Pulsed Laser System for Nanoparticle Production and Processing

液体中脉冲激光烧蚀和液体中脉冲激光碎裂的方法能够在高纯度条件下生产和加工胶体纳米颗粒。由于纳米粒子固有的高比表面积，表面纯度对于区分表面功能和表面吸附效应非常重要。高表面纯度是脉冲激光系统生产纳米颗粒的一大优势，这也是近年来这些基于激光的方法日益成为研究热点的原因。而脉冲激光在液体中的烧蚀已广泛应用于各种材料。在表面等离子体（即可见波长激光脉冲）的共振激发下，主要对金纳米颗粒等模型金属材料进行了脉冲激光破碎研究。由于现有高功率激光器对VIS/IR激光脉冲的低吸收，用于增材制造或摩擦学的氧化物纳米颗粒的进一步研究在吞吐量和粒度上受到严重限制。相比之下，紫外激光脉冲的吸收截面要大得多（特别是对半导体、氧化物和大多数金属纳米粒子）。因此，通过使用紫外激光器，可以更有效地研究激光烧蚀和碎裂。使用我们小组现有的红外激光器，只有在数量不足的框架下才能破碎，例如氧化物（例如，Y2O3, ZrO2），高熔点硬材料（例如，ZrB2, TiB2, TiC）或高熵合金（例如，Cantor-Alloy）。由于应用前景和功能测试（例如增材制造）的数量要求，吞吐量的显着增加具有相当大的研究潜力。激光生产和加工的材料应用于申请人的多个研究项目，包括协调项目。因此，提议的高功率紫外激光系统在新任命的材料科学和增材制造主席的研究光谱中占据了关键地位，发挥了杠杆作用。同时，它将强化型材核心“Materials.Inspire”。伍珀塔尔大学的系统。该主要仪器的规格是根据与基础和应用研究项目相关的材料和必要的吞吐量来定义的。这需要高纯度的胶体纳米粒子，部分规模为100克。因此，主持会议的一系列正在进行的项目将受益于这项新文书。此外，在激光粉末床融合领域的进一步项目方法（每批几公斤纳米添加微粉）将变得可行。该分散体的连续操作高性能紫外激光生产和加工技术可以与拟议的设备一起实施，将在国际上代表一个显着的特征。

The methods of pulsed laser ablation in liquids and pulsed laser fragmentation in liquids enable the production and processing of colloidal nanoparticles under high-purity conditions. Due to the inherent high specific surface area of nanoparticles, surface purity is of great importance for the discrimination of surface functionality from surface adsorbate effects. The high surface purity is one of the great strengths of nanoparticle production by pulsed laser systems, which is why these laser-based methods have increasingly become the focus of research in recent years. While pulsed laser ablation in liquids has been applied to a broad range of materials. Investigation of pulsed laser fragmentation has been carried out mainly on model metal materials such as gold nanoparticles under resonant excitation of the surface plasmons (i.e., laser pulses in the visible wavelength). Further studies on oxide nanoparticles employed for additive manufacturing or tribology are severely limited in throughput and particle size due to the low absorption of VIS/IR laser pulses employed in existing high-power lasers. UV- laser pulses, in contrast, show a much larger absorption cross-section (especially for semiconductors, oxides, and most metal nanoparticles). Consequently, by using UV-lasers, a much more efficient and material-variant research of laser ablation and fragmentation is possible. With the existing IR-lasers in our group, fragmentation of, e.g., oxides (e.g., Y2O3, ZrO2), high melting hard materials (e.g., ZrB2, TiB2, TiC) or high entropy alloys (e.g., Cantor-Alloy) is only possible in insufficient quantity frameworks. The significant increase in throughput has considerable research potential due to the application perspective and the quantity requirement for functional testing (e.g., in additive manufacturing). The laser-produced and processed materials are applied in several research projects of the applicant, including coordinated programs. The proposed high-power UV laser system thus occupies a key position that exerts a leverage effect on the research spectrum at the newly appointed Chair of Materials Science and Additive Manufacturing. Meanwhile, it will strengthen the profile core “Materials.Inspire.Systems” of the University of Wuppertal. The specifications of this major instrumentation are defined based on materials and necessary throughputs relevant to basic and applied research projects. These require high-purity colloidal nanoparticles partly on a scale of 100 g. Accordingly, a whole series of ongoing projects at the Chair will benefit from the new instrument. In addition, further project approaches in the field of laser powder bed fusion (several kg of nanoadditivated micropowder per batch) will become feasible. The continuously operated high-performance UV laser production and processing technology for dispersions that can be implemented with the proposed equipment will represent a distinguishing feature internationally.