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Developing highly efficient non-iridium-based active sites for acidic water splitting is still a huge challenge. Herein, unique Ru–B–Cr moieties have been constructed in RuO2nanofibers (NFs) to activate Ru sites for water electrolysis, which overcomes the bottleneck of RuO2-based catalysts usually possessing low activity for the hydrogen evolution reaction (HER) and poor stability for the oxygen evolution reaction (OER). The fabricated Cr, B-doped RuO2NFs exhibit low overpotentials of 205 and 379 mV for acidic HER and OER at 1 A cm–2with outstanding stability lasting 1000 and 188 h, respectively. The assembled acidic electrolyzer also possesses great hydrogen production efficiency and durability at a high current density. Experimental and theoretical explorations reveal that the formation of Ru–B–Cr moieties effectively optimizes the atomic configurations and modulates the adsorption/desorption free energy of reaction intermediates to achieve exceptional HER and OER performance.

This study presents a highly efficient Surface Mechanical Treatment (SMT) inspired by metal forging principles developed to significantly enhance the mechanical properties and surface durability of engineering plastics, including PA66, PEEK, POM, and PPS. Offering a sustainable and energy-efficient alternative to conventional polymer processing techniques, SMT achieves remarkable property enhancements. For example, when applied to PA66, SMT improved Young’s Modulus by 88.39% and Ultimate Tensile Strength (UTS) by 28.37%, while the surface layer demonstrated a 10-fold increase in modulus to approximately 10 GPa, accompanied by a 43.29% rise in Vickers Hardness and a 10% improvement in crystallinity. The methodology combines the application of compressive and shear forces via a custom-designed device with advanced molecular dynamics simulations, including force field molecular dynamics (FFMD) and ab initio molecular dynamics (AIMD). These simulations revealed a unique “chain-combing” mechanism, aligning polymer chains and reinforcing hydrogen bonding at the molecular level. Comprehensive structural analyses, such as SAXS and WAXS, further confirmed these findings by demonstrating enhanced crystallinity and the development of a pronounced surface-to-bulk property gradient. This research underscores the transformative potential of SMT as a surface-specific modification strategy, enabling substantial macroscopic property improvements through localized molecular restructuring. The findings open new avenues for processing engineering plastics, offering a pathway to developing more durable and efficient materials for industrial applications.

The deposition/stripping behavior of lithium metal is intriguing, and the associated formation of inactive lithium at various temperatures remains elusive, which hinders the practical application of lithium metal batteries. Here, utilizing the variable-temperature operando solid-state nuclear magnetic resonance (SS NMR) technique, we reveal the temperature effects on the lithium microstructure evolution in a carbonate-based electrolyte system. In addition, the mass spectrometry titration (MST) method is used to quantify the evolution of inactive lithium components, including dead lithium, solid electrolyte interface (SEI), and lithium hydride (LiH). Combined SS NMR and MST results show that the morphology of lithium metal is reasonably correlated to the amount of inactive Li formed. At low/ambient temperature, the lithium microstructure has a similar evolution pattern, and its poor morphology leads to a large amount of dead lithium, which dominates capacity loss; however, at high temperature large and dense lithium deposits form with less dead Li detected, and the intensified electrolyte consumption in SEI formation is the major cause for capacity loss. Our phase-field simulation results reveal that the compact lithium deposition formed at higher temperature is due to the more uniformly distributed electric field and Li+concentration. Lastly, two strategies in forming a dense Li deposit are proposed and tested that show performance-enhancing results.

Olefin selectivity and catalyst lifetime are two key metrics for industrial methanol-to-olefin catalysts. Currently, it is very difficult to obtain high olefin selectivity and long catalyst lifetime at the same time. Herein, a feasible strategy combining precoking and steaming to directionally construct the active naphthalenic species within the crystal center of the SAPO-34 catalyst has been developed, which can not only promote the lower olefin selectivity to ∼89% (ethylene and propylene) but also prolong the catalyst lifetime by ∼3.7-fold in the methanol-to-olefin conversion. Structured illumination microscopy, in situultraviolet–visible spectroscopy, and online mass spectrometry elucidate the spatiotemporal distribution and evolution of the naphthalenic species during the precoking and steaming processes. This one-stone-two-birds strategy is applicable to a commercial SAPO-34 catalyst containing a binder, demonstrating its bright prospect in the methanol-to-olefin industry.

Seed-assisted low alkalinity gel system was developed to explore the organic-free synthesis of MOR zeolite. MOR nanoassemblies with Si/Al ratio (SAR) up to 9.4 and high solid yield (84–94%) were successfully obtained under controlled low alkalinity conditions. Characterization results demonstrate that the acid strength increases in parallel with the SAR, while the total acid amount and the proton distribution in the main channels and the side pockets are similar for the samples. The proton distribution in the H-MOR is not straightforwardly related to the Na+distribution in the as-synthesized MOR, implying the transfer of the protons among the oxygen sites of framework T atom. Relative to low-silica samples I-5.3 and I-7.4, sample I-9.4 displays the best mass transfer performance and accessibility of the acid sites by pyridine due to its relatively low Al density and mild dealumination degree. Correspondingly, sample I-9.4 (pyridine-modified catalyst) shows the best activity with ca.100% selectivity of methyl acetate (MAc) in the DME carbonylation reaction. The high steady MAc yield (6.8 mmol/g/h) over sample I-9.4 suggests the promising application of MOR nanoassemblies synthesized by this economical organic-free strategy

Zeolites, the most technically important crystalline microporous materials, are indispensable cornerstones of chemical engineering because of their remarkable catalytic properties and adsorption capabilities. Numerous studies have demonstrated that the hierarchical engineering of zeolites can maximize accessible active sites and improve mass transport, which significantly decreases the internal diffusion limits to achieve the desired performance. However, the construction of hierarchical zeolites with ordered alignments and size-controlled substructures in a convenient way is highly challenging. Herein, we develop a facile procedure using two common structure-directing agents, tetrapropylammonium hydroxide (TPAOH) and tetraethylammonium hydroxide (TEAOH), to synthesize hierarchically aligned ZSM-5 (Hie-ZSM-5) crystals with a-axis alignment substructures of controllable size. The control of the substructure size (α) in the range of 10–60 nm and the corresponding similarity (r= α/β, where β is the size of Hie-ZSM-5) ranging from 0.004 to 0.033 can be tuned by varying the Si/Al ratios (40–120). A systematic investigation of the overall crystallization process, using time-dependent XRD, SEM, TEM, and solid-state magic-angle spinning NMR (13C, 27Al, 29Si) methods, enable us to construct a solid mechanism for the generation of Hie-ZSM-5. Most importantly, directional transport in the unique structures of Hie-ZSM-5 efficiently enhances mass diffusion, as well as catalytic activity and stability. These findings improve our understanding of the zeolite crystallization process and inspire novel methods for the rational design of hierarchical zeolites.

Temperature is a critical parameter in chemical conversion, significantly affecting the reaction kinetics and thermodynamics. Measuring temperature inside catalyst particles of industrial interest (∼micrometers to millimeters), which is crucial for understanding the evolution of chemical dynamics at catalytic active sites during reaction and advancing catalyst designs, however, remains a big challenge. Here, we propose an approach combining two-photon confocal microscopy and state-of-the-art upconversion luminescence (UL) imaging to measure the spatiotemporal-resolved temperature within individual catalyst particles in the industrially significant methanol-to-hydrocarbons reaction. Specifically, catalyst particles containing zeolites and functional nanothermometers were fabricated using microfluidic chips. Our experimental results directly demonstrate that the zeolite density and particle size can alter the temperature distribution within a single catalyst particle. Importantly, the observed temperature heterogeneity plays a decisive role in the activation of the reaction intermediate and the utilization of active sites. We expect that this work opens a venue for unveiling the reaction mechanism and kinetics within industrial catalyst particles by considering temperature heterogeneity.

DNL-6, a silicoaluminophosphate (SAPO) molecular sieve with RHO topology, was hydrothermally synthesized using a new structure-directing agent (SDA), N,N′-dimethylethylenediamine. The obtained samples were characterized by X-ray diffraction, X-ray fluorescence, X-ray photoelectron spectroscopy, scanning electron microscopy, and N2adsorption, which indicated that the synthesized DNL-6s have high crystallinity and relatively high Si content ranging from 20% to 35%. Solid-state magic-angle-spinning (MAS) nuclear magnetic resonance (13C, 29Si, 27Al, 31P, and 27Al multiple-quantum (MQ)) was conducted to investigate the status of the SDA and local atomic environment in the as-synthesized DNL-6. Thermal analysis revealed the presence of a large amount of amines in the DNL-6 crystals (about 4.4 SDAs per α-cage), which was the reason for the formation of DNL-6 with an ultrahigh Si content (36.4% Si per mole). Interestingly, DNL-6 exhibited excellent catalytic performance for methanol amination. More than 88% methanol conversion and 85% methylamine plus dimethylamine selectivity could be achieved due to the combined contribution of strong acid sites, suitable acid distribution, and narrow pore dimensions of DNL-6.