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Abstract Environmental Transmission Electron Microscopy gas holders are vital for studying catalyst nanostructures in reactive gases. Although there are existing methods to understand the behavior of catalysts during reaction, a “pressure gap” exists. Pressures of up to 4.5 bar have been demonstrated, but many industrial catalysts operate at 10–100 bar. This work introduces an ultra-high-pressure TEM gas holder designed to bridge this gap. Experiments demonstrate it can safely operate and achieve nanometer-scale resolution (~ 1.5 nm) in an Environmental TEM at pressures up to 27.5 bar. Practical resolution limitations are attributed to contamination and vibration rather than increased gas scatter. Graphical abstract 

Abstract Bicontinuous emulsion gels are mixtures with interpenetrating arrangements of two immiscible liquids stabilized with particles. The structures of such gels are readily made into simple macroscale geometries, like sheets and fibers; however, achieving more complex macroscopic structures while maintaining control over microscopic features and morphological bicontinuity remains a challenge. In this study, the ability to fabricate complex 3D structures of bicontinuous emulsion gels using direct ink writing (DIW) is demonstrated. The emulsion precursors are formulated with a mixture of hydrophilic and hydrophobic fumed silica particles; these precursors exhibit shear‐thinning and yield stress behavior necessary for DIW. The thixotropic nature of the precursor further promotes the formation of bicontinuous emulsion gels through vaporization‐induced phase separation and stabilization through both interfacial jamming and bulk stabilization mechanisms. This fabrication technique enables the creation of functional bicontinuous structures with complex architectures, paving the way for application in biomedical implants, catalytic reactors, and beyond. 

Abstract Double emulsions with core‐shell structures are versatile materials used in applications such as cell culture, drug delivery, and materials synthesis. A droplet library with precisely controlled dimensions and properties would streamline screening and optimization for specific applications. While microfluidic droplet generation offers high precision, it is typically labor‐intensive and sensitive to disturbances, requiring continuous operator intervention. To address these limitations, we present an artificial intelligence (AI)‐empowered automated double emulsion droplet library generator. This system integrates a convolutional neural network (CNN)‐based object detection model, decision‐making, and feedback control algorithms to automate droplet generation and collection. The system monitors droplet generation every 171 ms—faster than a Formula 1 driver's reaction time—ensuring rapid response to disturbances and consistent production of single‐core double emulsions. It autonomously generates libraries of 25 distinct monodisperse droplets with user‐defined properties. This automation reduces labor and waste, enhances precision, and supports rapid and reliable droplet library generation. We anticipate that this platform will accelerate discovery and optimization in biomedical, biological, and materials research. 

Abstract Granular hydrogels are emerging as an important class of scaffolds for biomedical applications, due to their injectability and pore structure to support cellular infiltration. Past research has primarily focused on spherical microgels, which allows limited control over granular hydrogel pore size and void volume fraction; however, investigation into microgels with higher aspect ratios has allowed even higher porosity. This study explores the impact of hyaluronic acid microgel aspect ratio (ranging from 3 to 5) on granular hydrogel porosity and cellular interactions. Both simulations and experimental results show increased void volume fractions and pore sizes in granular hydrogels formed from rod‐like microgels when compared to volume‐matched spherical microgels, which results in increased cellular invasion with an endothelial cell spheroid migration assay. Injection of the hydrogels into a confined space alters particle packing and void space, but porosity is still higher when rod‐like microgels are used, which results in increased cellular invasion when injected subcutaneously. Finally, the highest aspect ratio microgels are used as injectable granular hydrogels to treat myocardial infarction in rats and show reduced infarct area and enhanced functional outcomes when compared to untreated controls. This work provides further insight into microgel shape considerations for engineered granular hydrogels. 

Integrating Flory–Huggins theory into a Bayesian optimization workflow enhances the objectivity of mapping phase behavior in polymer blends. 

A phase change liquid infused surface that enables reversible solid and liquid lubricant state for microplastic localization. 

Nanoparticle diffusion in a polymer matrix is known to be sensitive to the surface chemistry and size of the nanoparticles, and this study explores the effect of grafted polymers on the nanoparticles. We report the diffusion coefficients of nanoparticles grafted with bottlebrush polymers in melts of linear polymers. These bottlebrush polymer-grafted nanoparticles (PGNs) are comprised of large silica NPs (radius 80 nm) grafted with various backbone degrees of polymerization and fixed polystyrene side chains (4.2 kDa) to give bottlebrush molecular weights of 80–388 kDa. The polymer matrix is polystyrene (100 or 425 kDa), and nanoparticle diffusion was studied at 170 °C. After annealing a trilayer sample, time-of-flight secondary ion mass spectrometry (ToF-SIMS) measured the cross-sectional PGN concentration profiles and extracted diffusion coefficients. The PGNs with high bottlebrush molecular weights relative to the matrix polymer display core–shell diffusion behavior, wherein the shell thickness is comparable to the grafted bottlebrush thickness. Surprisingly, when the bottlebrush molecular weight is smaller than the matrix polymer, the PGNs diffuse 10–100 times faster than predicted, which we attribute to a local decrease in viscosity associated with disentanglement of the matrix polymer near the large nanoparticles.