基于相平衡主导的气液固生长机理设计制备氮化物和硫化物一维纳米新材料

Design and controllable synthesis of nanomaterials is a long-term dream in nanoscience and nanotechnology, which depends on the deep insight into the growth mechanism. The applicant had carried out a quantitative experimental study on the growth of AlN nanowires by nitriding Al69Ni31 alloy particles across 1133-1638 ℃ during the doctoral program, disclosed the phase-equilibrium-dominated origin of the growth process, further understood the phase-equilibrium-dominated vapor-liquid-solid (PED-VLS) growth mechanism. The project would adopt this mechanism as a direction, precisely predict and design novel one-dimensional (1D) nitride and sulfide nanomaterials according to their corresponding phase diagrams, for example, the design growth of Si3N4 and GaN nanowires by nitriding Fe-Si and Fe-Ga alloys, etc., of ZnS and SnSx nanowires by sulfiding Ag-Zn and Ag-Sn alloys, etc.. The evolution process and intrinsic mechanism for the growth of nanowires would be quantitatively studied using the modern analysis techniques such as the X-ray diffraction, electron microscopy and thermal analysis. This project could clarify the general validity of the PED-VLS growth mechanism and specify its applicability, obtain several novel 1D nanomaterials, promote the evolution from empirical science to rational prediction and design in nanomaterials synthesis, and advance the systematic development of 1D nanomaterials research.

纳米材料的设计和可控制备是纳米科学和技术领域的长期梦想，该目标的实现有赖于对生长机理的深刻理解。申请人攻读博士期间，通过定量化实验研究了在1133-1638 ℃温区内氮化Al69Ni31合金生长AlN纳米线的过程，揭示了该生长过程本质上受相平衡主导，深化了对相平衡主导的气液固生长机理的认识。本项目拟以该机理为指导，根据相图精确预测和设计制备氮化物和硫化物一维纳米新材料，例如，通过氮化Fe-Si、Fe-Ga等合金设计制备Si3N4、GaN等氮化物纳米线，硫化Ag-Zn、Ag-Sn等合金设计制备ZnS、SnSx等硫化物纳米线。采用X射线衍射、电子显微镜、热分析等现代分析手段定量研究纳米线生长的演变历程和规律。通过本项目研究，能够明确相平衡主导的气液固生长机理的普适性，并界定其适用条件，获得多个新型的一维纳米材料，推进纳米材料的制备从经验科学走向理性预测和设计，促进一维纳米材料研究的系统化进程。

纳米材料的设计和可控制备是纳米科学和技术领域的长期梦想，该目标的实现有赖于对生长机理的深刻理解。通过氮化Fe-Si合金制备Si3N4纳米线体系对相平衡主导的气液固生长机理的适用条件有了深入认识；然后拓展至硫化Ag-Zn等合金体系，制备得到了[Ag-Zn合金][ZnS]等ZnS基异质结构，深化了对相平衡主导的气液固生长机理的普适性认识；进一步利用相平衡的原理，采用Ag2S纳米颗粒与Ag-Zn等合金反应，成功制备了新型的多元异质结纳米结构，如Ag-[Zn-S]异质结纳米结构；再是，借鉴气液固生长机理制备新材料的经验，基于与气液固生长类似的溶液固固生长，设计制备了一系列新型的多元异质结纳米材料，如Ag2S-Zn1-xMnxS、Cu2-xS-ZnS、Cu2-xS-Co1-xS等；此外，通过结合溶液固固生长和表面外延生长，构建了复杂的纳米线异质结构，如Zn1-xMnxS@ZnS。采用X射线衍射、电子显微镜、热分析等现代分析手段研究了纳米材料生长的历程和演变规律。本研究结果进一步明确了相平衡主导的气液固生长机理的普适性，获得了制备一系列新型的多元异质结纳米材料的技术路线，推进了纳米材料的制备从经验科学走向理性预测和设计，促进了一维纳米材料研究的系统化进程。