Abstract Reduced graphene oxide nanosheets modified with rich carbonyl groups (C=O) was obtained through a facile dehydration process by making use of the synergistic effect between phosphoric acid and monosodium phosphate. The product exhibited a high specific capacitance of 413 F g−1 at the current density of 0.25 A g−1 mainly owing to the high percentage of retained C=O groups which provided reversible pseudocapacitance and favored good dispersion. Additionally, the symmetric supercapacitors based on the modified graphene nanosheets showed high specific capacitance (314.2 F g−1 at 1 A g−1) and superior electrochemical stability with only 5.8% loss of its initial specific capacitance after 10000 cycle tests (at the current densities of 5 A g−1). The present work proposed an environmentally friendly way in controlling surface structure of reduced graphene oxide which promises great potential of graphene-based electrode materials for high performance energy-storage devices.

中文翻译：

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一种用残留羰基还原氧化石墨烯以提高电化学性能的绿色方法

摘要 利用磷酸和磷酸一钠的协同作用，通过简单的脱水过程获得了富羰基（C=O）修饰的还原氧化石墨烯纳米片。该产品在 0.25 A g-1 的电流密度下表现出 413 F g-1 的高比电容，这主要是由于高百分比的保留 C=O 基团提供了可逆的赝电容并有利于良好的分散。此外，基于改性石墨烯纳米片的对称超级电容器显示出高比电容（1 A g-1 时为 314.2 F g-1）和优异的电化学稳定性，10000 次循环测试后（在电流下）其初始比电容仅损失 5.8%。 5 A g-1 的密度）。