2D Electron Gas and Oxygen Vacancy Induced High Oxygen Evolution Performances for Advanced Co3O4/CeO2 Nanohybrids
Liu, Y (Liu, Ying)[ 1 ] ; Ma, C (Ma, Chao)[ 2 ] ; Zhang, QH (Zhang, Qinghua)[ 3 ] ; Wang, W (Wang, Wei)[ 1 ] ; Pan, PF (Pan, Pengfei)[ 4 ] ; Gu, L (Gu, Lin)[ 3 ] ; Xu, DD (Xu, Dongdong)[ 1 ] ; Bao, JC (Bao, Jianchun)[ 1 ]*（包建春）; Dai, ZH (Dai, Zhihui)[ 1 ]*（戴志晖）
[ 1 ] Nanjing Normal Univ, Sch Chem & Mat Sci, Jiangsu Collaborat Innovat Ctr Biomed Funct Mat, Nanjing 210023, Jiangsu, Peoples R China
[ 2 ] Shandong Agr Univ, Coll Informat Sci & Engn, Tai An 271000, Shandong, Peoples R China
[ 3 ] Chinese Acad Sci, Inst Phys, Beijing Natl Lab Condensed Matter Phys, Beijing 100190, Peoples R China
[ 4 ] Nanjing Normal Univ, Sch Phys & Technol, Nanjing 210023, Jiangsu, Peoples R China
The rational design of atomic-scale interfaces in multiphase nanohybrids is an alluring and challenging approach to develop advanced electrocatalysts. Herein, through the selection of two different metal oxides with particular intrinsic features, advanced Co3O4/CeO2 nanohybrids (NHs) with CeO2 nanocubes anchored on Co3O4 nanosheets are developed, which show not only high oxygen vacancy concentration but also remarkable 2D electron gas (2DEG) behavior with approximate to 0.79 +/- 0.1 excess e(-)/u.c. on the Ce3+ sites at the Co3O4-CeO2 interface. Such a 2DEG transport channel leads to a high carrier density of 3.8 x 10(14) cm(-2) and good conductivity. Consequently, the Co3O4/CeO2 NHs demonstrate dramatically enhanced oxygen evolution reaction (OER) performances with a low overpotential of 270 mV at 10 mA cm(-2) and a high turnover frequency of 0.25 s(-1) when compared to those of pure Co3O4 and CeO2 counterparts, outperforming commercial IrO2 and some recently reported representative OER catalysts. These results demonstrate the validity of tailoring the electrocatalytic properties of metal oxides by 2DEG engineering, offering a step forward in the design of advanced hybrid nanostructures.