Sustainable methanol production via CO_(2) hydrogenation leads to increased interest in the understanding of active phase of Cu/ZnO/Al_(2)O_(3)(CZA) catalyst. Model catalysts of ZnO/Cu(111) with structures varied from...Sustainable methanol production via CO_(2) hydrogenation leads to increased interest in the understanding of active phase of Cu/ZnO/Al_(2)O_(3)(CZA) catalyst. Model catalysts of ZnO/Cu(111) with structures varied from two-dimensional planar to three-dimensional nanoparticles were prepared by atomic layer deposition(ALD) method. By combing scanning tunneling microscopy(STM) and X-ray photoelectron spectroscopy(XPS) at near-ambient pressure of CO_(2) hydrogenation, we reveal that the submonolayer ZnO/Cu(111) transformed into Cu-Zn alloy under 10 mbar CO_(2)/H_(2) at 493 K, and underwent a partial reoxidation during evacuation. The dynamic phase transformation of ZnO/Cu(111) may partly explain the existence of differences and apparently contradictory theories to account for the origin of active phase in CZA catalysts.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 the National Natural Science Foundation of China (No. 91845109, No. 21872169)。
文摘Sustainable methanol production via CO_(2) hydrogenation leads to increased interest in the understanding of active phase of Cu/ZnO/Al_(2)O_(3)(CZA) catalyst. Model catalysts of ZnO/Cu(111) with structures varied from two-dimensional planar to three-dimensional nanoparticles were prepared by atomic layer deposition(ALD) method. By combing scanning tunneling microscopy(STM) and X-ray photoelectron spectroscopy(XPS) at near-ambient pressure of CO_(2) hydrogenation, we reveal that the submonolayer ZnO/Cu(111) transformed into Cu-Zn alloy under 10 mbar CO_(2)/H_(2) at 493 K, and underwent a partial reoxidation during evacuation. The dynamic phase transformation of ZnO/Cu(111) may partly explain the existence of differences and apparently contradictory theories to account for the origin of active phase in CZA catalysts.
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.
