Resistive random-access memory(RRAM)is a promising technology to develop nonvolatile memory and artificial synaptic devices for brain-inspired neuromorphic computing.Here,we have developed a STO:Ag/SiO2 bilayer bas...Resistive random-access memory(RRAM)is a promising technology to develop nonvolatile memory and artificial synaptic devices for brain-inspired neuromorphic computing.Here,we have developed a STO:Ag/SiO2 bilayer based memristor that has exhibited a filamentary resistive switching with stable endurance and long-term data retention ability.The memristor also exhibits a tunable resistance modulation under positive and negative pulse trains,which could fully mimic the potentiation and depression behavior like a bio-synapse.Several synaptic plasticity functions,including long-term potentiation(LTP)and long-term depression(LTD),paired-pulsed facilitation(PPF),spike-rate-dependent-plasticity(SRDP),and post-tetanic potentiation(PTP),are faithfully implemented with the fabricated memristor.Moreover,to demonstrate the feasibility of our memristor synapse for neuromorphic applications,spike-timedependent plasticity(STDP)is also investigated.Based on conductive atomic force microscopy observations and electrical transport model analyses,it can be concluded that it is the controlled formation and rupture of Ag filaments that are responsible for the resistive switching while exhibiting a switching ratio of~10;along with a good endurance and stability suitable for nonvolatile memory applications.Before fully electroforming,the gradual conductance modulation of Ag/STO:Ag/SiO2/p++-Si memristor can be realized,and the working mechanism could be explained by the succeeding growth and contraction of Ag filaments promoted by a redox reaction.This newly fabricated memristor may enable the development of nonvolatile memory and realize controllable resistance/weight modulation when applied as an artificial synapse for neuromorphic computing.展开更多
The Ag/SiO2 nanoparticles had been successfully synthesized. The Ag/SiO2 nano- particles can be an excellent catalyst for the synthesis of ultraviolet absorber benzotriazole by catalytic hydrogenation. The synthesis r...The Ag/SiO2 nanoparticles had been successfully synthesized. The Ag/SiO2 nano- particles can be an excellent catalyst for the synthesis of ultraviolet absorber benzotriazole by catalytic hydrogenation. The synthesis route is very efficient with less pollution and excellent yields. It is also easy to industrialized production.展开更多
Methyl glycolate is a good solvent and can be used as feedstock for the synthesis of some important organic chemicals. Catalytic hydrogenation of dimethyl oxalate (DMO) over copper-silver catalyst supported on silic...Methyl glycolate is a good solvent and can be used as feedstock for the synthesis of some important organic chemicals. Catalytic hydrogenation of dimethyl oxalate (DMO) over copper-silver catalyst supported on silica was studied. The Cu-Ag/SiO2 catalyst supported on silica sol was prepared by homogeneous deposition-precipitation of the mixture of aqueous euprammonia complex and silica sol. The proper active temperature of Cu-Ag/SiO2 catalyst for hydrogenation of DMO was 523-623 K. The most preferable reaction conditions for methyl glycolate (MG) were optimized: temperature at 468-478 K, 40-60 mesh catalyst diameter, H2/DMO ratio 40, and 1.0 h^-1 of LHSV.展开更多
The vapor-phase synthesis of 3-methylindole over Ag/SiO2 doped with ZnO was investigated.The catalysts were characterized by XRD,H2-TPR,NH3-TPD and TG techniques.The results indicated that ZnO promoter greatly enhance...The vapor-phase synthesis of 3-methylindole over Ag/SiO2 doped with ZnO was investigated.The catalysts were characterized by XRD,H2-TPR,NH3-TPD and TG techniques.The results indicated that ZnO promoter greatly enhanced the initial activity of the catalyst but disfavored its stability.H2-TPR and XRD results showed that the reduction peak of Ag2O shifted to higher temperature and the intensity of silver diffraction peaks was much weaker after the addition of ZnO promoter to Ag/SiO2.This indicated that there existed the interaction between Ag2O and SiO2-ZnO which promoted the silver particles dispersing on the support and inhibited the sintering of silver during the reaction.NH3-TPD and TG results revealed that the acid amounts of the catalyst and coking increased after adding ZnO to Ag/SiO2,which resulted in the deactivation of Ag/SiO2-ZnO catalyst rapidly.展开更多
基金financially supported by the National Science Funds for Excellent Young Scholars of China(no.61822106)the Natural Science Foundation of China(no.U19A2070)。
摘要Resistive random-access memory(RRAM)is a promising technology to develop nonvolatile memory and artificial synaptic devices for brain-inspired neuromorphic computing.Here,we have developed a STO:Ag/SiO2 bilayer based memristor that has exhibited a filamentary resistive switching with stable endurance and long-term data retention ability.The memristor also exhibits a tunable resistance modulation under positive and negative pulse trains,which could fully mimic the potentiation and depression behavior like a bio-synapse.Several synaptic plasticity functions,including long-term potentiation(LTP)and long-term depression(LTD),paired-pulsed facilitation(PPF),spike-rate-dependent-plasticity(SRDP),and post-tetanic potentiation(PTP),are faithfully implemented with the fabricated memristor.Moreover,to demonstrate the feasibility of our memristor synapse for neuromorphic applications,spike-timedependent plasticity(STDP)is also investigated.Based on conductive atomic force microscopy observations and electrical transport model analyses,it can be concluded that it is the controlled formation and rupture of Ag filaments that are responsible for the resistive switching while exhibiting a switching ratio of~10;along with a good endurance and stability suitable for nonvolatile memory applications.Before fully electroforming,the gradual conductance modulation of Ag/STO:Ag/SiO2/p++-Si memristor can be realized,and the working mechanism could be explained by the succeeding growth and contraction of Ag filaments promoted by a redox reaction.This newly fabricated memristor may enable the development of nonvolatile memory and realize controllable resistance/weight modulation when applied as an artificial synapse for neuromorphic computing.
基金supported by research fund of Key Laboratory for Advanced Technology in Environmental Protection of Jiangsu Province (No. AE201127)
摘要The Ag/SiO2 nanoparticles had been successfully synthesized. The Ag/SiO2 nano- particles can be an excellent catalyst for the synthesis of ultraviolet absorber benzotriazole by catalytic hydrogenation. The synthesis route is very efficient with less pollution and excellent yields. It is also easy to industrialized production.
摘要Methyl glycolate is a good solvent and can be used as feedstock for the synthesis of some important organic chemicals. Catalytic hydrogenation of dimethyl oxalate (DMO) over copper-silver catalyst supported on silica was studied. The Cu-Ag/SiO2 catalyst supported on silica sol was prepared by homogeneous deposition-precipitation of the mixture of aqueous euprammonia complex and silica sol. The proper active temperature of Cu-Ag/SiO2 catalyst for hydrogenation of DMO was 523-623 K. The most preferable reaction conditions for methyl glycolate (MG) were optimized: temperature at 468-478 K, 40-60 mesh catalyst diameter, H2/DMO ratio 40, and 1.0 h^-1 of LHSV.
基金supported by the Innovative Research Team in University of Liaoning(No.2008T106)
摘要The vapor-phase synthesis of 3-methylindole over Ag/SiO2 doped with ZnO was investigated.The catalysts were characterized by XRD,H2-TPR,NH3-TPD and TG techniques.The results indicated that ZnO promoter greatly enhanced the initial activity of the catalyst but disfavored its stability.H2-TPR and XRD results showed that the reduction peak of Ag2O shifted to higher temperature and the intensity of silver diffraction peaks was much weaker after the addition of ZnO promoter to Ag/SiO2.This indicated that there existed the interaction between Ag2O and SiO2-ZnO which promoted the silver particles dispersing on the support and inhibited the sintering of silver during the reaction.NH3-TPD and TG results revealed that the acid amounts of the catalyst and coking increased after adding ZnO to Ag/SiO2,which resulted in the deactivation of Ag/SiO2-ZnO catalyst rapidly.