Photoexcited Electrons Driven by Doping Concentration Gradient: Flux-Prepared NaTaO3 Photocatalysts Doped with Strontium Cations
Photoexcited Electrons Driven by Doping Concentration Gradient: Flux-Prepared NaTaO3 Photocatalysts Doped with Strontium Cations
复制标题
DOI：
10.1021/acscatal.8b02437
复制
发表时间：
2018-08
期刊：
影响因子：
12.9
通讯作者：
Longjie An;M. Kitta;Akihide Iwase;A. Kudo;N. Ichikuni;H. Onishi
中科院分区：
文献类型：
--
作者：
Longjie An;M. Kitta;Akihide Iwase;A. Kudo;N. Ichikuni;H. Onishi
电子-空穴复合总是与半导体光催化剂上所需的反应竞争。降低复合概率对于提高反应的量子效率至关重要。先前的研究表明，掺杂镧系元素或碱土金属阳离子可降低用于人工光合作用的 NaTaO3 光催化剂的复合概率。这项研究背后的动机是揭示客体金属阳离子如何降低重组概率。 NaTaO3 光催化剂通过在熔融 NaCl 熔剂中结晶而掺杂 Sr 阳离子，产生 50-100 nm 大小的 NaTaO3-Sr(Sr1/3Ta2/3)O3 固溶体颗粒。 Sr 阳离子的颗粒内分布对热熔剂中的浸泡时间敏感，其中相对于 Ta 的固定 Sr 浓度为 2 mol%。延长浸泡 60 小时可得到均匀的 Sr 分布。缩短浸泡时间 1 小时，产生覆盖有 3 nm 厚的 Sr 累积层的颗粒。带隙激发电子的数量...
Electron–hole recombination always competes with desired reactions on semiconductor photocatalysts. Reducing recombination probability is essential for increasing the quantum efficiency of the reactions. Previous studies demonstrated that doping with lanthanoid or alkaline-earth metal cations reduced recombination probability in NaTaO3 photocatalysts for artificial photosynthesis. The motivation behind this study was to reveal how the guest metal cations reduced recombination probability. NaTaO3 photocatalysts were doped with Sr cations through crystallization in molten NaCl flux to produce 50–100 nm sized particles of NaTaO3–Sr(Sr1/3Ta2/3)O3 solid solution. Intraparticle distribution of Sr cations was sensitive to immersion time in the hot flux with a fixed Sr concentration of 2 mol % relative to Ta. Extended immersion for 60 h resulted in a homogeneous Sr distribution. Curtailed immersion for 1 h yielded particles capped with a 3 nm thick Sr-accumulated layer. The population of electrons bandgap-excited...