Electrocatalytic nitrogen reduction reaction(NRR)is regarded as a potential routine to achieve environment-friendly ammonia production,because of its abundant nitrogen resources,clean energy utilization and flexible o...Electrocatalytic nitrogen reduction reaction(NRR)is regarded as a potential routine to achieve environment-friendly ammonia production,because of its abundant nitrogen resources,clean energy utilization and flexible operation.However,it is hindered by low activity and selectivity,in which con-dition well-designed catalysts are urgently in need.In this work,a binary Mo/Ir nanodots/carbon(Mo/Ir/C)hetero-material is efficiently constructed via microfluidic strategy,of which the nanodots are ho-mogeneously distributed on the carbon skeleton and the average size is approximately 1 nm.Excellent performance for NRR is obtained in 1 mol L^(-1) KOH,of which the optimized ammonia yield and faradic efficiency are 7.27μg h^(-1) cm^(-2) and 2.31%respectively.Moreover,the optimized ammonia yield of 6.20μg h-1 cm-2 and faradic efficiency of 10.59%are also obtained in 0.005 mol L^(-1) H_(2)SO_(4).This work achieves the continuous-flow synthesis and controllable adjustment of hetero-materials for favorable morphologies,which provides an innovative pathway for catalyst design and further promotes the development of ammonia production field.展开更多
Recently, owing to high costs and increasing demands for better catalysts, it is worthwhile to improve its activity and selectivity, and reduce its costs. Adding secondary promoters such as phosphorus, boron, magnesiu...Recently, owing to high costs and increasing demands for better catalysts, it is worthwhile to improve its activity and selectivity, and reduce its costs. Adding secondary promoters such as phosphorus, boron, magnesium, titanium, zinc and ruthenium to Co-Mo/Al;O;catalyst has been proved to be one of the ways to attain this result. The addition of those metals or metal oxides changes the surface states of molybdenumstructure.展开更多
A series of Mo-impregnated H\%β\% samples, with MoO\-3 loading in H\%β\% zeolite in the mass fraction range of 0\^5%\_6\^0%, were studied by means of XRD and IR in order to characterize their structures. Mo/H\%β\% ...A series of Mo-impregnated H\%β\% samples, with MoO\-3 loading in H\%β\% zeolite in the mass fraction range of 0\^5%\_6\^0%, were studied by means of XRD and IR in order to characterize their structures. Mo/H\%β\% samples′ crystallinity almost linearly decreases with increasing the amount of MoO\-3 loaded. The IR spectra and XRD patterns suggest that the progressive destabilization of the H\%β\% zeolite structure is caused by increasing Mo loading in (MoO\-3+H\%β\% zeolite). During the calcination, Al\-2(MoO\-4)\-3 formed from the dealumination of H\%β\% zeolite, causes the substantially partial breakdown of the zeolite framework when the Mo loading in MoO\-3+H\%β\% is relatively high.展开更多
The molecular geometries and electronic structures of two isomers of benzotrifuroxan (BTF) have been studied using ab initio molecular orbital method at the HF/6 31G * level. The calculated results show that the...The molecular geometries and electronic structures of two isomers of benzotrifuroxan (BTF) have been studied using ab initio molecular orbital method at the HF/6 31G * level. The calculated results show that the hexanitroso isomer has much higher energy than the tetracyclic form and is unstable. Infrared frequencies have been calculated for the stable tetracyclic structure and scaled by 0.89. The scaled frequencies agree well with the available experimental results, and have been used to derive the standard thermodynamic functions, heat capacity( Cp °), entropy( S °) and enthalpy( H° H 298 °).展开更多
[(η5-C5H4Me)Mo(CO)2PPh3I] undergoes solid state transformation on the formation of a good pellet for FT IR measurement. There was a formation of the products mixture on pelleting using different diluents of group I m...[(η5-C5H4Me)Mo(CO)2PPh3I] undergoes solid state transformation on the formation of a good pellet for FT IR measurement. There was a formation of the products mixture on pelleting using different diluents of group I metal salts on either the cis or the trans isomer of the [(η5-C5H4Me)Mo(CO)2PPh3I] complex. The cis or the trans isomer gave the same IR spectra i.e. a mixture of cis and trans isomer of the complex. It does not matter the isomer started with in the course of solid state transformation reaction, an equilibrium ratio of 30/70 (trans/cis) will still be achieved. The solid state IR spectra show very strong peaks at νco 1957, 1947 and strong peaks at 1867, 1853 cm–1. The individual IR cis/trans isomer will therefore show at 1947 and 1853/1957 and 1867 cm–1. The solution IR spectra gave, cis = 1961, 1875 and trans = 1963, 1882 cm–1 in dry CHCl3. Hence, most of the solid state IR measurement of the organometallic complex of the type (η5-C5H4Me)Mo(CO)2(PPh3)I on pelleting will give isomer mixture.展开更多
基金supported by the National Natural Science Foundation of China(grant Nos.22025801 and 22208190)National Postdoctoral Program for Innovative Talents(grant No.BX2021146)Shuimu Tsinghua Scholar Program(grant No.2021SM055).
文摘Electrocatalytic nitrogen reduction reaction(NRR)is regarded as a potential routine to achieve environment-friendly ammonia production,because of its abundant nitrogen resources,clean energy utilization and flexible operation.However,it is hindered by low activity and selectivity,in which con-dition well-designed catalysts are urgently in need.In this work,a binary Mo/Ir nanodots/carbon(Mo/Ir/C)hetero-material is efficiently constructed via microfluidic strategy,of which the nanodots are ho-mogeneously distributed on the carbon skeleton and the average size is approximately 1 nm.Excellent performance for NRR is obtained in 1 mol L^(-1) KOH,of which the optimized ammonia yield and faradic efficiency are 7.27μg h^(-1) cm^(-2) and 2.31%respectively.Moreover,the optimized ammonia yield of 6.20μg h-1 cm-2 and faradic efficiency of 10.59%are also obtained in 0.005 mol L^(-1) H_(2)SO_(4).This work achieves the continuous-flow synthesis and controllable adjustment of hetero-materials for favorable morphologies,which provides an innovative pathway for catalyst design and further promotes the development of ammonia production field.
文摘Recently, owing to high costs and increasing demands for better catalysts, it is worthwhile to improve its activity and selectivity, and reduce its costs. Adding secondary promoters such as phosphorus, boron, magnesium, titanium, zinc and ruthenium to Co-Mo/Al;O;catalyst has been proved to be one of the ways to attain this result. The addition of those metals or metal oxides changes the surface states of molybdenumstructure.
基金Supported by the National Natural Science Foundation of China(No.2 0 30 30 19) and the National"973"Project of China(No.2 0 0 3CB6 15 80 2 )
文摘A series of Mo-impregnated H\%β\% samples, with MoO\-3 loading in H\%β\% zeolite in the mass fraction range of 0\^5%\_6\^0%, were studied by means of XRD and IR in order to characterize their structures. Mo/H\%β\% samples′ crystallinity almost linearly decreases with increasing the amount of MoO\-3 loaded. The IR spectra and XRD patterns suggest that the progressive destabilization of the H\%β\% zeolite structure is caused by increasing Mo loading in (MoO\-3+H\%β\% zeolite). During the calcination, Al\-2(MoO\-4)\-3 formed from the dealumination of H\%β\% zeolite, causes the substantially partial breakdown of the zeolite framework when the Mo loading in MoO\-3+H\%β\% is relatively high.
文摘The molecular geometries and electronic structures of two isomers of benzotrifuroxan (BTF) have been studied using ab initio molecular orbital method at the HF/6 31G * level. The calculated results show that the hexanitroso isomer has much higher energy than the tetracyclic form and is unstable. Infrared frequencies have been calculated for the stable tetracyclic structure and scaled by 0.89. The scaled frequencies agree well with the available experimental results, and have been used to derive the standard thermodynamic functions, heat capacity( Cp °), entropy( S °) and enthalpy( H° H 298 °).
文摘[(η5-C5H4Me)Mo(CO)2PPh3I] undergoes solid state transformation on the formation of a good pellet for FT IR measurement. There was a formation of the products mixture on pelleting using different diluents of group I metal salts on either the cis or the trans isomer of the [(η5-C5H4Me)Mo(CO)2PPh3I] complex. The cis or the trans isomer gave the same IR spectra i.e. a mixture of cis and trans isomer of the complex. It does not matter the isomer started with in the course of solid state transformation reaction, an equilibrium ratio of 30/70 (trans/cis) will still be achieved. The solid state IR spectra show very strong peaks at νco 1957, 1947 and strong peaks at 1867, 1853 cm–1. The individual IR cis/trans isomer will therefore show at 1947 and 1853/1957 and 1867 cm–1. The solution IR spectra gave, cis = 1961, 1875 and trans = 1963, 1882 cm–1 in dry CHCl3. Hence, most of the solid state IR measurement of the organometallic complex of the type (η5-C5H4Me)Mo(CO)2(PPh3)I on pelleting will give isomer mixture.
