High-throughput Mechanochemistry Enabled by Resonant Acoustic Mixing

Abstract

This presentation introduces the Resonant Acoustic Mixing (RAM) technology as a revolutionary solution to traditional mechanochemistry drawbacks. RAM, a non-contact forced-vibrating mixing technology, is applied in a high-throughput mechanochemical application. Utilizing a specially designed 96-well plate holder, RAM facilitates rapid screening, optimization, and scope exploration in a Nickel-catalyzed amination cross-coupling reaction.

Comparative studies with traditional ball milling (BM) highlight RAM's superiority, minimizing the role of milling balls. Moreover, RAM's performance remains consistent in larger-scale reactions without additional optimizations, highlighting its potential for streamlined, environmentally friendly and large-scale industrial production.

Bio

Alice received her bachelor’s degree in Chemistry and Technologies for the Environment and Materials at the University of Bologna in Italy and master’s degree in Industrial Chemistry at the University of Bologna in Italy. In 2021, she joined as a Ph.D. student, Prof. Magnus Rueping’s group. Currently, her research focuses on developing transition metal-catalyzed solvent-free/near solvent-free reactions by mechanochemistry.

Coinage Metal Nanoclusters: Synthesis, Characterization, and Applications

 Abstract 

Ultrasmall Copper Nanoclusters (Cu NCs) have recently emerged as a new class of photocatalysts for organic synthesis, due to their exceptional light absorption ability, and large surface areas which provide efficient interactions with substrates. The precise structure of these nanomlecules offer a good opportunity to reveal the correlation between catalyst performance and structure at the atomic scale. Herein, we introduce the first copper NCs with a centered-Ino decahedra core, Cu19. The catalytic activity of Cu19 cluster were studied, and it exhibits excellent catalytic activity towards the synthesis of diaryl sulfones under mild conditions (blue LED, and room temperature). Cu₃₆Cl₂ and Cu₃₆Br₂ share the same exact structure, and both show two surface vacancy on their structure resulting from missing two copper atoms. The surface vacancy in Cu₃₆Cl₂ and Cu₃₆Br₂ act as an effective catalytic site. Au NCs exhibit outstanding intrinsic electronic and optical behaviors such as long carrier lifetime, and tunable photoluminescence quantum yield (PLQYs), and they are considered promising candidate materials for X-ray detection and imaging. Herein, we introduce Au4Cu4 NCs with PLQY=60%. To test scintillation materials, they need to be converted into films by mixing Au4Cu4 with a specific polymer, such as PMMA. Then they can be tested using indirect X-ray imaging systems. In addition, in our lab we are interested in the synthesis of other transition metals, such Ni and Co NCs. 

Bio 

Mohammed is currently in his third year of PhD under the supervision of Professor Osman Bakr at KAUST Catalysis Center. He obtained his MSc degree in Chemistry from Case Western Reserve University in 2020 under the supervision of Prof. Clemens Burda. His research focuses on the design and synthesis of metal nanoclusters and their applications.

Atomically Imaging Beam-Sensitive Porous Materials via 4D-STEM Ptychography

Abstract

Zeolites and metal-organic frameworks (MOFs) are two classes of porous materials extensively utilized across multiple domains, including gas adsorption and separation, catalysis, sensing, and biomedical applications. The rational design and comprehensive understanding of their properties necessitate detailed structural characterization. High-resolution transmission electron microscopy (TEM) offers crucial insights at atomic level, which is vital for structural analyses.

However, the significant sensitivity of these materials to electron beams poses a challenge for conventional TEM imaging techniques, as they often cause structural damage before achieving atomic-resolution images. Although current low-dose TEM methods, such as low-dose HRTEM and iDPC-STEM, have shown promise, they are not without their limitations.

This presentation will introduce 4D-STEM ptychography, including its imaging mechanisms and the advantages it offers over existing low-dose TEM methods. Successful applications in the study of porous materials will be discussed, with a focus on various zeolite samples and initial results on different MOFs. Additionally, the future directions for enhancing the capabilities of low-dose 4D-STEM ptychography in imaging extremely electron-beam-sensitive materials will be provided, highlighting its potential for broader application and impact in the field.

Bio

Guanxing Li is currently in pursuit of a Ph.D. degree at King Abdullah University of Science and Technology (KAUST), where he is conducting research under the supervision of Prof. Yu Han and co-advised by Prof. Zhiping Lai. Prior to this, he completed his Bachelor’s degree in 2018 at Wuhan University and his Master’s degree in 2021 at Zhejiang University in China. His research centers around the high-resolution characterization of electron-beam-sensitive nanocrystals employing low-dose TEM techniques, such as HRTEM, iDPC-STEM, and electron ptychography based on 4D-STEM.