The electrocatalytic conversion of CO_(2) into valuable chemical feedstocks using renewable electricity offers a compelling strategy for closing the carbon loop.While copper-based materials are effective in catalyzing...The electrocatalytic conversion of CO_(2) into valuable chemical feedstocks using renewable electricity offers a compelling strategy for closing the carbon loop.While copper-based materials are effective in catalyzing CO_(2) to C_(2+)products,the instability of Cu^(+)species,which tend to reduce to Cu~0 at cathodic potentials during CO_(2) reduction,poses a significant challenge.Here,we report the development of SmCu_(2)O and investigate the influence of f-d orbital hybridization on the CO_(2) reduction reaction (CO_(2)RR).Supported by density functional theory (DFT) calculations,our experimental results demonstrate that hybridization between Sm^(3+)4f and Cu^(+)3d orbitals not only improves the adsorption of *CO intermediates and increases CO coverage to stabilize Cu^(+) but also facilitates CO_(2) activation and lowers the energy barriers for CAC coupling.Notably,Sm-Cu_(2)O achieves a Faradaic efficiency for C_(2)H_(4) that is 38%higher than that of undoped Cu_(2)O.Additionally,it sustains its catalytic activity over an extended operational period exceeding 7 h,compared to merely 2 h for the undoped sample.This research highlights the potential of fd orbital hybridization in enhancing the efficacy of copper-based catalysts for CO_(2)RR,pointing towards a promising direction for the development of durable,high-performance electrocatalysts for sustainable chemical synthesis.展开更多
The key to fully understanding water-solid interfaces relies on the microscopic nature of hydrogen bond networks,including their atomic structures, interfacial interactions, and dynamic behaviors. Here, we report the ...The key to fully understanding water-solid interfaces relies on the microscopic nature of hydrogen bond networks,including their atomic structures, interfacial interactions, and dynamic behaviors. Here, we report the observation of two types of simplest water chains on Au(111) surface which is expected unstable according to the rules of hydrogen network on noble metal surfaces. A common feature at the end of chain structures is revealed in high resolution scanning tunneling microscopy images. To explain the stability in observed hydrogen bond networks,we propose a structure model of the water chains terminated with a hydroxyl group. The model is consistent with detailed image analysis and molecular manipulation. The observation of simplest water chains suggests a new platform for exploring fundamental physics in hydrogen bond networks on surfaces.展开更多
A fiber-optic Raman spectrum sensor system is used for the fast diagnosis of esophageal cancer during clinical endoscopic examination.The system contains a 785nm exciting laser,a Raman fiber-optic probe with 7 large c...A fiber-optic Raman spectrum sensor system is used for the fast diagnosis of esophageal cancer during clinical endoscopic examination.The system contains a 785nm exciting laser,a Raman fiber-optic probe with 7 large core fibers and a focus lens,and a highly sensitive spectrum meter.The Raman spectrum of the tissue could be obtained within 1 second by using such a system. A signal baseline removal and denoising technology is used to improve the signal quality.A novel signal feature extraction method for differentiating the normal and esophageal cancer tissues is proposed,based on the differences in half-height width(HHW)in 1200cm^-1 to 1400cm^-1 frequency band and the ratios of the spectral integral energy between 1600cm^-1-1700cm^-1 and 1500cm^-1- 1600cm^-1 band.It shows a high specificity and effectivity for the diagnosis of esophageal cancer.展开更多
基金Financial support from the National Natural Science Foundation of China(grant nos.22379006,21575016,U20A20154,22279005)from the National Program for Support of Top-notch Young Professionals is gratefully acknowledged。
文摘The electrocatalytic conversion of CO_(2) into valuable chemical feedstocks using renewable electricity offers a compelling strategy for closing the carbon loop.While copper-based materials are effective in catalyzing CO_(2) to C_(2+)products,the instability of Cu^(+)species,which tend to reduce to Cu~0 at cathodic potentials during CO_(2) reduction,poses a significant challenge.Here,we report the development of SmCu_(2)O and investigate the influence of f-d orbital hybridization on the CO_(2) reduction reaction (CO_(2)RR).Supported by density functional theory (DFT) calculations,our experimental results demonstrate that hybridization between Sm^(3+)4f and Cu^(+)3d orbitals not only improves the adsorption of *CO intermediates and increases CO coverage to stabilize Cu^(+) but also facilitates CO_(2) activation and lowers the energy barriers for CAC coupling.Notably,Sm-Cu_(2)O achieves a Faradaic efficiency for C_(2)H_(4) that is 38%higher than that of undoped Cu_(2)O.Additionally,it sustains its catalytic activity over an extended operational period exceeding 7 h,compared to merely 2 h for the undoped sample.This research highlights the potential of fd orbital hybridization in enhancing the efficacy of copper-based catalysts for CO_(2)RR,pointing towards a promising direction for the development of durable,high-performance electrocatalysts for sustainable chemical synthesis.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11774395 and 91753136the Beijing Natural Science Foundation under Grant No 4181003the Strategic Priority Research Program(B)of the Chinese Academy of Sciences under Grant Nos XDB30201000 and XDB28000000
文摘The key to fully understanding water-solid interfaces relies on the microscopic nature of hydrogen bond networks,including their atomic structures, interfacial interactions, and dynamic behaviors. Here, we report the observation of two types of simplest water chains on Au(111) surface which is expected unstable according to the rules of hydrogen network on noble metal surfaces. A common feature at the end of chain structures is revealed in high resolution scanning tunneling microscopy images. To explain the stability in observed hydrogen bond networks,we propose a structure model of the water chains terminated with a hydroxyl group. The model is consistent with detailed image analysis and molecular manipulation. The observation of simplest water chains suggests a new platform for exploring fundamental physics in hydrogen bond networks on surfaces.
基金multicenter clinical study of endoscopic diagnosis of early esophageal cancer(Grant No.SWH2016ZDCX3007)the State 111 Project(Grant No.B14039)+3 种基金Application of endoscopic minimally invasive technique in diagnosis and treatment of digestive tract injury and disease(Grant No.SWH2016ZDCX2011)Study of effect on fibroblast transdifferentiation and prevention of postoperative esophagus stenosis through regulating the TRADD(Grant No. 81470907)the National Natural Science Foundation of China(NSFC)(Grant Nos.51627806and 51875091)Application of Raman imaging in the diagnosis of gastric cancer(Grant No. cstc2015shmszx 10017).
文摘A fiber-optic Raman spectrum sensor system is used for the fast diagnosis of esophageal cancer during clinical endoscopic examination.The system contains a 785nm exciting laser,a Raman fiber-optic probe with 7 large core fibers and a focus lens,and a highly sensitive spectrum meter.The Raman spectrum of the tissue could be obtained within 1 second by using such a system. A signal baseline removal and denoising technology is used to improve the signal quality.A novel signal feature extraction method for differentiating the normal and esophageal cancer tissues is proposed,based on the differences in half-height width(HHW)in 1200cm^-1 to 1400cm^-1 frequency band and the ratios of the spectral integral energy between 1600cm^-1-1700cm^-1 and 1500cm^-1- 1600cm^-1 band.It shows a high specificity and effectivity for the diagnosis of esophageal cancer.
