title: Ultrafine Nb2O5 Nanocrystal Coating on Reduced Graphene Oxide as Anode Material for High Performance Sodium Ion Battery.
abstract: Ultrafine niobium oxide nanocrystals/reduced graphene oxide (Nb2O5 NCs/rGO) was demonstrated as a promising anode material for sodium ion battery with high rate performance and high cycle durability. Nb2O5 NCs/rGO was synthesized by controllable hydrolysis of niobium ethoxide and followed by heat treatment at 450 °C in flowing forming gas. Transmission electron microscopy images showed that Nb2O5 NCs with average particle size of 3 nm were uniformly deposited on rGO sheets and voids among Nb2O5 NCs existed. The architecture of ultrafine Nb2O5 NCs anchored on a highly conductive rGO network can not only enhance charge transfer and buffer the volume change during sodiation/desodiation process but also provide more active surface area for sodium ion storage, resulting in superior rate and cycle performance. Ex situ XPS analysis revealed that the sodium ion storage mechanism in Nb2O5 could be accompanied by Nb(5+)/Nb(4+) redox reaction and the ultrafine Nb2O5 NCs provide more surface area to accomplish the redox reaction.
authors: Department of Chemical and Materials Engineering, New Mexico State University , New Mexico 88003, United States.
authors: Litao
authors: L
authors: Yan
authors: Department of Chemical and Materials Engineering, New Mexico State University , New Mexico 88003, United States.
authors: Gen
authors: G
authors: Chen
authors: Department of Chemical and Materials Engineering, New Mexico State University , New Mexico 88003, United States.
authors: Swagotom
authors: S
authors: Sarker
authors: Department of Chemical and Materials Engineering, New Mexico State University , New Mexico 88003, United States.
authors: Stephanie
authors: S
authors: Richins
authors: Department of Chemical and Materials Engineering, New Mexico State University , New Mexico 88003, United States.|College of Mechanical and Electrical Engineering, Agricultural University of Hebei , Baoding 071001, China.
authors: Huiqiang
authors: H
authors: Wang
authors: Department of Chemical and Materials Engineering, New Mexico State University , New Mexico 88003, United States.
authors: Weichuan
authors: W
authors: Xu
authors: School of Energy and Environment, Anhui University of Technology , Maanshan 243002, China.
authors: Xianhong
authors: X
authors: Rui
authors: Department of Chemical and Materials Engineering, New Mexico State University , New Mexico 88003, United States.
authors: Hongmei
authors: H
authors: Luo
keywords: Nb2O5; anode; graphene oxide; sodium ion battery; ultrafine