Inverse design is an outstanding challenge in disordered systems with multiple length scales such as polymers, particularly when designing polymers with desired phase behavior. We demonstrate high-accuracy tuning of poly(2-oxazoline) cloud point via machine learning. With a design space of four repeating units and a range of molecular masses, we achieve an accuracy of 4°C root mean squared error (RMSE) in a temperature range of 24-90°C, employing gradient boosting with decision trees. The RMSE is >3x better than linear and polynomial regression. We perform inverse design via particle-swarm optimization, predicting and synthesizing 17 polymers with constrained design at 4 target cloud points from 37 to 80°C. Our approach challenges the status quo in polymer design with a machine learning algorithm, that is capable of fast and systematic discovery of new polymers.

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Lanthanum phosphate (LaP) nano-rods were synthesized using n-butylamine as a shape-directing agent (SDA). The resulting catalysts were applied in the dehydration of lactic acid to acrylic acid. Aiming to understand the nature of the active sites, the chemical and physical properties of LaP materials were studied using a variety of characterization techniques. This study showed that the SDA not only affected the porosity of the LaP materials but also modified the acid-base properties. Clearly, the modification of the acid-base properties played a more critical role in determining the catalytic performance than porosity. An optimized catalytic performance was obtained on the LaP catalyst with a higher concentration of Lewis acid sites. Basic sites showed negative effects on the stability of the catalysts. Good stability was achieved when the catalyst was prepared using the appropriate SDA/La ratio.

Polymeric hydrogels are promising biomaterials to be used as vitreous tamponade in the eye. However, while the clinical need and the required attributes of a vitreous replacement hydrogel are clear, there is a major gap in understanding the various polymer requirements to achieve the “ideal” hydrogel. In this study, we investigated the effect of the polymer molecular weight on polyurethane thermogel properties and found that there is a theoretical minimum number of hydrophobic blocks required for gelation. We then used these polymers as vitreous replacements. We found that there is a preferred molecular weight range, whereby hydrogels with lower molecular weights can cause retinal atrophy and corresponding functional visual loss, while those with higher molecular weights lead to opacity issues. Thermogels in the preferred molecular weight range retained the normal retinal structure and exhibited full visual recovery within 3 months. The effect of the molecular weight was further demonstrated by the effects of postsynthetic autoclaving on the retinal structure and function. The effect of the polymer molecular weight on the functional characteristics of hydrogels demonstrated herein is an important design parameter for polymeric hydrogels for ocular applications.

A “stop-flow” micro-tubing reactor system was designed for accelerating reaction discovery using flammable acetylene gas as the feedstock.

Plasmonic nanostructures have shown immense potential in photocatalysis because of their distinct photochemical properties associated with tunable photoresponses and strong light−matter interactions. The introduction of highly active sites is essential to fully exploit the potential of plasmonic nanostructures in photocatalysis, considering the inferior intrinsic activities of typical plasmonic metals. This review focuses on active site-engineered plasmonic nanostructures with enhanced photocatalytic performance, wherein the active sites are classified into four types (i.e., metallic sites, defect sites, ligand-grafted sites, and interface sites). The synergy between active sites and plasmonic nanostructures in photocatalysis is discussed in detail after briefly introducing the material synthesis and characterization methods. Active sites can promote the coupling of solar energy harvested by plasmonic metal to catalytic reactions in the form of local electromagnetic fields, hot carriers, and photothermal heating. Moreover, efficient energy coupling potentially regulates the reaction pathway by facilitating the excited state formation of reactants, changing the status of active sites, and creating additional active sites using photoexcited plasmonic metals. Afterward, the application of active site-engineered plasmonic nanostructures in emerging photocatalytic reactions is summarized. Finally, a summary and perspective of the existing challenges and future opportunities are presented. This review aims to deliver some insights into plasmonic photocatalysis from the perspective of active sites, expediting the discovery of high-performance plasmonic photocatalysts.

Materials that exhibit photothermal effect have attracted enormous research interests due to their ability to strongly absorb light and effectively transform it into heat for a wide range of applications...

Photothermal nanomaterials with a unique light-to-heat conversion property have great technological implications in a variety of areas ranging from biomedical to environmental applications. This book chapter summarizes the recent development of various light absorbing materials with photothermal effects into four functional categories, including plasmonic metals, semiconductors, carbon-, and polymer-based materials. The photothermal materials of these categories can be assembled and form hybrids or composites for enhanced photothermal performance. The different mechanisms of photothermal conversion as well as the potential applications in photothermal therapy, photothermal sterilization, and solar-driven water evaporation are discussed. Special attention is devoted to strategies that have been developed for improving the light absorption and light-to-heat conversion capabilities of these photothermal materials by tailoring the size, shape, composition, surface functionalities, bandgap, etc. Finally, the perspectives and challenges of the future development of photothermal materials are presented.