Ammonia has been recognized as a promising fuel for solid oxide fuel cells(SOFCs)because of its relatively high hydrogen content and high energy density.However,the effective catalysis of ammonia on the surface of sta...Ammonia has been recognized as a promising fuel for solid oxide fuel cells(SOFCs)because of its relatively high hydrogen content and high energy density.However,the effective catalysis of ammonia on the surface of state-of-the-art anode greatly hinders the further development of direct ammonia SOFCs.In this study,we report our findings of surface activating and stabilizing of a Ni-based cermet anode for highly efficient and durable operation on ammonia fuel,achieved by a surface coating of CeO_(2)−δnanoparticles(NPs).When incorporated into a Ni-yttria-stabilized zirconia(Ni-YSZ)anode-supported single cell,the coatings demonstrate an improved electrochemical reaction activity and stability,achieving a high peak power density of 0.941 W·cm^(−2)at 700℃,and a promising stability of~60 h(degradation rate of 0.127%h^(−1)at 0.5 A·cm−2),much better than those of cells with a bare anode(~0.673 W·cm^(−2)and degradation rate of 0.294%h−1 at 0.5 A·cm^(-2)).The catalytic NPs significantly enhance the reaction activity toward the decomposition of ammonia and oxidation of hydrogen,especially at low temperatures(<700℃),as confirmed by the detailed distribution of relaxation time(DRT)analyses of the impedance spectra of the cells on NH3 fuel.展开更多
Fuel flexibility is one of the most distinguished advantages of solid oxide fuel cells(SOFCs)over other low-temperature fuel cells.Furthermore,the combination of ammonia fuel and SOFCs technology should be a promising...Fuel flexibility is one of the most distinguished advantages of solid oxide fuel cells(SOFCs)over other low-temperature fuel cells.Furthermore,the combination of ammonia fuel and SOFCs technology should be a promising clean energy system after considering the high energy density,easy transportation/storage,matured synthesis technology and carbon-free nature of NH_(3) as well as high efficiency of SOFCs.However,the large-scale applications of direct-ammonia SOFCs(DASOFCs)are strongly limited by the inferior anti-sintering capability and catalytic activity for ammonia decomposition reaction of conventional nickel-based cermet anode.Herein,a slightly ruthenium(Ru)doping in perovskite oxides is proposed to promote the alloy nanoparticle exsolution,enabling better DA-SOFCs with enhanced power outputs and operational stability.After treating Ru-doped Pr_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.75)Ru_(0.05)O_(3-δ) single-phase perovskite in a reducing atmosphere,in addition to the formation of two layered Ruddlesden-Popper perovskites and Pr_(2)O_(3) nanoparticles(the same as the Ru-free counterpart,Pr_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.8)O_(3-δ)),the exsolution of CoFeRu-based alloy nanoparticles is remarkably promoted.Such reduced Pr_(0.6)Sr0.4Co_(0.2)Fe_(0.75)Ru_(0.05)O_(3-δ) composite anode shows superior catalytic activity and stability for NH_(3) decomposition reaction as well as anti-sintering capability in DA-SOFCs to those of reduced Pr0.6Sr0.4Co0.2Fe0.8O_(3-δ)due to the facilitated nanoparticle exsolution and stronger nanoparticle/substrate interaction.This work provides a facile and effective strategy to design highly active and durable anodes for DA-SOFCs,promoting large-scale applications of this technology.展开更多
Solid-state NMR(ssNMR)spectroscopy is a powerful technique for characterizing the surface sites of solid acids and organic intermediates formed during the acid catalyzed reaction.As a very useful probe molecule,ammoni...Solid-state NMR(ssNMR)spectroscopy is a powerful technique for characterizing the surface sites of solid acids and organic intermediates formed during the acid catalyzed reaction.As a very useful probe molecule,ammonia is often utilized to determine the density of solidacids’surface sites by ssNMR spectroscopy.The present mini-review summarizes some of the latest research developments on the quantitative characterization of the acid sites and carbenium ions during the zeolite catalytic reaction by ammonia probe-assisted ssNMR spectroscopy.展开更多
以天津市滨海地区粉砂为研究对象,采用室内批试验,研究了不同水溶液氨氮浓度作用下含水介质胶体的释放规律,表征了释放的胶体粒径和电位,揭示了含水介质固体颗粒和胶体对氨氮的吸附作用。结果表明:不同水溶液氨氮浓度作用下,含水介质释...以天津市滨海地区粉砂为研究对象,采用室内批试验,研究了不同水溶液氨氮浓度作用下含水介质胶体的释放规律,表征了释放的胶体粒径和电位,揭示了含水介质固体颗粒和胶体对氨氮的吸附作用。结果表明:不同水溶液氨氮浓度作用下,含水介质释放的胶体浓度、粒径和电位存在一个临界氨氮浓度。当水溶液氨氮浓度小于临界浓度时,释放的胶体浓度、粒径和电位都逐渐减小;大于临界浓度时,三者随水溶液氨氮浓度变化很小。临界氨氮浓度为70 mg/L时,含水介质释放的胶体浓度为1.4 g/L,胶体平均粒径和电位分别为2.1μm和-16 m V。含水介质固体颗粒对氨氮的吸附等温线符合线性模型。胶体对氨氮的吸附等温线符合对数曲线,吸附量随着水溶液氨氮浓度的增大先快速增加,然后变得缓慢。双电层理论和吸附电中和理论很好地揭示了含水介质释放的胶体浓度、粒径和电位的变化规律。展开更多
Since the availability of T4 RNA ligase, a great progress has been made in fields of synthesis of polynueleotides. However, all reactions were carried out in solvents. Though reactions in solvents favour the activity ...Since the availability of T4 RNA ligase, a great progress has been made in fields of synthesis of polynueleotides. However, all reactions were carried out in solvents. Though reactions in solvents favour the activity of enzyme, there still exist certain drawbacks, for instance, it takes a long time for separation and the recovery is展开更多
By making the use of the processes which includes separating trash and solid materials from the wastewater-ammonia stripping tower-UASB-biological oxidation pond, we have treated the wastewater which comes from the sw...By making the use of the processes which includes separating trash and solid materials from the wastewater-ammonia stripping tower-UASB-biological oxidation pond, we have treated the wastewater which comes from the swine factory. The treated wastewater can meet the primary standard of The People＇s Republic of China based on sewage discharge standards and the wastewater treatment project design contract （GBl8596-2001）, and the effluent will be used as irrigation-water. We introduce this project including the quality of influent and effluent and the flow scheme, the statement of every part, the investment and the effect, etc. The operation indicated that this process has many merits such as the stability in operation-effect and the convenience in management. So it will provide some help for the similar wastewater treatment.展开更多
基金supported by the National Natural Science Foundation of China(Nos.22179039 and 22005105)the Natural Science Foundation of Guangdong Province(No.2021A1515010395)the Pearl River Talent Recruitment Program(Nos.2019QN01C693 and 2021ZT09L392).
文摘Ammonia has been recognized as a promising fuel for solid oxide fuel cells(SOFCs)because of its relatively high hydrogen content and high energy density.However,the effective catalysis of ammonia on the surface of state-of-the-art anode greatly hinders the further development of direct ammonia SOFCs.In this study,we report our findings of surface activating and stabilizing of a Ni-based cermet anode for highly efficient and durable operation on ammonia fuel,achieved by a surface coating of CeO_(2)−δnanoparticles(NPs).When incorporated into a Ni-yttria-stabilized zirconia(Ni-YSZ)anode-supported single cell,the coatings demonstrate an improved electrochemical reaction activity and stability,achieving a high peak power density of 0.941 W·cm^(−2)at 700℃,and a promising stability of~60 h(degradation rate of 0.127%h^(−1)at 0.5 A·cm−2),much better than those of cells with a bare anode(~0.673 W·cm^(−2)and degradation rate of 0.294%h−1 at 0.5 A·cm^(-2)).The catalytic NPs significantly enhance the reaction activity toward the decomposition of ammonia and oxidation of hydrogen,especially at low temperatures(<700℃),as confirmed by the detailed distribution of relaxation time(DRT)analyses of the impedance spectra of the cells on NH3 fuel.
基金financially supported by the National Natural Science Foundation of China(Nos.22108121,21908106 and21878158)Jiangsu Natural Science Foundation(No.BK20190682)a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)。
文摘Fuel flexibility is one of the most distinguished advantages of solid oxide fuel cells(SOFCs)over other low-temperature fuel cells.Furthermore,the combination of ammonia fuel and SOFCs technology should be a promising clean energy system after considering the high energy density,easy transportation/storage,matured synthesis technology and carbon-free nature of NH_(3) as well as high efficiency of SOFCs.However,the large-scale applications of direct-ammonia SOFCs(DASOFCs)are strongly limited by the inferior anti-sintering capability and catalytic activity for ammonia decomposition reaction of conventional nickel-based cermet anode.Herein,a slightly ruthenium(Ru)doping in perovskite oxides is proposed to promote the alloy nanoparticle exsolution,enabling better DA-SOFCs with enhanced power outputs and operational stability.After treating Ru-doped Pr_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.75)Ru_(0.05)O_(3-δ) single-phase perovskite in a reducing atmosphere,in addition to the formation of two layered Ruddlesden-Popper perovskites and Pr_(2)O_(3) nanoparticles(the same as the Ru-free counterpart,Pr_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.8)O_(3-δ)),the exsolution of CoFeRu-based alloy nanoparticles is remarkably promoted.Such reduced Pr_(0.6)Sr0.4Co_(0.2)Fe_(0.75)Ru_(0.05)O_(3-δ) composite anode shows superior catalytic activity and stability for NH_(3) decomposition reaction as well as anti-sintering capability in DA-SOFCs to those of reduced Pr0.6Sr0.4Co0.2Fe0.8O_(3-δ)due to the facilitated nanoparticle exsolution and stronger nanoparticle/substrate interaction.This work provides a facile and effective strategy to design highly active and durable anodes for DA-SOFCs,promoting large-scale applications of this technology.
基金the National Natural Science Foundation of China(21972069)the Fundamental Research Funds for the Central Universities(Nankai University).
文摘Solid-state NMR(ssNMR)spectroscopy is a powerful technique for characterizing the surface sites of solid acids and organic intermediates formed during the acid catalyzed reaction.As a very useful probe molecule,ammonia is often utilized to determine the density of solidacids’surface sites by ssNMR spectroscopy.The present mini-review summarizes some of the latest research developments on the quantitative characterization of the acid sites and carbenium ions during the zeolite catalytic reaction by ammonia probe-assisted ssNMR spectroscopy.
文摘以天津市滨海地区粉砂为研究对象,采用室内批试验,研究了不同水溶液氨氮浓度作用下含水介质胶体的释放规律,表征了释放的胶体粒径和电位,揭示了含水介质固体颗粒和胶体对氨氮的吸附作用。结果表明:不同水溶液氨氮浓度作用下,含水介质释放的胶体浓度、粒径和电位存在一个临界氨氮浓度。当水溶液氨氮浓度小于临界浓度时,释放的胶体浓度、粒径和电位都逐渐减小;大于临界浓度时,三者随水溶液氨氮浓度变化很小。临界氨氮浓度为70 mg/L时,含水介质释放的胶体浓度为1.4 g/L,胶体平均粒径和电位分别为2.1μm和-16 m V。含水介质固体颗粒对氨氮的吸附等温线符合线性模型。胶体对氨氮的吸附等温线符合对数曲线,吸附量随着水溶液氨氮浓度的增大先快速增加,然后变得缓慢。双电层理论和吸附电中和理论很好地揭示了含水介质释放的胶体浓度、粒径和电位的变化规律。
文摘Since the availability of T4 RNA ligase, a great progress has been made in fields of synthesis of polynueleotides. However, all reactions were carried out in solvents. Though reactions in solvents favour the activity of enzyme, there still exist certain drawbacks, for instance, it takes a long time for separation and the recovery is
文摘By making the use of the processes which includes separating trash and solid materials from the wastewater-ammonia stripping tower-UASB-biological oxidation pond, we have treated the wastewater which comes from the swine factory. The treated wastewater can meet the primary standard of The People＇s Republic of China based on sewage discharge standards and the wastewater treatment project design contract （GBl8596-2001）, and the effluent will be used as irrigation-water. We introduce this project including the quality of influent and effluent and the flow scheme, the statement of every part, the investment and the effect, etc. The operation indicated that this process has many merits such as the stability in operation-effect and the convenience in management. So it will provide some help for the similar wastewater treatment.
