Herein is reported the soft-templating synthesis of visible-light photoactive bismuth ferrite （BiFeO3） nanoarchitectures in the form of thin fihns using a poly（ethylene-co-butylene）-block-poly（ethylene oxide） di...Herein is reported the soft-templating synthesis of visible-light photoactive bismuth ferrite （BiFeO3） nanoarchitectures in the form of thin fihns using a poly（ethylene-co-butylene）-block-poly（ethylene oxide） diblock copolymer as the structure-directing agent. We establish that （1） the self-assembled materials employed in this work are highly crystalline after annealing at 550 ℃ in air and that （2） neither the bismuth-poor Bi2Fe4O9 phase nor other impurity phases are formed. We further show that there is a distinct restructuring of the high quality cubic pore network of amorphous BiFeO3 during crystallization. This restructuring leads to films with a unique architecture that is composed of anisotropic crystallites intermingled with a continuous mesoporosity. While this article focuses on the characterization of these novel materials by electron microscopy, krypton physisorption, grazing incidence small-angle X-ray scattering, time-of-flight secondary ion mass spectrometry, X-ray photoelectron spectroscopy, UV-vis and Raman spectroscopy, we also examine the photocatalytic properties and show the benefits of the combination of mesoporosity and nanocrystallinity. Templated BiFeO3 thin films （25% porosity） with a direct optical band gap at 2.9 eV exhibit a catalytic activity for the degradation of rhodamine B much better than that of nontemplated samples. We attribute this improvement to the nanoscale porosity, which provides for more available active sites on the photocatalyst.展开更多
飞行时间二次离子质谱仪(Time of flight secondary ion mass spectrometry,TOF-SIMS)对所有元素具有极高的检测灵敏度,应用此方法研究了经550℃退火处理,Au/AuBe/Au与GaP金属-半导体的各元素强度分布特性,依次分析金属表面、金属层内...飞行时间二次离子质谱仪(Time of flight secondary ion mass spectrometry,TOF-SIMS)对所有元素具有极高的检测灵敏度,应用此方法研究了经550℃退火处理,Au/AuBe/Au与GaP金属-半导体的各元素强度分布特性,依次分析金属表面、金属层内、金属-半导体界面、半导体内部,使用O2+正离子与Cs+负离子分析Au、Be、O、Ga、P五类元素在各层内的强度,观察金属层与半导体界面内Be、O、Au、P峰位置的各元素SIMS图,表明在金属表面3~10nm内含有Au、Be、O、Ga、P元素,在金属内部,O元素在AuBe层有明显分布,在半导体材料GaP层内含有Be、Au元素,且Be的扩散深度比Au要深,在AuBe层及界面处用XPS分析化学组分。展开更多
对InSb红外探测器钝化前清洗工艺进行了研究。在传统清洗方法的基础上增加专用清洗液进行清洗,以优化钝化前InSb材料的表面质量。飞行时间二次离子质谱仪(Time-of-Flight Secondary Ion Mass Spectrometry,TOF-SIMS)质谱检测表明,增加...对InSb红外探测器钝化前清洗工艺进行了研究。在传统清洗方法的基础上增加专用清洗液进行清洗,以优化钝化前InSb材料的表面质量。飞行时间二次离子质谱仪(Time-of-Flight Secondary Ion Mass Spectrometry,TOF-SIMS)质谱检测表明,增加专用清洗液清洗工艺后,InSb材料表面的Si杂质浓度降低了约85%,主要有机物杂质浓度降幅约为30%~60%,表面整体杂质含量显著降低。经流片验证,增加专用清洗液进行钝化前表面清洗,I-V性能更优,InSb光伏芯片的长期可靠性显著提高。这说明钝化前InSb材料的表面质量对InSb红外探测器的性能和可靠性具有重要影响。本文提供的钝化前清洗优化方向具有一定的指导意义。展开更多
文摘Herein is reported the soft-templating synthesis of visible-light photoactive bismuth ferrite （BiFeO3） nanoarchitectures in the form of thin fihns using a poly（ethylene-co-butylene）-block-poly（ethylene oxide） diblock copolymer as the structure-directing agent. We establish that （1） the self-assembled materials employed in this work are highly crystalline after annealing at 550 ℃ in air and that （2） neither the bismuth-poor Bi2Fe4O9 phase nor other impurity phases are formed. We further show that there is a distinct restructuring of the high quality cubic pore network of amorphous BiFeO3 during crystallization. This restructuring leads to films with a unique architecture that is composed of anisotropic crystallites intermingled with a continuous mesoporosity. While this article focuses on the characterization of these novel materials by electron microscopy, krypton physisorption, grazing incidence small-angle X-ray scattering, time-of-flight secondary ion mass spectrometry, X-ray photoelectron spectroscopy, UV-vis and Raman spectroscopy, we also examine the photocatalytic properties and show the benefits of the combination of mesoporosity and nanocrystallinity. Templated BiFeO3 thin films （25% porosity） with a direct optical band gap at 2.9 eV exhibit a catalytic activity for the degradation of rhodamine B much better than that of nontemplated samples. We attribute this improvement to the nanoscale porosity, which provides for more available active sites on the photocatalyst.
文摘飞行时间二次离子质谱仪(Time of flight secondary ion mass spectrometry,TOF-SIMS)对所有元素具有极高的检测灵敏度,应用此方法研究了经550℃退火处理,Au/AuBe/Au与GaP金属-半导体的各元素强度分布特性,依次分析金属表面、金属层内、金属-半导体界面、半导体内部,使用O2+正离子与Cs+负离子分析Au、Be、O、Ga、P五类元素在各层内的强度,观察金属层与半导体界面内Be、O、Au、P峰位置的各元素SIMS图,表明在金属表面3~10nm内含有Au、Be、O、Ga、P元素,在金属内部,O元素在AuBe层有明显分布,在半导体材料GaP层内含有Be、Au元素,且Be的扩散深度比Au要深,在AuBe层及界面处用XPS分析化学组分。
文摘对InSb红外探测器钝化前清洗工艺进行了研究。在传统清洗方法的基础上增加专用清洗液进行清洗,以优化钝化前InSb材料的表面质量。飞行时间二次离子质谱仪(Time-of-Flight Secondary Ion Mass Spectrometry,TOF-SIMS)质谱检测表明,增加专用清洗液清洗工艺后,InSb材料表面的Si杂质浓度降低了约85%,主要有机物杂质浓度降幅约为30%~60%,表面整体杂质含量显著降低。经流片验证,增加专用清洗液进行钝化前表面清洗,I-V性能更优,InSb光伏芯片的长期可靠性显著提高。这说明钝化前InSb材料的表面质量对InSb红外探测器的性能和可靠性具有重要影响。本文提供的钝化前清洗优化方向具有一定的指导意义。
