1. O22-/O- functionalized oxygen-deficient Co3O4 nanorods as high performance supercapacitor electrodes and electrocatalysts towards water splitting.
- Author
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Cheng, Guanhua, Kou, Tianyi, Zhang, Jie, Si, Conghui, Gao, Hui, and Zhang, Zhonghua
- Abstract
Owing to high theoretical specific capacitance of 3560 F g −1 and intrinsic activity towards oxygen evolution reaction (OER), inexpensive Co 3 O 4 is drawing much attention as either a promising pseudocapacitive electrode or OER catalyst. However, restricted to poor conductivity and lack of active sites, Co 3 O 4 usually exhibits limited experimental capacitance and OER activity, barely satisfying high energy density delivering of supercapacitors and low energy input of water-splitting systems. Herein, we report O 2 2- /O - functionalized oxygen-deficient Co 3 O 4 nanorods for supercapacitor and water splitting dual applications. The CoC 2 O 4 ·2H 2 O converted oxygen-deficient Co 3 O 4 nanorods show enhanced electrical conductivity as confirmed by the increased carrier density. The increased number of Co 2+ sites (oxygen vacancies) and CoOOH are believed to contribute to the improvement in faradaic reactions and OER activity. Additionally, surface functionalization by O 2 2- /O - is realized in oxygen-deficient Co 3 O 4 nanorods. On the basis of these merits, the as-synthesized Co 3 O 4 nanorods demonstrate a significantly high specific capacitance of 739 F g −1 and an ultralow overpotential of 275 mV at 10 mA cm −2 for OER with ultralong stability of over 300 h (@ 100 mA cm −2 ). Specifically, an electrolyzer for overall water splitting can be driven by asymmetric supercapacitors with the optimized cobalt oxide as both electrocatalyst and electrode material. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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