Designing highly active and stable electrocatalysts of oxygen evolution reaction(OER)is one of the crucial challenges.In this study,a novel OER electrocatalyst,NiFe-MIL-53 modified with ultra-low rhodium(Rh@NiFe-MIL-5...Designing highly active and stable electrocatalysts of oxygen evolution reaction(OER)is one of the crucial challenges.In this study,a novel OER electrocatalyst,NiFe-MIL-53 modified with ultra-low rhodium(Rh@NiFe-MIL-53),is successfully prepared via the hydrothermal method.In-situ Raman spectroscopy and electrochemical impedance spectroscopy reveal that the doped Rh accelerates the phase transformation of NiFe-MIL-53 and the in-situ formed Rh@NiFeOOH is the actual active species.More importantly,the enhanced reversibility of electrochemical reconstruction between NiFeOOH and NiFe(OH)_(2)after doping Rh is beneficial for improving the electrochemical stability of the catalyst.X-ray photoelectron spectroscopy spectra show the strong electronic interaction between single-atom Rh and Ni/Fe in Rh@NiFeOOH.Furthermore,theoretical calculations confirm that the integration of single-atom Rh into the NiFeOOH successfully reduces the band gap,regulates the d-band center(εd),accelerates the charge transfer,and optimizes the adsorption behavior of oxygen-containing intermediates,thereby lowering the energy barrier of rate-determining steps.Consequently,the optimized Rh@NiFe-MIL-53 exhibits excellent OER activity(240 mV)with a small Tafel slope of 48.2 mV dec^(-1)and long-term durability(over1270 h at 10 m A cm^(-2)and 110 h at 200 mA cm^(-2)).This work presents a new perspective on designing highly efficient OER electrocatalysts.展开更多
Objective:To design and implement a specialized nurse decision support system in the Department of Neurology and explore its effectiveness in preventing stroke-associated pneumonia(SAP).Methods:A decision support modu...Objective:To design and implement a specialized nurse decision support system in the Department of Neurology and explore its effectiveness in preventing stroke-associated pneumonia(SAP).Methods:A decision support module for specialized nurses was developed based on SAP-graded prevention strategies.A total of 664 neurology inpatients admitted to The First People’s Hospital of Xuzhou between July 2023 and September 2023 were selected as the conventional group,receiving standard nursing care.Another 704 neurology inpatients admitted between October 2023 and December 2023 were selected as the experimental group,receiving SAP-graded prevention strategies under the specialized nurse decision support system.The incidence of SAP in the two groups was compared.The occurrence of SAP was recorded using the Acute Ischemic Stroke-Associated Pneumonia Risk(A2DS2)scoring system.Swallowing function was evaluated using the Water Swallow Test(WST),and quality of life was assessed using the Swallowing Quality of Life(SWAL-QOL)scale.Results:The incidence of SAP in the experimental group was significantly lower than in the conventional group(P<0.05).After nursing interventions,the WST scores in the experimental group were lower,while the SWAL-QOL scores were higher compared to the conventional group(P<0.05).Conclusion:The design and implementation of a specialized nurse decision support system in the Department of Neurology significantly reduced the incidence of SAP in neurology inpatients,improved swallowing function,and enhanced quality of life.This approach shows promise for widespread application.展开更多
Transition metal chalcogenides will be in situ transformed into metal oxyhydroxides during oxygen evolution reaction(OER) process in alkaline medium.However,most of these compounds only undergo surface reconstruction ...Transition metal chalcogenides will be in situ transformed into metal oxyhydroxides during oxygen evolution reaction(OER) process in alkaline medium.However,most of these compounds only undergo surface reconstruction under operating conditions,which contains a large percentage of inactive atoms in the core,thus limiting the exposure of the active sites.Here,we synthesize a Ni-Mo-Se precatalyst with three-dimensional hierarchical structure and develop a facile on-site electrochemical activation strategy for achieving deep reconstruction of the precatalyst.Using the combination of multiple spectroscopic characterizations and high resolution electron microscopy techniques,we unravel that the Ni-Mo-Se precatalyst is deeply reconstructed into γ-NiOOH with co-leaching of Mo and Se after the anodic oxidation.Such flower-like γ-NiOOH is constituted by distorted ultrathin nanosheets with a thickness of ~4.5 nm and contains abundant intercalated species such as water and OH^(-)/CO_(3)^(2-) thus offering a large quantity of accessible active sites.To reach the current density of 10 mA cm^(-2),the derived electrode requires an overpotential of only 244 mV,outperforming almost all the reported analogues.This work highlights the reconstruction chemistry and provides a simple method for the preparation of efficient OER electrocatalyst.展开更多
Tuning surface electron transfer process by sulfur(S)-vacancies engineering is an efficient strategy to develop high-efficient catalysts for electroreduction N_(2) reaction(NRR). Herein, the distinct Sb_(2)S_(3) nanor...Tuning surface electron transfer process by sulfur(S)-vacancies engineering is an efficient strategy to develop high-efficient catalysts for electroreduction N_(2) reaction(NRR). Herein, the distinct Sb_(2)S_(3) nanorods with S-vacancies(Sv-Sb_(2)S_(3)) have been synthesized by a simple twostep method including hydrothermal and hydrogenation in H_(2)/Ar atmosphere, which shows improved performance for NRR with the NH_(3) yield rate of 10.85 μg h^(-1) mgcat^(-1) at-0.4 V vs. RHE, the faradaic efficiency(FE) of 3.75% at -0.3 V vs. RHE and excellent stability for 24 h, largely outperforming bulk Sb_(2)S_(3). X-ray photoelectron spectroscopy(XPS) and density function theory(DFT) calculations demonstrate that the abundant S-vacancies can create an electron-deficient environment and modulate the electron delocalization in Sv-Sb_(2)S_(3), which can not only facilitate the N_(2) molecule adsorption, but also activate the N≡N, resulting in the enhanced performance for NRR.展开更多
The intrinsic activity and durability of oxygen evolution reaction(OER)electrocatalysts are mainly dominated by the surface and interface properties of active materials.Herein,a core-shell heterogeneous structure(NF/N...The intrinsic activity and durability of oxygen evolution reaction(OER)electrocatalysts are mainly dominated by the surface and interface properties of active materials.Herein,a core-shell heterogeneous structure(NF/NiSe@Fe_(2)O_(3))is fabricated via two-step hydrothermal method,which exhibits a low overpotential of 220 mV(or 282 mV)at 10 mA/cm^(2)(or 200 mA/cm^(2)),a small Tafel slope of 36.9 mV/dec,and long-term stability(-230 h)in 1 mol/L KOH for OER.X-ray photoelectron spectroscopy and X-ray absorption spectroscopy reveal the(oxy)hydroxide-rich surface and strong coupling interface between NiSe and Fe_(2)O_(3)via the Fe-Se bond.Density functional theory calculation suggests that the d-band center and electronic state of NiSe@Fe_(2)O_(3)heterojunction are well optimized due to the formation of Fe-Se bond,which is favorable for the enhanced OER activity because of the easy adsorption of oxygen-containing intermediates and desorption of O^(2)in the OER process.In addition,the unique core-shell structure and robust bonding interface are responsible for the good stability for OER.This work provides fundamental insights on the bonding effect that determine the performance of OER electrocatalyst.展开更多
基金Natural Science Foundation of China(Grant No.NSFC-22072062,22202098)。
文摘Designing highly active and stable electrocatalysts of oxygen evolution reaction(OER)is one of the crucial challenges.In this study,a novel OER electrocatalyst,NiFe-MIL-53 modified with ultra-low rhodium(Rh@NiFe-MIL-53),is successfully prepared via the hydrothermal method.In-situ Raman spectroscopy and electrochemical impedance spectroscopy reveal that the doped Rh accelerates the phase transformation of NiFe-MIL-53 and the in-situ formed Rh@NiFeOOH is the actual active species.More importantly,the enhanced reversibility of electrochemical reconstruction between NiFeOOH and NiFe(OH)_(2)after doping Rh is beneficial for improving the electrochemical stability of the catalyst.X-ray photoelectron spectroscopy spectra show the strong electronic interaction between single-atom Rh and Ni/Fe in Rh@NiFeOOH.Furthermore,theoretical calculations confirm that the integration of single-atom Rh into the NiFeOOH successfully reduces the band gap,regulates the d-band center(εd),accelerates the charge transfer,and optimizes the adsorption behavior of oxygen-containing intermediates,thereby lowering the energy barrier of rate-determining steps.Consequently,the optimized Rh@NiFe-MIL-53 exhibits excellent OER activity(240 mV)with a small Tafel slope of 48.2 mV dec^(-1)and long-term durability(over1270 h at 10 m A cm^(-2)and 110 h at 200 mA cm^(-2)).This work presents a new perspective on designing highly efficient OER electrocatalysts.
文摘Objective:To design and implement a specialized nurse decision support system in the Department of Neurology and explore its effectiveness in preventing stroke-associated pneumonia(SAP).Methods:A decision support module for specialized nurses was developed based on SAP-graded prevention strategies.A total of 664 neurology inpatients admitted to The First People’s Hospital of Xuzhou between July 2023 and September 2023 were selected as the conventional group,receiving standard nursing care.Another 704 neurology inpatients admitted between October 2023 and December 2023 were selected as the experimental group,receiving SAP-graded prevention strategies under the specialized nurse decision support system.The incidence of SAP in the two groups was compared.The occurrence of SAP was recorded using the Acute Ischemic Stroke-Associated Pneumonia Risk(A2DS2)scoring system.Swallowing function was evaluated using the Water Swallow Test(WST),and quality of life was assessed using the Swallowing Quality of Life(SWAL-QOL)scale.Results:The incidence of SAP in the experimental group was significantly lower than in the conventional group(P<0.05).After nursing interventions,the WST scores in the experimental group were lower,while the SWAL-QOL scores were higher compared to the conventional group(P<0.05).Conclusion:The design and implementation of a specialized nurse decision support system in the Department of Neurology significantly reduced the incidence of SAP in neurology inpatients,improved swallowing function,and enhanced quality of life.This approach shows promise for widespread application.
基金supported by the grants from the Natural Science Foundation of China (22072062)。
文摘Transition metal chalcogenides will be in situ transformed into metal oxyhydroxides during oxygen evolution reaction(OER) process in alkaline medium.However,most of these compounds only undergo surface reconstruction under operating conditions,which contains a large percentage of inactive atoms in the core,thus limiting the exposure of the active sites.Here,we synthesize a Ni-Mo-Se precatalyst with three-dimensional hierarchical structure and develop a facile on-site electrochemical activation strategy for achieving deep reconstruction of the precatalyst.Using the combination of multiple spectroscopic characterizations and high resolution electron microscopy techniques,we unravel that the Ni-Mo-Se precatalyst is deeply reconstructed into γ-NiOOH with co-leaching of Mo and Se after the anodic oxidation.Such flower-like γ-NiOOH is constituted by distorted ultrathin nanosheets with a thickness of ~4.5 nm and contains abundant intercalated species such as water and OH^(-)/CO_(3)^(2-) thus offering a large quantity of accessible active sites.To reach the current density of 10 mA cm^(-2),the derived electrode requires an overpotential of only 244 mV,outperforming almost all the reported analogues.This work highlights the reconstruction chemistry and provides a simple method for the preparation of efficient OER electrocatalyst.
基金supported by Natural Science Foundation of China (NSFC no. 21673105)the Science and Technology Program of Gansu Province of China (Grant No.1717JR5RA194)。
文摘Tuning surface electron transfer process by sulfur(S)-vacancies engineering is an efficient strategy to develop high-efficient catalysts for electroreduction N_(2) reaction(NRR). Herein, the distinct Sb_(2)S_(3) nanorods with S-vacancies(Sv-Sb_(2)S_(3)) have been synthesized by a simple twostep method including hydrothermal and hydrogenation in H_(2)/Ar atmosphere, which shows improved performance for NRR with the NH_(3) yield rate of 10.85 μg h^(-1) mgcat^(-1) at-0.4 V vs. RHE, the faradaic efficiency(FE) of 3.75% at -0.3 V vs. RHE and excellent stability for 24 h, largely outperforming bulk Sb_(2)S_(3). X-ray photoelectron spectroscopy(XPS) and density function theory(DFT) calculations demonstrate that the abundant S-vacancies can create an electron-deficient environment and modulate the electron delocalization in Sv-Sb_(2)S_(3), which can not only facilitate the N_(2) molecule adsorption, but also activate the N≡N, resulting in the enhanced performance for NRR.
基金supported by the National Natural Science Foundation of China (21673105)the support received from NSF under the award numbers OIA-1539035 and CHE-1539035supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Award No. DE-AC02-06CH11357
文摘The intrinsic activity and durability of oxygen evolution reaction(OER)electrocatalysts are mainly dominated by the surface and interface properties of active materials.Herein,a core-shell heterogeneous structure(NF/NiSe@Fe_(2)O_(3))is fabricated via two-step hydrothermal method,which exhibits a low overpotential of 220 mV(or 282 mV)at 10 mA/cm^(2)(or 200 mA/cm^(2)),a small Tafel slope of 36.9 mV/dec,and long-term stability(-230 h)in 1 mol/L KOH for OER.X-ray photoelectron spectroscopy and X-ray absorption spectroscopy reveal the(oxy)hydroxide-rich surface and strong coupling interface between NiSe and Fe_(2)O_(3)via the Fe-Se bond.Density functional theory calculation suggests that the d-band center and electronic state of NiSe@Fe_(2)O_(3)heterojunction are well optimized due to the formation of Fe-Se bond,which is favorable for the enhanced OER activity because of the easy adsorption of oxygen-containing intermediates and desorption of O^(2)in the OER process.In addition,the unique core-shell structure and robust bonding interface are responsible for the good stability for OER.This work provides fundamental insights on the bonding effect that determine the performance of OER electrocatalyst.
