TY - JOUR
T1 - Single atomic Ag enhances the bifunctional activity and cycling stability of MnO2
AU - Ni, Shenglin
AU - Zhang, Haojie
AU - Zhao, Yonghui
AU - Li, Xiaopeng
AU - Sun, Yu
AU - Qian, Jin
AU - Xu, Qing
AU - Gao, Peng
AU - Wu, Dekun
AU - Kato, Kenichi
AU - Yamauchi, Miho
AU - Sun, Yuhan
N1 - Funding Information:
S. Ni and H. Zhang contributed equally to the work. The synchrotron radiation experiments were performed at BL44B2 in SPring-8 with the approval of RIKEN. This work was supported by the Ministry of Science and Technology of China (2016YFA0202802) and National Science Foundation of China ( 21403280 ).
Publisher Copyright:
© 2019 Elsevier B.V.
PY - 2019/6/15
Y1 - 2019/6/15
N2 - Heterogeneous electrocatalyst with single atom feature has attracted great interests. Although significant progress has been made on constructing and understanding carbon supported single atom electrocatalysts (SAECs), few attentions has been paid to metal oxide supported SAECs. The effect of single atom in enhancing electrocatalytic activity and stability of metal oxides has been poorly understood. Here, we reported MnO2 nanowires loaded with single atomic Ag (Ag-MnO2) that can simultaneously catalyze oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). The incorporation of Ag into the crystal framework of α-MnO2 provided multiple benefits including an improved conductivity and a substantial increase in both lattice distortion and oxygen vacancies. As a result, Ag-MnO2 outperformed α-MnO2 in oxygen electrocatalysis and showed ∼3-fold enhancement in kinetic current density. The Zinc air battery containing the Ag-MnO2 displayed a high discharge peak power of 273.2 mW cm−2, an energy density of 915.4 Wh kgZn−1 and an outstanding rate performance. The Zinc air battery (ZAB) stably operated up to 3200 cycles of charge-discharge. Such excellent rechargeability can be ascribed to the promoted crystal phase transformation from α-MnO2 to δ-MnO2 that is beneficial for OER due to the presence of atomic Ag.
AB - Heterogeneous electrocatalyst with single atom feature has attracted great interests. Although significant progress has been made on constructing and understanding carbon supported single atom electrocatalysts (SAECs), few attentions has been paid to metal oxide supported SAECs. The effect of single atom in enhancing electrocatalytic activity and stability of metal oxides has been poorly understood. Here, we reported MnO2 nanowires loaded with single atomic Ag (Ag-MnO2) that can simultaneously catalyze oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). The incorporation of Ag into the crystal framework of α-MnO2 provided multiple benefits including an improved conductivity and a substantial increase in both lattice distortion and oxygen vacancies. As a result, Ag-MnO2 outperformed α-MnO2 in oxygen electrocatalysis and showed ∼3-fold enhancement in kinetic current density. The Zinc air battery containing the Ag-MnO2 displayed a high discharge peak power of 273.2 mW cm−2, an energy density of 915.4 Wh kgZn−1 and an outstanding rate performance. The Zinc air battery (ZAB) stably operated up to 3200 cycles of charge-discharge. Such excellent rechargeability can be ascribed to the promoted crystal phase transformation from α-MnO2 to δ-MnO2 that is beneficial for OER due to the presence of atomic Ag.
UR - http://www.scopus.com/inward/record.url?scp=85061793385&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85061793385&partnerID=8YFLogxK
U2 - 10.1016/j.cej.2019.02.084
DO - 10.1016/j.cej.2019.02.084
M3 - Article
AN - SCOPUS:85061793385
VL - 366
SP - 631
EP - 638
JO - Chemical Engineering Journal
JF - Chemical Engineering Journal
SN - 1385-8947
ER -