Phase and morphology evolution of ultrathin Co(OH)2 nanosheets towards supercapacitor application,CrystEngComm

当前位置： X-MOL 学术 › CrystEngComm › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Phase and morphology evolution of ultrathin Co(OH)2 nanosheets towards supercapacitor application
CrystEngComm ( IF 2.6 ) Pub Date : 2017-08-23 00:00:00 , DOI: 10.1039/c7ce01130j
Kun Ding _{1,

2,

3,

4} , Xiao Zhang _{5,

6,

7,

8} , Juping Li _{1,

2,

3,

4} , Ping Yang _{1,

2,

3,

4} , Xin Cheng _{1,

2,

3,

4}

Affiliation

Ultrathin α-Co(OH)₂ nanosheets (NSs) were hydrothermally synthesized without using surfactants and templates. Interestingly, the ultrathin α-Co(OH)₂ NSs evolved from graphene-like NSs to hexagonal nanoplates (NPs) and then transformed into a needle-like Co(CO₃)_0.5(OH)·0.11H₂O phase with increasing reaction temperature and time. The phase and morphology evolution depended strongly on the CO₃²⁻ ions in the solution. We ruled out the possibility that CO₃²⁻ originated from the adsorption of CO₂ in air and proposed the possible phase transition mechanism from α-Co(OH)₂ to Co(CO₃)_0.5(OH)·0.11H₂O, which was due to the decomposition of hexamethylenetetramine driven by dynamics and thermodynamics. The morphology evolution could be regarded as the dissolution–recrystallization–redissolution–recrystallization of α-Co(OH)₂. The electrochemical behavior tests demonstrated that the ultrathin α-Co(OH)₂ electrode exhibited an excellent specific capacitance of 833.4 F g⁻¹ at 5 A g⁻¹; however, the specific capacitance of the needle-like Co(CO₃)_0.5(OH)·0.11H₂O electrode was 247.2 F g⁻¹ at the same current density. This excellent electrochemical property is attributed to the crystalline phase and ultrathin nature of the materials.

中文翻译：

超薄Co（OH）₂纳米片向超级电容器应用的相和形态演变

无需使用表面活性剂和模板即可水热合成超薄α-Co（OH）₂纳米片（NSs）。有趣的是，超薄的α-Co（OH）₂ NSs从石墨烯状的NSs演化为六角形的纳米板（NPs），然后随着反应的增加而转变为针状的Co（CO ₃）_0.5（OH）·0.11H ₂ O相。温度和时间。相和形态的演变很大程度上取决于溶液中的CO ₃^2-离子。我们排除了CO ₃^2-源自空气中CO ₂吸附的可能性，并提出了从α-Co（OH）₂到Co（CO ）的可能相变机理。₃）_0.5（OH）·0.11H₂ O，这是由于动力学和热力学驱动的六亚甲基四胺的分解。形态演化可以看作是α-Co（OH）₂的溶解-重结晶-再溶解-重结晶。电化学行为测试表明，超薄α-的Co（OH）₂电极表现出833.4 F G优异的比电容^-1在5A克^-1 ; 但是，针状Co（CO₃）_0.5（OH）·0.11H₂ O电极的比电容为247.2 F g^-1在相同的电流密度下。这种优异的电化学性能归因于材料的结晶相和超薄特性。

更新日期：2017-09-20

点击分享查看原文

点击收藏

阅读更多本刊最新论文本刊介绍/投稿指南11