%0 Journal Article
%T 六面体形Ta<sub>2</sub>O<sub>5</sub>@Ta<sub>3</sub>N<sub>5</sub>的熔盐辅助高温氮化控制合成及可见光解水析氢性能<br>Controlled Synthesis of Hexahedron Ta<sub>2</sub>O<sub>5</sub>@Ta<sub>3</sub>N<sub>5</sub> by Molten-Salt-Assisted High-Temperature Nitridation and the Performance for Hydrogen Evolution from Water-Splitting by Visible Light
%A 张京
%J Material Sciences
%P 485-496
%@ 2160-7621
%D 2021
%I Hans Publishing
%R 10.12677/MS.2021.114056
%X 利用混合熔盐辅助高温氮化成功制备了六面体形Ta<sub>2</sub>O<sub>5</sub>@Ta<sub>3</sub>N<sub>5</sub>光催化剂。调控助熔剂种类、混合熔盐配比、Ta<sub>2</sub>O<sub>5</sub>与混合熔盐比例等工艺条件，制备出六面体形Ta<sub>2</sub>O<sub>5</sub>，确定最佳制备条件为NaCl和Na<sub>2</sub>CO<sub>3</sub>混合熔盐(摩尔比为1:1)作为助熔剂，Ta<sub>2</sub>O<sub>5</sub>和混合熔盐比例为1:3 (质量比)，再经过800℃氮化处理3 h，仍保持六面体拓扑结构，建立了分步控制合成工艺。以水热合成的无规则形貌Ta<sub>2</sub>O<sub>5</sub>为前驱体，利用混合熔盐辅助技术，经800℃氮化4 h制备出核壳异质结构的六面体形Ta<sub>2</sub>O<sub>5</sub>@Ta<sub>3</sub>N<sub>5</sub>，建立了晶面控制与异质结构建同步控制合成工艺；其光电流密度达到0.57 μA？cm<sup>？2</sup>，是前者(0.28 μA？cm<sup>？2</sup>)的2.03倍，比课题组前期制备的无规则形貌Ta<sub>2</sub>O<sub>5</sub>@Ta<sub>3</sub>N<sub>5</sub>提高了一个数量级，产氢活性为(709 μmol？g<sup>？1</sup>？h<sup>？1</sup>)，也远远高于无规则形貌Ta<sub>2</sub>O<sub>5</sub>@Ta<sub>3</sub>N<sub>5</sub> (21.75 μmol？g<sup>？1</sup>？h<sup>？1</sup>)。六面体形貌的棱角改变体相电荷分布，以及Ta<sub>3</sub>N<sub>5</sub>/Ta<sub>2</sub>O<sub>5</sub>异质结构的构筑有效促进了光生电子空穴分离，提升了载流子分离效率，为进一步实现表面空间选择性修饰助催化剂奠定了实验基础。<br />
Hexahedral Ta<sub>2</sub>O<sub>5</sub>@Ta<sub>3</sub>N<sub>5</sub> photocatalyst was successfully prepared by high temperature nitriding assisted by mixed molten salt. Hexahedral Ta<sub>2</sub>O<sub>5</sub> was prepared by adjusting the flux type, the ratio of mixed molten salt and the ratio of Ta<sub>2</sub>O<sub>5</sub> to mixed molten salt and other technological conditions. The optimal preparation conditions were as follows: NaCl and Na<sub>2</sub>CO<sub>3</sub> mixed molten salt (molar ratio: 1:1) as flux, and the ratio of Ta<sub>2</sub>O<sub>5</sub> to mixed molten salt was 1:3 (mass ratio). After being nitridated at 800？C for 3 h, the hexahedral topological structure was still maintained. A step-by-step controlled synthesis process was established. Using the irregular morphology of Ta<sub>2</sub>O<sub>5</sub> synthesized by hydrothermal method as precursor, the hexahedron Ta<sub>2</sub>O<sub>5</sub>@Ta<sub>3</sub>N<sub>5</sub> with core-shell heterostructure was prepared by nitridation at 800？C for 4 h using mixed molten salt assisted technology. The synthesis process of crystal plane control and heterostructure construction was established. The photocurrent density reached 0.57 μA？cm<sup>？2</sup>, which was 2.03 times that of the former (0.28 μA？cm<sup>？2</sup>), and was an order of magnitude higher than that of the previous irregular morphologies Ta<sub>2</sub>O<sub>5</sub>@Ta<sub>3</sub>N<sub>5</sub>. The activity of hydrogen production was 709 μmol？g<sup>？1</sup>？h<sup>？1</sup>, which was much higher than that of the irregular morphology (21.75 μmol？g<sup>？1</sup>？h<sup>？1</sup>). The edges and angles of the hexahedral morphology change the volume
%K 六面体，Ta<sub>2</sub>O<sub>5</sub>@Ta<sub>3</sub>N<sub>5</sub>，异质结，光催化，析氢<br>Hexahedral
%K Ta<sub>2</sub>O<sub>5</sub>@Ta<sub>3</sub>N<sub>5</sub>
%K Heterojunction
%K Photocatalysis
%K Hydrogen Evolution
%U http://www.hanspub.org/journal/PaperInformation.aspx?PaperID=42027