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More than 90% of the world’s hydrogen (H₂) is produced from fossil fuel sources, which requires energy-intensive separation and purification to produce high-purity H₂fuel and to capture the carbon dioxide (CO₂) by-product. While membranes can decarbonize H₂/CO₂separation, their moderate H₂/CO₂selectivity requires secondary H₂purification by pressure swing adsorption. Here, we report hyperselective carbon molecular sieve hollow fiber membranes showing H₂/CO₂selectivity exceeding 7000 under mixture permeation at 150°C, which is almost 30 times higher than the most selective nonmetallic membrane reported in the literature. The membrane is able to maintain an ultrahigh H₂/CO₂selectivity over 1400 under mixture permeation at 400°C. Pore structure characterization suggests that highly refined ultramicropores are responsible for effectively discriminating the closely sized H₂and CO₂molecules in the hyperselective carbon molecular sieve membrane. Modeling shows that the unprecedented H₂/CO₂selectivity will potentially allow one-step enrichment of fuel-grade H₂from shifted syngas for decarbonized H₂production. 

Abstract The cost‐effective and scalable synthesis and patterning of soft nanomaterial composites with improved electrical conductivity and mechanical stretchability remains challenging in wearable devices. This work reports a scalable, low‐cost fabrication approach to directly create and pattern crumpled porous graphene/NiS₂nanocomposites with high mechanical stretchability and electrical conductivity through laser irradiation combined with electrodeposition and a pre‐strain strategy. With modulated mechanical stretchability and electrical conductivity, the crumpled graphene/NiS₂nanocomposite can be readily patterned into target geometries for application in a standalone stretchable sensing platform. By leveraging the electrical energy harvested from the kinetic motion from wearable triboelectric nanogenerator (TENG) and stored in micro‐supercapacitor arrays (MSCAs) to drive biophysical sensors, the system is demonstrated to monitor human motions, body temperature, and toxic gas in the exposed environment. The material selections, design strategies, and fabrication approaches from this study provide functional nanomaterial composites with tunable properties for future high‐performance bio‐integrated electronics. 

Enzymatic multicomponent carbon-carbon (C–C) bond–forming reactions for diversity-oriented synthesis remain rare. Using cooperative photobiocatalysis, we developed a stereoselective three-component radical-mediated C–C coupling previously unknown in both organic chemistry and biochemistry. Directed evolution of repurposed pyridoxal decarboxylases enabled full fragment variability in this three-component coupling, giving rise to six classes of valuable products, many of which were inaccessible with other methods, even in a racemic fashion. This enzymatic platform integrates a range of asymmetric catalysis principles, including remote stereocenter construction, stereodivergent catalysis, kinetic resolution, and parallel kinetic resolution, achieving excellent diastereo- and enantiocontrol over radical intermediates. The broad substrate scope and complementary specificities of evolved enzyme variants enabled combinatorial library synthesis, affording structurally and stereochemically diverse scaffolds for medicinal chemistry.