mussel, And Lotus Leaf: Bio-Inspired Graphene Composite Paper With Multifunctional Integration, Da Zhong, Qinglin Yang, Lin Guo, S X. Dou, Kesong Liu, Lei Jiang

Shi Xue Dou

Multifunctional integration is an inherent characteristic for biological materials with multiscale structures. Learning from nature is an effective approach for scientists and engineers to construct multifunctional materials. In nature, mollusks (abalone), mussels, and the lotus have evolved different and optimized solutions to survive. Here, bio-inspired multifunctional graphene composite paper was fabricated in situ through the fusion of the different biological solutions from nacre (brick-and-mortar structure), mussel adhesive protein (adhesive property and reducing character), and the lotus leaf (self-cleaning effect). Owing to the special properties (self-polymerization, reduction, and adhesion), dopamine could be simultaneously used as a reducing agent for graphene oxide …


The Electrochemical Properties Of High-Capacity Sulfur/Reduced Graphene Oxide With Different Electrolyte Systems, Yunxiao Wang, Shulei Chou, Hua-Kun Liu, S X. Dou Mar 2014

The Electrochemical Properties Of High-Capacity Sulfur/Reduced Graphene Oxide With Different Electrolyte Systems, Yunxiao Wang, Shulei Chou, Hua-Kun Liu, S X. Dou

Shi Xue Dou

The lithium/sulfur battery is a promising electrochemical system with high capacity, which is well-known to undergo a complex multistep reaction during the discharge process. Two types of electrolytes including poly (ethylene glycol) dimethyl ether (PEGDME)-based and 1.3 - dioxolane (DOL)/ dimethoxyethane (DME)-based electrolytes were investigated here. Furthermore, LiNO3 additive was introduced into the electrolyte in order to effectively eliminate the overcharge effect. The lithium sulfur battery with 1.0 M LiN(CF3SO2)2 in PEGME with 0.1 M LiNo3 shows highly stable reversible capacity of 624.8 mAh g-1 after 200 cycles and improved average coulombic efficiency of 98 percent.