There have been ever-growing demands to develop advanced electrocatalysts for renewable energy conversion over the past decade.As a promising platform for advanced electrocatalysts,reduced graphene oxide(rGO)has attra...There have been ever-growing demands to develop advanced electrocatalysts for renewable energy conversion over the past decade.As a promising platform for advanced electrocatalysts,reduced graphene oxide(rGO)has attracted substantial research interests in a variety of electrochemical energy conversion reactions.Its versatile utility is mainly attributed to unique physical and chemical properties,such as high specific surface area,tunable electronic structure,and the feasibility of structural modification and functionalization.Here,a comprehensive discussion is provided upon recent advances in the material preparation,characterization,and the catalytic activity of rGO-based electrocatalysts for various electrochemical energy conversion reactions(water splitting,CO2 reduction reaction,N2 reduction reaction,and O2 reduction reaction).Major advantages of rGO and the related challenges for enhancing their catalytic performance are addressed.展开更多
Circulating microRNAs(miRNAs)play a pivotal role in the occurrence and development of acute myocardial infarction(AMI),and precise detection of them holds significant clinical implications.The development of luminol-b...Circulating microRNAs(miRNAs)play a pivotal role in the occurrence and development of acute myocardial infarction(AMI),and precise detection of them holds significant clinical implications.The development of luminol-based luminophores in the field of electrochemiluminescence(ECL)for miRNA detection has been significant,while their effectiveness is hindered by the instability of co-reactant hydrogen peroxide(H_(2)O_(2)).In this work,an iron single-atom catalyst(Fe-PNC)was employed for catalyzing the luminol-O2 ECL system to achieve ultra-sensitive detection of myocardial miRNA.Target miRNA triggers a hybridization chain reaction(HCR),resulting in the generation of a DNA product featuring multiple sticky ends that facilitate the attachment of Fe-PNC probes to the electrode surface.The Fe-PNC catalyst exhibits high promise and efficiency for the oxygen reduction reaction(ORR)in electrochemical energy conversion systems.The resulting ECL biosensor allowed ultrasensitive detection of myocardial miRNA with a low detection limit of 0.42 fM and a wide linear range from 1 fM to 1.0 nM.Additionally,it demonstrates exceptional performance when evaluated using serum samples collected from patients with AMI.This work expands the application of single-atom catalysis in ECL sensing and introduces novel perspectives for utilizing ECL in disease diagnosis.展开更多
The mechanisms of the CH2+ O2→ H2O+ CO and CH2+ O2→ H2+ CO2 reactions have been studied by performing ab initio CAS(8,8)/6-31G(d,p) calculations, and five intermediates(IMn) and eight transitions(TSn) have been ...The mechanisms of the CH2+ O2→ H2O+ CO and CH2+ O2→ H2+ CO2 reactions have been studied by performing ab initio CAS(8,8)/6-31G(d,p) calculations, and five intermediates(IMn) and eight transitions(TSn) have been located along the reaction paths. The predicted path for the CH2+ O2→ H2O+ CO is: CH2+ O2→ TS1→ IM1→ TS2→ IM2→ TS3→ IM3→ TS4→ IM4a→ TS5→ H2O+ CO. For the CH2+ O2→ H2+ CO2 reaction, there are two paths: (i) CH2+ O2→ TS1→ IM1→ TS2→ IM2→ TS3→ IM3→ TS6→ H2+ CO2 and (ii) CH2+ O2→ TS1→ IM1→ TS2→ IM2→ TS3→ IM3→ TS4→ IM4a→ TS7→ IM4b→ TS8→ H2+ CO2, with the latter path more favorable energetically.展开更多
A series of TiO2-SnO2 nano-sized composite photo-catalysts containing Sn (9.3%-30.1%) were prepared from TiCI4 and SnCl4·5H2O by using sol-gel, supercritical fluid dry and solid-phase reaction (SCFD) combination ...A series of TiO2-SnO2 nano-sized composite photo-catalysts containing Sn (9.3%-30.1%) were prepared from TiCI4 and SnCl4·5H2O by using sol-gel, supercritical fluid dry and solid-phase reaction (SCFD) combination technology. Characterizations with X-ray diffraction (XRD), transmission electron microscopy (TEM) and Fourier Transform Infrared Spectroscopy (FTIR) showed that, in addition to anatase type TiO2, a new active phase (Ti, Sn)O2 (with particle size of 2.0-4.3 nm) formed, and there were no SnO2 crystals observed in the range of the doping concentration studied. Photo-catalytic reaction of phenol was used as a model reaction to evaluate the catalytic activities of the obtained catalysts. Compared with pure TiO2 or Ti-Sn catalyst prepared with general sol-gel method, Ti-Sn nano-composite photo-catalyst thus obtained showed significant improvement in catalytic activity. The photo-catalytic degradation rate of phenol could reach as high as 93.5% after 7 h. The preparation conditions of the new phase (Ti, Sn)O2 were investigated and its catalytic mechanism was proposed. The photo-catalytic particles prepared using SCFD combination technology exhibited small particle size, large surface area and high activity.展开更多
The geometries of the reactants, transition states, intermediates and products for the titled reactions are optimized with CAS(17,13)/cc pVDZ, CAS(9,7)+1+2/cc pVDZ and CAS(9,7)+1+2/cc pVTZ. All stationary points are c...The geometries of the reactants, transition states, intermediates and products for the titled reactions are optimized with CAS(17,13)/cc pVDZ, CAS(9,7)+1+2/cc pVDZ and CAS(9,7)+1+2/cc pVTZ. All stationary points are characterized with vibrational analysis, and the rate constants for the titled reaction are computed with transition state theory. The obtained values are in good agreement with the experimental ones.展开更多
基金This study was supported by Korea Hydro&Nuclear Power Co.,Ltd.(No.:2018-Tech-21)the National Research Foundation of Korea(NRF)grant funded by the Korea government MSIT(2019M3E6A1064763).
文摘There have been ever-growing demands to develop advanced electrocatalysts for renewable energy conversion over the past decade.As a promising platform for advanced electrocatalysts,reduced graphene oxide(rGO)has attracted substantial research interests in a variety of electrochemical energy conversion reactions.Its versatile utility is mainly attributed to unique physical and chemical properties,such as high specific surface area,tunable electronic structure,and the feasibility of structural modification and functionalization.Here,a comprehensive discussion is provided upon recent advances in the material preparation,characterization,and the catalytic activity of rGO-based electrocatalysts for various electrochemical energy conversion reactions(water splitting,CO2 reduction reaction,N2 reduction reaction,and O2 reduction reaction).Major advantages of rGO and the related challenges for enhancing their catalytic performance are addressed.
基金supported by the National Natural Science Foundation of China(No.22004003)the Natural Science Foundation of Anhui Province for Distinguished Young Scholars(No.2008085J11)+2 种基金the Open Project Program of Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science(No.M2024-5)MOE,the Open Project of Engineering Research Center of Biofilm Water Purification and Utilization Technology of Ministry of Education(No.BWPU2023KF06)the Natural Science Research Project of Anhui Province Education Department(No.2023AH051116).
文摘Circulating microRNAs(miRNAs)play a pivotal role in the occurrence and development of acute myocardial infarction(AMI),and precise detection of them holds significant clinical implications.The development of luminol-based luminophores in the field of electrochemiluminescence(ECL)for miRNA detection has been significant,while their effectiveness is hindered by the instability of co-reactant hydrogen peroxide(H_(2)O_(2)).In this work,an iron single-atom catalyst(Fe-PNC)was employed for catalyzing the luminol-O2 ECL system to achieve ultra-sensitive detection of myocardial miRNA.Target miRNA triggers a hybridization chain reaction(HCR),resulting in the generation of a DNA product featuring multiple sticky ends that facilitate the attachment of Fe-PNC probes to the electrode surface.The Fe-PNC catalyst exhibits high promise and efficiency for the oxygen reduction reaction(ORR)in electrochemical energy conversion systems.The resulting ECL biosensor allowed ultrasensitive detection of myocardial miRNA with a low detection limit of 0.42 fM and a wide linear range from 1 fM to 1.0 nM.Additionally,it demonstrates exceptional performance when evaluated using serum samples collected from patients with AMI.This work expands the application of single-atom catalysis in ECL sensing and introduces novel perspectives for utilizing ECL in disease diagnosis.
文摘The mechanisms of the CH2+ O2→ H2O+ CO and CH2+ O2→ H2+ CO2 reactions have been studied by performing ab initio CAS(8,8)/6-31G(d,p) calculations, and five intermediates(IMn) and eight transitions(TSn) have been located along the reaction paths. The predicted path for the CH2+ O2→ H2O+ CO is: CH2+ O2→ TS1→ IM1→ TS2→ IM2→ TS3→ IM3→ TS4→ IM4a→ TS5→ H2O+ CO. For the CH2+ O2→ H2+ CO2 reaction, there are two paths: (i) CH2+ O2→ TS1→ IM1→ TS2→ IM2→ TS3→ IM3→ TS6→ H2+ CO2 and (ii) CH2+ O2→ TS1→ IM1→ TS2→ IM2→ TS3→ IM3→ TS4→ IM4a→ TS7→ IM4b→ TS8→ H2+ CO2, with the latter path more favorable energetically.
基金The authors thank the National Natural Scir nce Foun-dation of China(No.20076004)the National Development Project of High Technology(No.2001AA322030)the Doctoral Program of Higher Education(No.2000001005)for the financial support of this project.
文摘A series of TiO2-SnO2 nano-sized composite photo-catalysts containing Sn (9.3%-30.1%) were prepared from TiCI4 and SnCl4·5H2O by using sol-gel, supercritical fluid dry and solid-phase reaction (SCFD) combination technology. Characterizations with X-ray diffraction (XRD), transmission electron microscopy (TEM) and Fourier Transform Infrared Spectroscopy (FTIR) showed that, in addition to anatase type TiO2, a new active phase (Ti, Sn)O2 (with particle size of 2.0-4.3 nm) formed, and there were no SnO2 crystals observed in the range of the doping concentration studied. Photo-catalytic reaction of phenol was used as a model reaction to evaluate the catalytic activities of the obtained catalysts. Compared with pure TiO2 or Ti-Sn catalyst prepared with general sol-gel method, Ti-Sn nano-composite photo-catalyst thus obtained showed significant improvement in catalytic activity. The photo-catalytic degradation rate of phenol could reach as high as 93.5% after 7 h. The preparation conditions of the new phase (Ti, Sn)O2 were investigated and its catalytic mechanism was proposed. The photo-catalytic particles prepared using SCFD combination technology exhibited small particle size, large surface area and high activity.
文摘The geometries of the reactants, transition states, intermediates and products for the titled reactions are optimized with CAS(17,13)/cc pVDZ, CAS(9,7)+1+2/cc pVDZ and CAS(9,7)+1+2/cc pVTZ. All stationary points are characterized with vibrational analysis, and the rate constants for the titled reaction are computed with transition state theory. The obtained values are in good agreement with the experimental ones.