High‐Conductive Protonated Layered Oxides from H2O Vapor‐Annealed Brownmillerites. Issue 48 (29th September 2021)

• Record Type: Journal Article
• Authors: Hu, Songbai; Zhu, Yuanmin; Han, Wenqiao; Li, Xiaowen; Ji, Yanjiang; Ye, Mao; Jin, Cai; Liu, Qi; Hu, Sixia; Wang, Jiaou; Wang, Junling; He, Jiaqing; Cazorla, Claudio; Chen, Lang
• Is Part Of: Advanced materials. Volume 33:Issue 48(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-09-29
• Subjects: brownmillerite -- conductivity -- layered oxides -- protons -- water vapor; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adma.202104623
• Languages: English
• ISSNs: 0935-9648

Abstract

Abstract: Protonated 3d transition‐metal oxides often display low electronic conduction, which hampers their application in electric, magnetic, thermoelectric, and catalytic fields. Electronic conduction can be enhanced by co‐inserting oxygen acceptors simultaneously. However, the currently used redox approaches hinder protons and oxygen ions co‐insertion due to the selective switching issues. Here, a thermal hydration strategy for systematically exploring the synthesis of conductive protonated oxides from 3d transition‐metal oxides is introduced. This strategy is illustrated by synthesizing a novel layered‐oxide SrCoO3 H from the brownmillerite SrCoO2.5 . Compared to the insulating SrCoO2.5, SrCoO3 H exhibits an unprecedented high electronic conductivity above room temperature, water uptake at 250 °C, and a thermoelectric power factor of up to 1.2 mW K −2 m −1 at 300 K. These findings open up opportunities for creating high‐conductive protonated layered oxides by protons and oxygen ions co‐doping. Abstract : Protonated 3d transition‐metal oxides often display low electronic conduction, which hampers their application in electric, magnetic, thermoelectric, and catalytic fields. In this work, a thermal hydration synthesis of conductive protonated oxides from 3d transition‐metal oxides is introduced. By incorporating H2 O into the lattice frame, the insulating brownmillerite SrCoO2.5 transforms to a novel layered‐oxide SrCoO3 H, which demonstrates a highly improved electric conduction.