AUTHOR=Zhou Qu , Lu Zhaorui , Wei Zhijie , Xu Lingna , Gui Yingang , Chen Weigen TITLE=Hydrothermal Synthesis of Hierarchical Ultrathin NiO Nanoflakes for High-Performance CH4 Sensing JOURNAL=Frontiers in Chemistry VOLUME=6 YEAR=2018 URL=https://www.frontiersin.org/journals/chemistry/articles/10.3389/fchem.2018.00194 DOI=10.3389/fchem.2018.00194 ISSN=2296-2646