Establishing the synthesis/structure relationship of molybdenum/lead chalcogenide quantum dot mesocrystals

建立钼/铅硫族化物量子点介晶的合成/结构关系

• 批准号: 2206122
• 负责人: Tobias Hanrath
• 金额: $ 18万
• 依托单位: Cornell University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-06-15 至 2024-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2206122&HistoricalAwards=false
• 关键词: Establishing; synthesis; structure; relationship; molybdenum

Non-technical summaryWith this project, supported by the Solid State and Materials Chemistry program in the Division of Materials Research, Professor Tobias Hanrath at Cornell University will explore the synthesis-structure relationships of a novel class of materials that combines nanoparticles with two-dimensional (2D) materials. By analogy to the rock-paper-scissors game, the investigators will use colloidal nanoparticles (i.e., rocks) to template the formation of molybdenum sulfide sheets (i.e., paper) on specific sections of the nanoparticle. Instead of scissors, the proposed synthesis approach leverages the well-defined nanoparticle shape (e.g., truncated cubes) to define the geometry of the particle-sheet composite. This project will have significant broader impact beyond the creation of new knowledge of scientific and societal importance, potentially leading to the development of new nanostructured composite materials with unique optical, electronic, and catalytic properties. Graduate students will receive extensive training and experience at the confluence of material fabrication and characterization approaches to investigate, understand and predict the formation of composite nanostructures. Outreach and education are closely integrated with the scientific work. The investigators will develop a ‘back-to-the-future’ workshop to engage participants by developing their vision for the future of their specific research field, the broader technological implications, and their personal roles and opportunities in bringing this future to fruition. Technical Summary The overarching objective of the proposed project, supported by the Solid State and Materials Chemistry program in the Division of Materials Research, is to establish the foundational synthesis/structure relationship of molybdenum/lead chalcogenide quantum dot mesocrystals. Mesocrystals are defined as assemblies of smaller constituent crystals arranged with high degree of translational and orientational ordering in their superlattice sites. Access to colloidal quantum dot (QD) building blocks with precisely defined size, shape, and composition as well as concurrent progress in understanding of and control over directed assembly and attachment have enabled remarkable advances in QD mesocrystals. Currently available QD mesocrystals are limited to single composition structures, yet the scientific and technological evolution of isolated QDs has taught us that moving from single-components to multi-composition heterostructures (e.g., core-shell or Janus-like) introduces advanced and programmable functionalities. The PI has identified the synthesis and analysis of heterostructured QD mesocrystals as a scientifically interesting and technologically important research challenge. The PI embraces the challenge of establishing processing/structure relationships as an opportunity to closely integrate synthesis, assembly, and materials characterization. The proposal presents a hypothesis-driven approach with three complementary objectives focused on formation of facet-specific PbX-(MoS2)m misfit layer heterostructures, and directed assembly of isolated PbX-(MoS2)m into a new class of superstructures. The proposed research presents an exciting opportunity to significantly improve upon the knowledge of QD mesocrystals with properties by design. The goals of the proposed research are ambitious, and the generated knowledge will significantly advance basic understanding, design, predictability and control over heterostructured QD mesocrystals with compelling far-reaching prospects for future advances in electrocatalysis and optoelectronicsThis award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

非技术性总结通过该项目，由材料研究部的固态和材料化学计划支持，康奈尔大学的Tobias Hanrath教授将探索一类新型材料的合成-结构关系，该材料将纳米颗粒与二维（2D）材料相结合。通过类比石头剪刀布游戏，研究人员将使用胶体纳米粒子（即，岩石）以模板形成硫化钼片（即，纸）在纳米颗粒的特定部分上。代替剪刀，所提出的合成方法利用了明确定义的纳米颗粒形状（例如，截顶立方体）以限定颗粒-片复合物的几何形状。该项目将产生更广泛的影响，超越创造具有科学和社会重要性的新知识，可能导致开发具有独特光学，电子和催化性能的新型纳米结构复合材料。研究生将在材料制造和表征方法的汇合处接受广泛的培训和经验，以调查，理解和预测复合纳米结构的形成。外联和教育与科学工作密切结合。研究人员将开发一个“回到未来”的研讨会，通过发展他们对特定研究领域未来的愿景，更广泛的技术影响以及他们在实现这一未来方面的个人角色和机会来吸引参与者。该项目由材料研究部的固态和材料化学项目支持，其总体目标是建立钼/铅硫属化物量子点介晶的基础合成/结构关系。介晶被定义为在其超晶格位置以高度平移和取向有序排列的较小组成晶体的集合体。获得具有精确定义的尺寸、形状和组成的胶体量子点（QD）构建块以及在理解和控制定向组装和附着方面的同时进展使得QD介晶取得了显着进展。目前可用的QD介晶限于单组分结构，然而分离的QD的科学和技术发展已经教导我们，从单组分到多组分异质结构（例如，核-壳或Janus类）引入了高级和可编程的功能。PI已经将异质结构QD介晶的合成和分析确定为科学上有趣且技术上重要的研究挑战。PI接受建立加工/结构关系的挑战，将其作为将合成、组装和材料表征紧密结合的机会。该提案提出了一种假设驱动的方法，具有三个互补的目标，重点是形成特定于面的PbX-（MoS 2）m失配层异质结构，并将孤立的PbX-（MoS 2）m定向组装成一类新的超结构。拟议的研究提出了一个令人兴奋的机会，显着提高量子点介晶的知识与设计的性能。拟议研究的目标是雄心勃勃的，所产生的知识将显着推进对异质结构量子点介晶的基本理解，设计，可预测性和控制，对电催化和光电子学的未来发展具有引人注目的深远前景。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估来支持。