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Electron beam-induced polymerization (EBIP) has been widely explored in coatings, adhesives, and nanostructure fabrication, relying on electron irradiation to generate reactive species that initiate polymerization via radical pathways [1]. While its efficiency in solid and thin-film systems is well established [2], real-time observation of gas-phase polymerization at the nanoscale remains challenging due to the lack of suitable experimental platforms. In this study, we employ a custom-built ultrathin (UT) membrane gas-cell chip for in-situ closed-cell environmental transmission electron microscopy (ETEM). This platform offers enhanced reciprocal and spectral visibility, enabling precise tracking of crystallinity through diffraction patterns and gas composition through electron energy loss spectroscopy (EELS) [3-5]. By allowing real-time observation of polymerization kinetics under controlled electron irradiation, this work aims to elucidate the fundamental mechanisms governing EBIP in the gas phase, addressing a critical knowledge gap in electron beam-driven chemical reactions. 

2D nanomaterials have garnered significant attention due to their unique physicochemical properties. MXene, a type of twodimensional transition metal carbide, nitride, or carbonitride, has become a focal point in materials science due to its excellent metallic conductivity, tunable chemical functional groups, outstanding mechanical properties, and unique surface chemistry [1,2]. Compared to traditional metal oxides, MXenes exhibit superior mechanical strength and flexibility, making them ideal candidates for high-performance energy storage devices (such as lithium-ion batteries and supercapacitors) as well as flexible electronic devices [3]. However, there are still some limitations, such as the self-stacking phenomenon, which restricts the improvement of its performance. Researchers have gradually expanded various types of MXene structures, enhancing their value in fields such as energy, electronics, sensing, nanofluids, computing, and the environment by tuning the element composition, surface functional groups, interlayer structure, and composite structure design [4,5]. 

Polycrystalline ion conductors are widely used as solid electrolytes in energy storage technologies. However, they often exhibit poor ion transport across grain boundaries and pores. This work demonstrates that strategically tuning the mesoscale microstructures, including pore size, pore distribution, and chemical compositions of grain boundaries, can improve ion transport. Using LiTa₂PO₈as a case study, we have shown that the combination of LiF as a sintering agent with Hf⁴⁺implantation improves grain-grain contact, resulting in smaller, evenly distributed pores, reduced chemical contrast, and minimized nonconductive impurities. A suite of techniques has been used to decouple the effects of LiF and Hf⁴⁺. Specifically, LiF modifies particle shape and breaks large pores into smaller ones, while Hf⁴⁺addresses the chemical mismatches between grains and grain boundaries. Consequently, this approach achieves nearly two orders of magnitude improvement in ion conduction. Tuning mesoscale structures offers a cost-effective method for enhancing ion transport in polycrystalline systems and has notable implications for synthesizing high-performance ionic materials. 

Environmental transmission electron microscopy (E-TEM) enables direct observation of nanoscale chemical processes crucial for catalysis and materials design. However, the high-energy electron probe can dramatically alter reaction pathways through radiolysis, the dissociation of molecules under electron beam irradiation. While extensively studied in liquid-cell TEM, the impact of radiolysis in gas phase reactions remains unexplored. Here, we present a numerical model elucidating radiation chemistry in both gas and liquid E-TEM environments. Our findings reveal that while gas phase E-TEM generates radiolytic species with lower reactivity than liquid phase systems, these species can accumulate to reaction-altering concentrations, particularly at elevated pressures. We validate our model through two case studies: the radiation-promoted oxidation of aluminum nanocubes and disproportionation of carbon monoxide. In both cases, increasing the electron beam dose rate directly accelerates their reaction kinetics, as demonstrated by enhanced AlOx growth and carbon deposition. Based on these insights, we establish practical guidelines for controlling radiolysis in closed-cell nanoreactors. This work not only resolves a fundamental challenge in electron microscopy but also advances our ability to rationally design materials with subÅngstrom resolution. 

Understanding chromatin organization requires integrating measurements of genome connectivity and physical structure. It is well established that cohesin is essential for TAD and loop connectivity features in Hi-C, but the corresponding change in physical structure has not been studied using electron microscopy. Pairing chromatin scanning transmission electron tomography with multiomic analysis and single-molecule localization microscopy, we study the role of cohesin in regulating the conformationally defined chromatin nanoscopic packing domains. Our results indicate that packing domains are not physical manifestation of TADs. Using electron microscopy, we found that only 20% of packing domains are lost upon RAD21 depletion. The effect of RAD21 depletion is restricted to small, poorly packed (nascent) packing domains. In addition, we present evidence that cohesin-mediated loop extrusion generates nascent domains that undergo maturation through nucleosome posttranslational modifications. Our results demonstrate that a 3D genomic structure, composed of packing domains, is generated through cohesin activity and nucleosome modifications. 

Abstract Graphite is a commonly used raw material across many industries and the demand for high‐quality graphite has been increasing in recent years, especially as a primary component for lithium‐ion batteries. However, graphite production is currently limited by production shortages, uneven geographical distribution, and significant environmental impacts incurred from conventional processing. Here, an efficient method of synthesizing biomass‐derived graphite from biochar is presented as a sustainable alternative to natural and synthetic graphite. The resulting bio‐graphite equals or exceeds quantitative quality metrics of spheroidized natural graphite, achieving a RamanI_D/I_Gratio of 0.051 and crystallite size parallel to the graphene layers (L_a) of 2.08 µm. This bio‐graphite is directly applied as a raw input to liquid‐phase exfoliation of graphene for the scalable production of conductive inks. The spin‐coated films from the bio‐graphene ink exhibit the highest conductivity among all biomass‐derived graphene or carbon materials, reaching 3.58 ± 0.16 × 10⁴S m⁻¹. Life cycle assessment demonstrates that this bio‐graphite requires less fossil fuel and produces reduced greenhouse gas emissions compared to incumbent methods for natural, synthesized, and other bio‐derived graphitic materials. This work thus offers a sustainable, locally adaptable solution for producing state‐of‐the‐art graphite that is suitable for bio‐graphene and other high‐value products.