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Zr掺杂TiO_(2)纳米粒子的合成及光催化性能研究 被引量:4
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作者 任庆云 王松涛 +1 位作者 李汶静 范荫恒 《功能材料》 CAS CSCD 北大核心 2021年第11期11164-11168,共5页
采用溶胶-凝胶法制备了不同含量Zr掺杂的纳米TiO_(2)粉体,通过XRD、SEM、UV-Vis、PL和光催化性能分析等对Zr掺杂TiO_(2)纳米粒子的各项性能进行了表征。结果表明,所有含量Zr掺杂的TiO_(2)纳米粒子的结构均为锐钛矿型,且衍射峰型较尖锐,... 采用溶胶-凝胶法制备了不同含量Zr掺杂的纳米TiO_(2)粉体,通过XRD、SEM、UV-Vis、PL和光催化性能分析等对Zr掺杂TiO_(2)纳米粒子的各项性能进行了表征。结果表明,所有含量Zr掺杂的TiO_(2)纳米粒子的结构均为锐钛矿型,且衍射峰型较尖锐,无其他杂质峰出现,其纯度和结晶度均较高;分析晶胞参数发现,Zr成功地掺杂进入了TiO_(2)的晶格;未掺杂Zr的TiO_(2)纳米粒子颗粒分布不均匀,且尺寸大小偏差较大;掺入少量的Zr后,颗粒分散度得到了轻微改善,颗粒呈现出较为规则的球型,表面粗糙度稍有增加,当Zr含量为3%(质量分数)时,改善效果最佳;当Zr含量为5%(质量分数)时,过量的Zr会附着在TiO_(2)表面,从而导致其光滑性和分散性变差、表面活性降低;掺入不同含量Zr后的TiO_(2)纳米粒子的吸收边带均出现了轻微的红移现象,使得TiO_(2)纳米粒子对光的吸收能力增强,在可见光下的光催化性能得到提高;Zr的掺入使TiO_(2)纳米粒子的光生电子和空穴的复合得到了明显减弱,这有助于TiO_(2)纳米粒子光催化性能的提高;未掺杂Zr的TiO_(2)纳米粒子的降解效率在120 min时为12.3%,当Zr的含量为3%(质量分数)时,TiO_(2)纳米粒子的降解效率最高为87.3%,但Zr掺量较多时,光催化性能反而出现了轻微下降,由此可见,Zr的最佳掺量为3%(质量分数)。 展开更多
关键词 Zr掺杂 TiO_(2)纳米粒子 微观形貌 红移现象 光催化性能
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A Fundamentally Irreversible World as an Opportunity towards a Consistent Understanding of Quantum and Cosmological Contexts
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作者 Helmut Tributsch 《Journal of Modern Physics》 2016年第12期1455-1482,共29页
In a preceding publication a fundamentally oriented and irreversible world was shown to be derivable from the important principle of least action. A consequence of such a paradigm change is avoidance of paradoxes with... In a preceding publication a fundamentally oriented and irreversible world was shown to be derivable from the important principle of least action. A consequence of such a paradigm change is avoidance of paradoxes within a “dynamic” quantum physics. This becomes essentially possible because fundamental irreversibility allows consideration of the “entropy” concept in elementary processes. For this reason, and for a compensation of entropy in the spread out energy of the wave, the duality of particle and wave has to be mediated via an information self-image of matter. In this publication considerations are extended to irreversible thermodynamics, to gravitation and cosmology with its dependence on quantum interpretations. The information self-image of matter around particles could be identified with gravitation. Because information can also impose an always constant light velocity there is no need any more to attribute such a property to empty space, as done in relativity theory. In addition, the possibility is recognized to consider entropy generation by expanding photon fields in the universe. Via a continuous activation of information on matter photons can generate entropy and release small energy packages without interacting with matter. This facilitates a new interpretation of galactic redshift, emphasizes an information link between quantum- and cosmological phenomena, and evidences an information-triggered origin of the universe. Self-organized processes approach maximum entropy production within their constraints. In a far from equilibrium world also information, with its energy content, can self-organize to a higher hierarchy of computation. It is here identified with consciousness. This appears to explain evolution of spirit and intelligence on a materialistic basis. Also gravitation, here identified as information on matter, could, under special conditions, self-organize to act as a super-gravitation, offering an alternative to dark matter. Time is not an illusion, but has to be understood as flux of action, which is the ultimate reality of change. The concept of an irreversible physical world opens a route towards a rational understanding of complex contexts in nature. 展开更多
关键词 Fundamental Irreversibility Gravitation as Information redshift as Entropy phenomenon Constancy of Light Velocity Time Information Driven Universe
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First-principles calculation of Aun@(ZnS)(42)(n=6-16)hetero-nanostructure system
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作者 Han-Yue Zhao Qing Liu +4 位作者 Xiao-Xu Wang Jin-Rong Huo Lu Li Ping Qian Yan-Jing Su 《Rare Metals》 SCIE EI CAS CSCD 2020年第10期1165-1173,共9页
The structure stability and electronic and optical properties of a series of Au@ZnS core-shell nanocomposites with different sizes were investigated theoretically by first-principle calculation based on density functi... The structure stability and electronic and optical properties of a series of Au@ZnS core-shell nanocomposites with different sizes were investigated theoretically by first-principle calculation based on density functional theory(DFT).A series of Aun@(ZnS)(42)structures with different n values from 6 to 16 were optimized and obtained.Based on the core-shell interaction energy and second-order difference of total energy of these structures,it is found that Au(13)@(ZnS)(42)turns out to be the most stable structure.Based on the model of Au(13)@(ZnS)(42),the density of state and charge density difference were studied and provided a deeper understanding of the electronic structures of Au@ZnS.On the other hand,absorption coefficient and dielectric function were investigated to study the optical properties.It is found that an optical absorption peak appears in visible-light region,indicating that the photo-catalytic can be improved prominently due to the optical redshift to visible-light region when forming core-shell structure from ZnS bulk.And the redshift phenomenon accords well with experiment.Furthermore,the electronic structure further confirms the existence of redshift of optical absorption spectrum. 展开更多
关键词 Core-shell structure Density functional theory(DFT) Electronic structure Optical properties redshift phenomenon
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