Three-dimensional(3D)printed titanium alloy implants hold enormous potential in orthopedic applications to avoid stress shielding.However,titanium alloy is bioinert,limiting its application and making surface modifica...Three-dimensional(3D)printed titanium alloy implants hold enormous potential in orthopedic applications to avoid stress shielding.However,titanium alloy is bioinert,limiting its application and making surface modification a necessity.In this paper,porous implants were treated by acid etching and anodizing to improve the bioactivity,which was evaluated by simulated body fluid(SBF)immersion test.The results showed that,after surface modification,micro-nanocomposite structures were obtained on the titanium surface,and after immersing in SBF for 2 weeks,the implants showed a drastically enhanced apatite forming ability,confirming improved bioactivity.However,the surface structures were different at different positions and it is believed that this phenomenon is closely related to the different current densities of the surfaces during anodic oxidation.Our research evaluates the effect of anodic oxidation at different voltages on the surface modification and provides a reference for improving the bioactivity of the medical porous implant surface prepared by 3 D printing.展开更多
The widespread application of direct ethanol fuel cells is hampered due to the low activity,high cost and poor operation durability of electrocatalysts for ethanol oxidation reaction(EOR).Herein,we report a one-pot sy...The widespread application of direct ethanol fuel cells is hampered due to the low activity,high cost and poor operation durability of electrocatalysts for ethanol oxidation reaction(EOR).Herein,we report a one-pot synthetic method to synthesize PdPb3 nanochains with well-defined shape,size and composition via a solution-phase reduction method.The morphology,composition distribution and structure characteristics of PdPb3 nanochains were investigated by transmission electron microscopy,X-ray photoelectron spectroscopy and X-ray diffraction.Thanks to the unique structure,the as-obtained PdPb3 nanochains can manifest much higher mass activity(2523 mA·mg-1)and higher operation durability than commercial Pd/C(1272 mA·mg-1)during the EOR measurements.More importantly,further CO-stripping measurements indicate that the incorporation of Pb species could favor the oxidative removal of CO intermediates on the Pd electrode at the negative potential and enhance the EOR activity and stability,making it possible to develop highly active and durable electrocatalysts.展开更多
基金financially supported by the National Key Research and Development Program of China(No.2016YFB1101103)the National Natural Science Foundation of China(No.51771069)。
文摘Three-dimensional(3D)printed titanium alloy implants hold enormous potential in orthopedic applications to avoid stress shielding.However,titanium alloy is bioinert,limiting its application and making surface modification a necessity.In this paper,porous implants were treated by acid etching and anodizing to improve the bioactivity,which was evaluated by simulated body fluid(SBF)immersion test.The results showed that,after surface modification,micro-nanocomposite structures were obtained on the titanium surface,and after immersing in SBF for 2 weeks,the implants showed a drastically enhanced apatite forming ability,confirming improved bioactivity.However,the surface structures were different at different positions and it is believed that this phenomenon is closely related to the different current densities of the surfaces during anodic oxidation.Our research evaluates the effect of anodic oxidation at different voltages on the surface modification and provides a reference for improving the bioactivity of the medical porous implant surface prepared by 3 D printing.
基金financially supported by the National Natural Science Foundation of China(Nos.21673150,21703146 and 51802206)the Natural Science Foundation of Jiangsu Province(Nos.BK20180097 and BK20180846)+2 种基金the Program of the Ministry of Education of China for Introducing Talents of Discipline to Universities(111 Project)the Collaborative Innovation Center of Suzhou Nano Science and Technology(NANO-CIC)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)。
文摘The widespread application of direct ethanol fuel cells is hampered due to the low activity,high cost and poor operation durability of electrocatalysts for ethanol oxidation reaction(EOR).Herein,we report a one-pot synthetic method to synthesize PdPb3 nanochains with well-defined shape,size and composition via a solution-phase reduction method.The morphology,composition distribution and structure characteristics of PdPb3 nanochains were investigated by transmission electron microscopy,X-ray photoelectron spectroscopy and X-ray diffraction.Thanks to the unique structure,the as-obtained PdPb3 nanochains can manifest much higher mass activity(2523 mA·mg-1)and higher operation durability than commercial Pd/C(1272 mA·mg-1)during the EOR measurements.More importantly,further CO-stripping measurements indicate that the incorporation of Pb species could favor the oxidative removal of CO intermediates on the Pd electrode at the negative potential and enhance the EOR activity and stability,making it possible to develop highly active and durable electrocatalysts.
