The key to obtaining high intrinsic catalytic activity of Me-N_(x)-C electrocatalysts for Zn-air batteries is to form high-density bifunctional Me-N_(x) active sites during the pyrolysis of the precursor while maintai...The key to obtaining high intrinsic catalytic activity of Me-N_(x)-C electrocatalysts for Zn-air batteries is to form high-density bifunctional Me-N_(x) active sites during the pyrolysis of the precursor while maintaining structural stability.In this study,a host-vip spatial confinement strategy was utilized to synthesize a composite catalyst consisting of Co_(3)Fe_(7) nanoparticles confined in an N-doped carbon network.The coupling between the host(MIL-88B)and vip(cobalt porphyrin,CoPP)produces highdensity bimetallic atomic active sites.By controlling the mass of vip molecules,it is possible to construct precursors with the highest activity potential.The Co_(3)Fe_(7)/NC material with a certain amount of the vip displays a better electrocatalytic performance for both oxygen reduction reaction and oxygen evolution reaction with a half-wave potential(E_(1/2))of 0.85 V and an overpotential of 1.59 V at 10 mAcm^(-2),respectively.The specific structure of bimetallic active centers is verified to be FeN2-CoN_(4) using experimental characterizations,and the oxygen reaction mechanism is explored by in-situ characterization techniques and first-principles calculations.The Zn-air battery assembled with Co_(3)Fe_(7)/NC cathode exhibits a remarkable open-circuit voltage of 1.52 V,an exceptional peak power density of 248.1mWcm^(-2),and stable cycling stability over 1000 h.Particularly,the corresponding flexible Zn-air battery affords prominent cycling performance under different bending angles.This study supplies the idea and method of designing catalysts with specific structures at the atomic and electronic scales for breaking through the large-scale application of electrocatalysts based on oxygen reactions in fuel cells/metal-air batteries.展开更多
Acetone detection is crucial for diagnosing diseases such as diabetes and lung cancer.Therefore,it is essential to design a room-temperature acetone gas sensor with fast response and recovery times,high sensitivity,hi...Acetone detection is crucial for diagnosing diseases such as diabetes and lung cancer.Therefore,it is essential to design a room-temperature acetone gas sensor with fast response and recovery times,high sensitivity,high selectivity,and a low detection limit.However,current acetone gas sensors face challenges in achieving high-selectivity detection at room tempera-ture.This study primarily utilizes self-assembled organic monolayer functionalized MIL-88B to prepare selectivity acetone sensors.The results show that the detection sensitivity of the improved sensor to acetone is significantly improved.Com-pared with the MIL-88B sensor(0.1 ppm),the response value of the MIL-88B@3-aminopropyltrimethoxysilane(APTMS)sensor is increased by about 61.9%.The response to 10 ppm acetone is 83,and the selectivity is greatly improved at room temperature.This can be attributed to the chemical interactions between acetone molecules and APTMS on the sensor sur-face,which improves the sensor's specific recognition ability for acetone.Additionally,the sensor exhibits better stability and shorter response and recovery times.Consequently,the APTMS functionalization of MIL-88B presents an effective method for preparing room-temperature acetone sensors,combining high sensitivity and selectivity,and offering potential for non-invasive disease diagnosis.展开更多
基金supported by the National Natural Science Foundation of China(Nos.22008058)Natural Science Foundation of Hubei Province(No.2023AFB1010,2022CFB958)+5 种基金Key Project of Scientific Plan of Education Department of Hubei Province(No.D20232501)the Natural Science Foundation of Zhejiang Province(LQ23E020002)Wenzhou Key Scientific and Technological Innovation Research Project(ZG2023053)Wenzhou Natural Science Foundation(G20220019)Cooperation between industry and education project of Ministry of Education(220601318235513)Wenzhou Science and Technology Association Serves Scientific and Technological Innovation Projects(KJFW0201).
文摘The key to obtaining high intrinsic catalytic activity of Me-N_(x)-C electrocatalysts for Zn-air batteries is to form high-density bifunctional Me-N_(x) active sites during the pyrolysis of the precursor while maintaining structural stability.In this study,a host-vip spatial confinement strategy was utilized to synthesize a composite catalyst consisting of Co_(3)Fe_(7) nanoparticles confined in an N-doped carbon network.The coupling between the host(MIL-88B)and vip(cobalt porphyrin,CoPP)produces highdensity bimetallic atomic active sites.By controlling the mass of vip molecules,it is possible to construct precursors with the highest activity potential.The Co_(3)Fe_(7)/NC material with a certain amount of the vip displays a better electrocatalytic performance for both oxygen reduction reaction and oxygen evolution reaction with a half-wave potential(E_(1/2))of 0.85 V and an overpotential of 1.59 V at 10 mAcm^(-2),respectively.The specific structure of bimetallic active centers is verified to be FeN2-CoN_(4) using experimental characterizations,and the oxygen reaction mechanism is explored by in-situ characterization techniques and first-principles calculations.The Zn-air battery assembled with Co_(3)Fe_(7)/NC cathode exhibits a remarkable open-circuit voltage of 1.52 V,an exceptional peak power density of 248.1mWcm^(-2),and stable cycling stability over 1000 h.Particularly,the corresponding flexible Zn-air battery affords prominent cycling performance under different bending angles.This study supplies the idea and method of designing catalysts with specific structures at the atomic and electronic scales for breaking through the large-scale application of electrocatalysts based on oxygen reactions in fuel cells/metal-air batteries.
基金supported by the National Natural Science Foundation of China(62104063,61974040)the China Postdoctoral Science Foundation(2021M701055,2022T150188)Key Scientific and Technological Project of Henan Provinces(232102221006).
文摘Acetone detection is crucial for diagnosing diseases such as diabetes and lung cancer.Therefore,it is essential to design a room-temperature acetone gas sensor with fast response and recovery times,high sensitivity,high selectivity,and a low detection limit.However,current acetone gas sensors face challenges in achieving high-selectivity detection at room tempera-ture.This study primarily utilizes self-assembled organic monolayer functionalized MIL-88B to prepare selectivity acetone sensors.The results show that the detection sensitivity of the improved sensor to acetone is significantly improved.Com-pared with the MIL-88B sensor(0.1 ppm),the response value of the MIL-88B@3-aminopropyltrimethoxysilane(APTMS)sensor is increased by about 61.9%.The response to 10 ppm acetone is 83,and the selectivity is greatly improved at room temperature.This can be attributed to the chemical interactions between acetone molecules and APTMS on the sensor sur-face,which improves the sensor's specific recognition ability for acetone.Additionally,the sensor exhibits better stability and shorter response and recovery times.Consequently,the APTMS functionalization of MIL-88B presents an effective method for preparing room-temperature acetone sensors,combining high sensitivity and selectivity,and offering potential for non-invasive disease diagnosis.
