The nitrate reduction reaction(NtRR)has been demonstrated to be a promising way for obtaining ammonia(NH_(3))by converting NO3-to NH3.Here we report the controlled synthesis of cobalt tetroxide/graphdiyne heterostruct...The nitrate reduction reaction(NtRR)has been demonstrated to be a promising way for obtaining ammonia(NH_(3))by converting NO3-to NH3.Here we report the controlled synthesis of cobalt tetroxide/graphdiyne heterostructured nanowires(Co_(3)O_(4)/GDY NWs)by a simple two-step process including the synthesis of Co_(3)O_(4)NWs and the following growth of GDY using hex-aethynylbenzene as the precursor at 110°C for 10 h.Detailed scanning electron microscopy,high resolution transmission electron microscopy,X-ray photoelectron spectroscopy,and Raman characterization confirmed the synthesis of a Co_(3)O_(4)/GDY heterointerface with the formation of sp-C-Co bonds at the interface and incomplete charge transfer between GDY and Co,which provide a con-tinuous supply of electrons for the catalytic reaction and ensure a rapid NtRR.Because of these advantages,Co_(3)O_(4)/GDY NWs had an excellent NtRR performance with a high NH3 yield rate(YNH3)of 0.78 mmol h^(-1)cm^(-2)and a Faraday efficiency(FE)of 92.45%at-1.05 V(vs.RHE).This work provides a general approach for synthesizing heterostructures that can drive high-performance ammo-nia production from wastewater under ambient conditions.展开更多
A series of spinel Li-Mn-Ni composite oxides with theoretical chemical formula of LiNixMn2-xO4 （0〈_x〈_1.0） were synthesized by liquid phase method. Their structure and morphology were characterized by X-ray diffra...A series of spinel Li-Mn-Ni composite oxides with theoretical chemical formula of LiNixMn2-xO4 （0〈_x〈_1.0） were synthesized by liquid phase method. Their structure and morphology were characterized by X-ray diffractometry （XRD） and scanning electron microscopy （SEM）, respectively. The stability of these Ni-substituted spinel oxides prepared at different temperatures was investigated in acidic medium as well. The results show that Ni can be brought into the spinel framework completely to form well-crystallized product when x〈_0.5 and the optimized synthesis temperature is 800℃. LiNi0.4Mn1.6O4 prepared at 800℃ can maintain the spinel structure and morphology with Li extraction ratio of 30.37%, Mn extraction ratio of 8.78% and Ni extraction ratio of 1,82% during acid treatment. The incorporated Ni not only inhibits the dissolution of Mn, but also reduces the extraction of Li due to the lattice contraction展开更多
文摘The nitrate reduction reaction(NtRR)has been demonstrated to be a promising way for obtaining ammonia(NH_(3))by converting NO3-to NH3.Here we report the controlled synthesis of cobalt tetroxide/graphdiyne heterostructured nanowires(Co_(3)O_(4)/GDY NWs)by a simple two-step process including the synthesis of Co_(3)O_(4)NWs and the following growth of GDY using hex-aethynylbenzene as the precursor at 110°C for 10 h.Detailed scanning electron microscopy,high resolution transmission electron microscopy,X-ray photoelectron spectroscopy,and Raman characterization confirmed the synthesis of a Co_(3)O_(4)/GDY heterointerface with the formation of sp-C-Co bonds at the interface and incomplete charge transfer between GDY and Co,which provide a con-tinuous supply of electrons for the catalytic reaction and ensure a rapid NtRR.Because of these advantages,Co_(3)O_(4)/GDY NWs had an excellent NtRR performance with a high NH3 yield rate(YNH3)of 0.78 mmol h^(-1)cm^(-2)and a Faraday efficiency(FE)of 92.45%at-1.05 V(vs.RHE).This work provides a general approach for synthesizing heterostructures that can drive high-performance ammo-nia production from wastewater under ambient conditions.
基金Project(2008BAB35B04) supported by the National Key Technology R&D Program of ChinaProject(CX2010B111) supported by the Innovation Program of Doctoral Research of Hunan Province, ChinaProject(2010QZZD003) supported by Advanced Research Program of Central South University, China
文摘A series of spinel Li-Mn-Ni composite oxides with theoretical chemical formula of LiNixMn2-xO4 （0〈_x〈_1.0） were synthesized by liquid phase method. Their structure and morphology were characterized by X-ray diffractometry （XRD） and scanning electron microscopy （SEM）, respectively. The stability of these Ni-substituted spinel oxides prepared at different temperatures was investigated in acidic medium as well. The results show that Ni can be brought into the spinel framework completely to form well-crystallized product when x〈_0.5 and the optimized synthesis temperature is 800℃. LiNi0.4Mn1.6O4 prepared at 800℃ can maintain the spinel structure and morphology with Li extraction ratio of 30.37%, Mn extraction ratio of 8.78% and Ni extraction ratio of 1,82% during acid treatment. The incorporated Ni not only inhibits the dissolution of Mn, but also reduces the extraction of Li due to the lattice contraction
