The reduction in noble metal content for efficient oxygen evolution catalysis is a crucial aspect towards the large scale commercialisation of polymer electrolyte membrane electrolyzers.Since catalytic stability and a...The reduction in noble metal content for efficient oxygen evolution catalysis is a crucial aspect towards the large scale commercialisation of polymer electrolyte membrane electrolyzers.Since catalytic stability and activity are inversely related,long service lifetime still demands large amounts of low-abundant and expensive iridium.In this manuscript we elaborate on the concept of maximizing the utilisation of iridium for the oxygen evolution reaction.By combining different tin oxide based support materials with liquid atomic layer deposition of iridium oxide,new possibilities are opened up to grow thin layers of iridium oxide with tuneable noble metal amounts.In-situ,time-and potential-resolved dissolution experiments reveal how the stability of the substrate and the catalyst layer thickness directly affect the activity and stability of deposited iridium oxide.Based on our results,we elaborate on strategies how to obtain stable and active catalysts with maximized iridium utilisation for the oxygen evolution reaction and demonstrate how the activity and durability can be tailored correspondingly.Our results highlight the potential of utilizing thin noble metal films with earth abundant support.materials for future catalytic applications in the energy sector.展开更多
Carbon-protected magnetic nanoparticles exhibit long-term stability in acid or alkaline medium, good biocompatibility, and high saturation magnetization. As a result, they hold great promise for magnetic resonance ima...Carbon-protected magnetic nanoparticles exhibit long-term stability in acid or alkaline medium, good biocompatibility, and high saturation magnetization. As a result, they hold great promise for magnetic resonance imaging, photothermal therapy, etc. However, since pyrolysis, which is often required to convert the carbon precursors to carbon, typically leads to coalescence of the nanoparticles, the obtained carbon-protected magnetic nanoparticles are usually sintered as a non-dispersible aggregation. We have successfully synthesized discrete, dispersible, and uniform carbon-protected magnetic nanoparticles via a precise surface/interface nano-engineering approach. Remarkably, the nanoparticles possess excellent water-dispersibility, biocompatibility, a high T2 relaxivity coefficient （384 mM^-1·s^-1）, and a high photothermal heating effect. Furthermore, they can be used as multifunctional core components suited for future extended investigation in early diagnosis, detection and therapy, catalysis, separation, and magnetism.展开更多
文摘The reduction in noble metal content for efficient oxygen evolution catalysis is a crucial aspect towards the large scale commercialisation of polymer electrolyte membrane electrolyzers.Since catalytic stability and activity are inversely related,long service lifetime still demands large amounts of low-abundant and expensive iridium.In this manuscript we elaborate on the concept of maximizing the utilisation of iridium for the oxygen evolution reaction.By combining different tin oxide based support materials with liquid atomic layer deposition of iridium oxide,new possibilities are opened up to grow thin layers of iridium oxide with tuneable noble metal amounts.In-situ,time-and potential-resolved dissolution experiments reveal how the stability of the substrate and the catalyst layer thickness directly affect the activity and stability of deposited iridium oxide.Based on our results,we elaborate on strategies how to obtain stable and active catalysts with maximized iridium utilisation for the oxygen evolution reaction and demonstrate how the activity and durability can be tailored correspondingly.Our results highlight the potential of utilizing thin noble metal films with earth abundant support.materials for future catalytic applications in the energy sector.
基金Acknowledgements This project was financially supported by National Natural Science Foundation of China （No. 21225312）. We appreciate Dr. Fang Fang at Wuhan Institute of Physics and Mathematics of China for assistance with the in vitro MRI measurement, Dr. Liming Wang at National Center for Nanoscience and Technology of China for assistance with the cell experiments.
文摘Carbon-protected magnetic nanoparticles exhibit long-term stability in acid or alkaline medium, good biocompatibility, and high saturation magnetization. As a result, they hold great promise for magnetic resonance imaging, photothermal therapy, etc. However, since pyrolysis, which is often required to convert the carbon precursors to carbon, typically leads to coalescence of the nanoparticles, the obtained carbon-protected magnetic nanoparticles are usually sintered as a non-dispersible aggregation. We have successfully synthesized discrete, dispersible, and uniform carbon-protected magnetic nanoparticles via a precise surface/interface nano-engineering approach. Remarkably, the nanoparticles possess excellent water-dispersibility, biocompatibility, a high T2 relaxivity coefficient （384 mM^-1·s^-1）, and a high photothermal heating effect. Furthermore, they can be used as multifunctional core components suited for future extended investigation in early diagnosis, detection and therapy, catalysis, separation, and magnetism.
