Apatite coating with nanobelt structure was fabricated on single crystal silicon by a two-step method of electrodeposition at 1.0-2.0 mA/cm2 with DC power and vapor-thermal treatment(VTT) at 150-180℃ for 6 h over alk...Apatite coating with nanobelt structure was fabricated on single crystal silicon by a two-step method of electrodeposition at 1.0-2.0 mA/cm2 with DC power and vapor-thermal treatment(VTT) at 150-180℃ for 6 h over alkali medium.Scanning electron microscopy(SEM),X-ray diffractometry(XRD),and electron diffraction spectrometry(EDS) were employed to investigate the compositions and morphologies of specimens before or after vapor-thermal treatment.The results demonstrate that nanobelt crystals of coating,0.5-2 μm in width,100 nm in thickness,and 6-10 μm in length,are Ca-deficient apatite(CDA) with a mole ratio of Ca to P approximately of 1.60,which shows similarity of the nanobelt coating to inorganic phase in composition and to collagen in dimension appearing in human hard tissue.Induced nucleation and growth of bone-like apatite were observed on the nanobelt after soaking in a simulated body fluid(SBF) for 6 h and for 3 d,respectively,identifying that nanobelt has good ability for induction of bone-like apatite in SBF.展开更多
Oxygen defects play a critical role in the electrocatalytic oxygen evolution reaction(OER).Therefore,in-depth understanding the structure-activity-mechanism relationship of these defects is the key to design efficient...Oxygen defects play a critical role in the electrocatalytic oxygen evolution reaction(OER).Therefore,in-depth understanding the structure-activity-mechanism relationship of these defects is the key to design efficient OER electrocatalysts.This relationship needs to be understood dynamically due to the potential for irreversible phase transitions during OER.Consequently,significant efforts have been devoted to study the dynamic evolution of oxygen defects to shed light on the OER mechanism.This review critically examines and analyzes the dynamic processes occurring at oxygen defect sites during OER,including defect formation and defect evolution mechanisms,along with the advanced characterization techniques needed to understand these processes.This review aims to provide a comprehensive understanding of high-efficiency electrocatalysts,with a particular emphasis on the importance of in situ monitoring the dynamic evolution of oxygen defects,providing a new perspective towards efficient OER electrocatalyst design.展开更多
基金Project(50702020) supported by the National Natural Science Foundation of China
文摘Apatite coating with nanobelt structure was fabricated on single crystal silicon by a two-step method of electrodeposition at 1.0-2.0 mA/cm2 with DC power and vapor-thermal treatment(VTT) at 150-180℃ for 6 h over alkali medium.Scanning electron microscopy(SEM),X-ray diffractometry(XRD),and electron diffraction spectrometry(EDS) were employed to investigate the compositions and morphologies of specimens before or after vapor-thermal treatment.The results demonstrate that nanobelt crystals of coating,0.5-2 μm in width,100 nm in thickness,and 6-10 μm in length,are Ca-deficient apatite(CDA) with a mole ratio of Ca to P approximately of 1.60,which shows similarity of the nanobelt coating to inorganic phase in composition and to collagen in dimension appearing in human hard tissue.Induced nucleation and growth of bone-like apatite were observed on the nanobelt after soaking in a simulated body fluid(SBF) for 6 h and for 3 d,respectively,identifying that nanobelt has good ability for induction of bone-like apatite in SBF.
基金supported by the Ministry of Science and Technology(MOST)of China through the Key Project of Research&Development(2021YFF0500502)。
文摘Oxygen defects play a critical role in the electrocatalytic oxygen evolution reaction(OER).Therefore,in-depth understanding the structure-activity-mechanism relationship of these defects is the key to design efficient OER electrocatalysts.This relationship needs to be understood dynamically due to the potential for irreversible phase transitions during OER.Consequently,significant efforts have been devoted to study the dynamic evolution of oxygen defects to shed light on the OER mechanism.This review critically examines and analyzes the dynamic processes occurring at oxygen defect sites during OER,including defect formation and defect evolution mechanisms,along with the advanced characterization techniques needed to understand these processes.This review aims to provide a comprehensive understanding of high-efficiency electrocatalysts,with a particular emphasis on the importance of in situ monitoring the dynamic evolution of oxygen defects,providing a new perspective towards efficient OER electrocatalyst design.
