High-power UV-Laser Fragmentation System

作为一种基于分散的加工方法，激光破碎可以在没有分子稳定剂的情况下，在高度纯净的条件下合成几纳米大小的胶体无机纳米颗粒到原子团簇。申请人开发的连续液体射流工艺能够在稳态条件下进行材料加工，同时精确地量化能量输入。过去对氧化物破碎的研究表明，粒径减小后催化活性显著提高，但仍局限于一些小生境应用。特别是由于目前可用的高功率可见光/红外激光脉冲的低吸收率，氧化物的破碎仍然容易导致低质量吞吐量。相比之下，紫外激光脉冲对大多数纳米颗粒具有更大的吸收截面，因此可以实现更高的破碎效率和更多的材料变体研究。然而，椅子上可用的紫外激光器的激光功率不足（<20 W）已被发现是纳米颗粒加工的主要瓶颈，仍然限制了它们在科学研究中的应用。利用现有的设备，可以破碎尖晶石和钙钛矿、高熔点硬材料（如ZrB2、TiB2、TiC）或非等离子体贵金属（如Pt、Pd）和高熵合金（如Cantor合金），但数量非常少（mg的十分之一到百分之几）。基于将激光束源与最近开发的连续平面射流加工技术相结合进行的基础研究及其应用前景，包括功能测试所需的材料数量（例如，在多相催化或3D打印中），生产率和吞吐量的提高将为当前的研究创造巨大的增长潜力。这将对申请人的几个研究项目产生直接影响，包括协调项目，因为所要求的高性能紫外激光碎片系统已被发现占据关键位置，这对主席的研究光谱具有杠杆效应。前者的规格是根据基础和应用研究项目所需的材料和吞吐量来确定的。在这里，需要100克的高纯度胶体纳米颗粒。因此，不仅运行项目将受益于新的大型设备，而且在激光粉末床熔融（每批几公斤纳米功能化微粉末）和催化剂开发（每系列需要几克纳米催化剂）领域的新项目方法将成为可能。因此，应用连续操作的高性能紫外激光分散体加工技术将成为国际科学界的独特卖点。

As a dispersion-based processing method, laser fragmentation allows the synthesis of colloidal inorganic nanoparticles in the size range of a few nanometers up to atomic clusters under highly pure conditions without molecular stabilizers. The continuous liquid jet process developed by the applicant enables material processing under steady-state conditions while precisely quantifying the energy input. Past studies on the fragmentation of oxides show a significant increase of catalytic activity after size reduction but are still limited to some niche applications. Especially due to the low absorptivity of the currently available high-power VIS- / IR laser pulses, fragmentation of oxides is still prone to low mass throughput. In contrast, UV laser pulses show a significantly larger absorption cross-section for most nanoparticles consequently allowing a significantly higher fragmentation efficiency and more material-variant research. Yet, the insufficiently low laser power (<20 W) of the UV-lasers available at the chair has been found to poses a major bottleneck in nanoparticle processing still limiting their application in scientific studies. With the existing equipment, the fragmentation of e.g. spinels and perovskites, high-melting hard materials (e.g. ZrB2, TiB2, TiC), or non-plasmonic precious metals (eg Pt, Pd) and high entropy alloys (eg Cantor alloy) is found to be possible but only in very low quantities (several 10th – 100th of mg). Based on the fundamental research conducted by combining the laser beam source with recently developed continuous flat-jet processing technology and its application perspectives including the required material quantities for functional testing (e.g. in heterogenous Catalysis or in 3D printing) an increase in productivity and throughput will create tremendous growth potential for the present research. This will have a direct impact on several research projects of the applicant including coordinated programs since the requested high-performance UV-laser fragmentation system has been found to occupy a key position, which has a leverage effect on the research spectrum at the chair. The specifications of the former are defined based on the materials and throughputs required in basic and applied research projects. Here, high-purity colloidal nanoparticles are needed on a 100 g scale. Accordingly, not only running projects will benefit from the new large-scale equipment but also novel project approaches in the field of laser powder bed fusion (several kg of nano-functionalized micro powders per batch) and catalyst development (several grams of catalyst nanoparticles required per series) will be made possible. Consequently, the applied continuously operated high-performance UV-laser processing technology for dispersions will be a unique selling point in the international scientific community.