本文主要研究内容
作者李博（2019）在《不同环境条件对CdSe/ZnS量子点荧光特性的影响规律》一文中研究指出：半导体量子点具有能级分立、尺寸可调等很多优异特性,在LED、高效太阳能电池、生物荧光探针以及传感器等领域都有广泛应用,其光电特性一直是国际上的研究热点。然而,在实际应用中,量子点器件难免会遇到强电/磁场、高/低温、高压等外界环境条件,进而对其性能产生影响。因此,研究外界环境条件对量子点荧光特性的影响具有重要的实际应用价值。目前存在的问题是,关于外界环境条件对半导体量子点荧光特性影响规律的研究尚需进一步完善。比如,电化学环境下的表面电子注入/离子吸附对荧光特性的影响机制、高温条件下的荧光淬灭机制、高压条件下量子点之间的相互作用、高光子能量激发条件对荧光量子效率的影响机制等。本文以CdSe/ZnS核/壳结构量子点作为研究对象,通过对其吸收光谱、稳态荧光谱、时间分辨荧光光谱的分析,研究了不同环境条件对量子点荧光特性的影响规律。研究了电化学环境对CdSe/ZnS量子点荧光特性的影响规律。对稳态荧光光谱和时间分辨荧光光谱进行了同步分析,发现量子点本征态发光和表面态发光在不同的电极电位下呈现不同的变化规律:前者随负电极电位的升高出现红移,后者则随着负电极电位的升高而逐渐呈现蓝移。研究表明,红移是由于阳离子的吸附导致量子限域效应减弱,蓝移是由于表面态电子的注入导致较高能级表面态发光的几率增加。此外,本征态发光和表面态发光的荧光强度都随负电极电位的升高而显著降低,这是由于空间电荷导致的激子非辐射复合过程的影响。研究了高低温环境对CdSe/ZnS量子点荧光特性的影响规律。对稳态和时间分辨荧光光谱的进行分析,研究表明,在80-500 K的温度范围内,可逆荧光淬灭的根本来源为空穴的热逃逸。而在320 K-500 K的高温区域,荧光还有额外的不可逆淬灭途径,这是由于在加热过程中生成了新的表面缺陷态,导致表面俘获,从而引起深陷阱能级发光以及非辐射复合过程。此外,在80-500 K的温度范围内,随着温度升高,荧光峰位红移,光谱增宽,峰位红移是由于量子点体材料带隙随温度升高而收缩,光谱增宽是由于激子和声学/光学声子的耦合作用。研究了高压环境对CdSe/ZnS量子点荧光特性的影响规律。对稳态荧光和时间分辨荧光光谱的研究结果表明,随着压力升高,荧光发射波长逐渐蓝移,但在高压区域,荧光发射波长的蓝移率降低。一方面是由于材料的弹性模量随压力逐渐增加,导致晶格被压缩的速率减慢,因此蓝移率降低;另一方面是由于高压下量子点之间的相互作用,导致发射波长红移,从而使蓝移率降低。此外,在高压区域,量子点间相互作用还使量子点中电子空穴波函数的交叠变小,导致荧光寿命变长。研究了激发光子能量对CdSe/ZnS量子点荧光特性的影响规律。综合分析吸收、荧光和激发谱等实验数据,得出相对荧光量子效率随激发光子能量升高而降低的变化规律。综合实验数据和唯象模型的理论模拟,研究表明,荧光量子效率减小的程度取决于热电子的表面俘获和弛豫的竞争关系。较高的激发态上热电子俘获速率增加,导致参与辐射复合的激子减少,从而荧光量子效率降低。另外,微观模型的理论模拟表明,表面陷阱深度对荧光量子效率有很大的影响,陷阱越深,电子的俘获速率越大,去俘获速率越小,荧光量子效率的减小越显著。本论文系统研究了不同外界环境条件对CdSe/ZnS量子点体系荧光特性的影响规律,为探索量子点中激子动力学过程的物理机制提供了新思路,有助于解决量子点器件在实际应用环境中存在的问题。
Abstract
ban dao ti liang zi dian ju you neng ji fen li 、che cun ke diao deng hen duo you yi te xing ,zai LED、gao xiao tai yang neng dian chi 、sheng wu ying guang tan zhen yi ji chuan gan qi deng ling yu dou you an fan ying yong ,ji guang dian te xing yi zhi shi guo ji shang de yan jiu re dian 。ran er ,zai shi ji ying yong zhong ,liang zi dian qi jian nan mian hui yu dao jiang dian /ci chang 、gao /di wen 、gao ya deng wai jie huan jing tiao jian ,jin er dui ji xing neng chan sheng ying xiang 。yin ci ,yan jiu wai jie huan jing tiao jian dui liang zi dian ying guang te xing de ying xiang ju you chong yao de shi ji ying yong jia zhi 。mu qian cun zai de wen ti shi ,guan yu wai jie huan jing tiao jian dui ban dao ti liang zi dian ying guang te xing ying xiang gui lv de yan jiu shang xu jin yi bu wan shan 。bi ru ,dian hua xue huan jing xia de biao mian dian zi zhu ru /li zi xi fu dui ying guang te xing de ying xiang ji zhi 、gao wen tiao jian xia de ying guang cui mie ji zhi 、gao ya tiao jian xia liang zi dian zhi jian de xiang hu zuo yong 、gao guang zi neng liang ji fa tiao jian dui ying guang liang zi xiao lv de ying xiang ji zhi deng 。ben wen yi CdSe/ZnShe /ke jie gou liang zi dian zuo wei yan jiu dui xiang ,tong guo dui ji xi shou guang pu 、wen tai ying guang pu 、shi jian fen bian ying guang guang pu de fen xi ,yan jiu le bu tong huan jing tiao jian dui liang zi dian ying guang te xing de ying xiang gui lv 。yan jiu le dian hua xue huan jing dui CdSe/ZnSliang zi dian ying guang te xing de ying xiang gui lv 。dui wen tai ying guang guang pu he shi jian fen bian ying guang guang pu jin hang le tong bu fen xi ,fa xian liang zi dian ben zheng tai fa guang he biao mian tai fa guang zai bu tong de dian ji dian wei xia cheng xian bu tong de bian hua gui lv :qian zhe sui fu dian ji dian wei de sheng gao chu xian gong yi ,hou zhe ze sui zhao fu dian ji dian wei de sheng gao er zhu jian cheng xian lan yi 。yan jiu biao ming ,gong yi shi you yu yang li zi de xi fu dao zhi liang zi xian yu xiao ying jian ruo ,lan yi shi you yu biao mian tai dian zi de zhu ru dao zhi jiao gao neng ji biao mian tai fa guang de ji lv zeng jia 。ci wai ,ben zheng tai fa guang he biao mian tai fa guang de ying guang jiang du dou sui fu dian ji dian wei de sheng gao er xian zhe jiang di ,zhe shi you yu kong jian dian he dao zhi de ji zi fei fu she fu ge guo cheng de ying xiang 。yan jiu le gao di wen huan jing dui CdSe/ZnSliang zi dian ying guang te xing de ying xiang gui lv 。dui wen tai he shi jian fen bian ying guang guang pu de jin hang fen xi ,yan jiu biao ming ,zai 80-500 Kde wen du fan wei nei ,ke ni ying guang cui mie de gen ben lai yuan wei kong xue de re tao yi 。er zai 320 K-500 Kde gao wen ou yu ,ying guang hai you e wai de bu ke ni cui mie tu jing ,zhe shi you yu zai jia re guo cheng zhong sheng cheng le xin de biao mian que xian tai ,dao zhi biao mian fu huo ,cong er yin qi shen xian jing neng ji fa guang yi ji fei fu she fu ge guo cheng 。ci wai ,zai 80-500 Kde wen du fan wei nei ,sui zhao wen du sheng gao ,ying guang feng wei gong yi ,guang pu zeng kuan ,feng wei gong yi shi you yu liang zi dian ti cai liao dai xi sui wen du sheng gao er shou su ,guang pu zeng kuan shi you yu ji zi he sheng xue /guang xue sheng zi de ou ge zuo yong 。yan jiu le gao ya huan jing dui CdSe/ZnSliang zi dian ying guang te xing de ying xiang gui lv 。dui wen tai ying guang he shi jian fen bian ying guang guang pu de yan jiu jie guo biao ming ,sui zhao ya li sheng gao ,ying guang fa she bo chang zhu jian lan yi ,dan zai gao ya ou yu ,ying guang fa she bo chang de lan yi lv jiang di 。yi fang mian shi you yu cai liao de dan xing mo liang sui ya li zhu jian zeng jia ,dao zhi jing ge bei ya su de su lv jian man ,yin ci lan yi lv jiang di ;ling yi fang mian shi you yu gao ya xia liang zi dian zhi jian de xiang hu zuo yong ,dao zhi fa she bo chang gong yi ,cong er shi lan yi lv jiang di 。ci wai ,zai gao ya ou yu ,liang zi dian jian xiang hu zuo yong hai shi liang zi dian zhong dian zi kong xue bo han shu de jiao die bian xiao ,dao zhi ying guang shou ming bian chang 。yan jiu le ji fa guang zi neng liang dui CdSe/ZnSliang zi dian ying guang te xing de ying xiang gui lv 。zeng ge fen xi xi shou 、ying guang he ji fa pu deng shi yan shu ju ,de chu xiang dui ying guang liang zi xiao lv sui ji fa guang zi neng liang sheng gao er jiang di de bian hua gui lv 。zeng ge shi yan shu ju he wei xiang mo xing de li lun mo ni ,yan jiu biao ming ,ying guang liang zi xiao lv jian xiao de cheng du qu jue yu re dian zi de biao mian fu huo he chi yu de jing zheng guan ji 。jiao gao de ji fa tai shang re dian zi fu huo su lv zeng jia ,dao zhi can yu fu she fu ge de ji zi jian shao ,cong er ying guang liang zi xiao lv jiang di 。ling wai ,wei guan mo xing de li lun mo ni biao ming ,biao mian xian jing shen du dui ying guang liang zi xiao lv you hen da de ying xiang ,xian jing yue shen ,dian zi de fu huo su lv yue da ,qu fu huo su lv yue xiao ,ying guang liang zi xiao lv de jian xiao yue xian zhe 。ben lun wen ji tong yan jiu le bu tong wai jie huan jing tiao jian dui CdSe/ZnSliang zi dian ti ji ying guang te xing de ying xiang gui lv ,wei tan suo liang zi dian zhong ji zi dong li xue guo cheng de wu li ji zhi di gong le xin sai lu ,you zhu yu jie jue liang zi dian qi jian zai shi ji ying yong huan jing zhong cun zai de wen ti 。
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论文作者分别是来自哈尔滨工业大学的李博，发表于刊物哈尔滨工业大学2019-12-07论文，是一篇关于量子点论文,荧光特性论文,电化学论文,温度和压力论文,激发光子能量论文,哈尔滨工业大学2019-12-07论文的文章。本文可供学术参考使用，各位学者可以免费参考阅读下载，文章观点不代表本站观点，资料来自哈尔滨工业大学2019-12-07论文网站，若本站收录的文献无意侵犯了您的著作版权，请联系我们删除。
标签：量子点论文; 荧光特性论文; 电化学论文; 温度和压力论文; 激发光子能量论文; 哈尔滨工业大学2019-12-07论文;