Because of the intriguing electronic properties, high specific surface areas and confinement effect, two-dimensional(2D) noble metal nanosheets usually exhibit fascinating physicochemical properties and thus hold grea...Because of the intriguing electronic properties, high specific surface areas and confinement effect, two-dimensional(2D) noble metal nanosheets usually exhibit fascinating physicochemical properties and thus hold great promises in fuel cell devices and beyond. Herein, 2D porous Pt nanosheets composed by interweaved ultrathin nanowires are successfully fabricated via a facile NaCl-templated process. Controlled experiments demonstrate that the adoption of NaCl and appropriate ratio of NaCl and Pt precursor are indispensable for the formation of porous Pt nanosheets. Impressively, the cost-effective NaCl template can be recyclable through a simple recrystallization procedure, which may greatly reduce the synthetic cost. By virtue of their structural merits, including high porosity, 2D anisotropy and abundant defects, the resultant porous Pt nanosheets exhibit superior activity and enhanced stability towards the oxygen reduction reaction(ORR) compared to the commercial Pt black in alkaline medium. The present study not only offers a high-performance electrocatalyst for fuel cell devices, but also provides a new perspective toward the rational synthesis of 2D noble metal nanosheets with high porosity and diverse functionalities.展开更多
Two-dimensional(2D)indium arsenide(InAs)is promising for future electronic and optoelectronic applications such as highperformance nanoscale transistors,flexible and wearable devices,and high-sensitivity broadband pho...Two-dimensional(2D)indium arsenide(InAs)is promising for future electronic and optoelectronic applications such as highperformance nanoscale transistors,flexible and wearable devices,and high-sensitivity broadband photodetectors,and is advantageous for its heterogeneous integration with Si-based electronics.However,the synthesis of 2D InAs single crystals is challenging because of the nonlayered structure.Here we report the van der Waals epitaxy of 2D InAs single crystals,with their thickness down to 4.8 nm,and their lateral sizes up to~37μm.The as-grown InAs flakes have high crystalline quality and are homogenous.The thickness can be tuned by growth time and temperature.Moreover,we explore the thickness-dependent optical properties of InAs flakes.Transports measurement reveals that 2D InAs possesses high conductivity and high carrier mobility.Our work introduces InAs to 2D materials family and paves the way for applying 2D InAs in high-performance electronics and optoelectronics.展开更多
基金financially supported by National Natural Science Foundation of China (21503111 and 21576139)Natural Science Foundation of Jiangsu Province (BK20171473)+3 种基金Jiangsu Science and Technology support project (BE2014859) Natural Science Foundation of Jiangsu Higher Education Institutions of China (16KJB150020)supports from National and Local Joint Engineering Research Center of Biomedical Functional Materialsa project sponsored by the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘Because of the intriguing electronic properties, high specific surface areas and confinement effect, two-dimensional(2D) noble metal nanosheets usually exhibit fascinating physicochemical properties and thus hold great promises in fuel cell devices and beyond. Herein, 2D porous Pt nanosheets composed by interweaved ultrathin nanowires are successfully fabricated via a facile NaCl-templated process. Controlled experiments demonstrate that the adoption of NaCl and appropriate ratio of NaCl and Pt precursor are indispensable for the formation of porous Pt nanosheets. Impressively, the cost-effective NaCl template can be recyclable through a simple recrystallization procedure, which may greatly reduce the synthetic cost. By virtue of their structural merits, including high porosity, 2D anisotropy and abundant defects, the resultant porous Pt nanosheets exhibit superior activity and enhanced stability towards the oxygen reduction reaction(ORR) compared to the commercial Pt black in alkaline medium. The present study not only offers a high-performance electrocatalyst for fuel cell devices, but also provides a new perspective toward the rational synthesis of 2D noble metal nanosheets with high porosity and diverse functionalities.
基金supported by the National Key Basic Research Program of China(No.2021YFA1401400)the start-up funds of Shanghai Jiao Tong University,the National Natural Science Foundation of China(Nos.52103344,52031014,22022507,and 51973111)+1 种基金the National Key Research and Development Program of China(No.2017YFA0206301)Beijing National Laboratory for Molecular Sciences(No.BNLMS202004).
文摘Two-dimensional(2D)indium arsenide(InAs)is promising for future electronic and optoelectronic applications such as highperformance nanoscale transistors,flexible and wearable devices,and high-sensitivity broadband photodetectors,and is advantageous for its heterogeneous integration with Si-based electronics.However,the synthesis of 2D InAs single crystals is challenging because of the nonlayered structure.Here we report the van der Waals epitaxy of 2D InAs single crystals,with their thickness down to 4.8 nm,and their lateral sizes up to~37μm.The as-grown InAs flakes have high crystalline quality and are homogenous.The thickness can be tuned by growth time and temperature.Moreover,we explore the thickness-dependent optical properties of InAs flakes.Transports measurement reveals that 2D InAs possesses high conductivity and high carrier mobility.Our work introduces InAs to 2D materials family and paves the way for applying 2D InAs in high-performance electronics and optoelectronics.
