SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4473-9
Selective ion separation is critical for resource recovery, water treatment, lithium extraction from salt lakes, and nuclear waste management, yet the differences in size, solvation structure, and coordination behavior among ions are often minimal, and separation is further complicated by valence, interfacial charge, and competing ions. Nanoporous materials with tunable sub-nanometer channels and chemically active interfaces can regulate ion entry, solvation reorganization, interfacial partitioning, intrapore migration, and release. This review examines three mechanistic categories—size and solvation sieving, chemical recognition, and dynamic gating—from the perspective of confined transport and ion–pore interactions, and compares their roles and coupling in systems of monovalent–monovalent, divalent–divalent, heterovalent, and chemically similar multivalent ions. We further distinguish selective adsorption, membrane enrichment, and transmembrane transport, and discuss how selectivity definitions, ion flux, feed composition, driving force, and operating time affect performance evaluation. Current research faces three major challenges: lack of comparability of performance data across different test conditions, insufficient direct evidence of ion solvation, site occupancy, and migration under operating conditions, and the complexity of feed streams. By adopting a sequential ion transport process as a unified conceptual framework, this review systematically compares separation mechanisms across diverse nanoporous materials, including MOFs, COFs, zeolites, 2D materials, microporous polymer membranes, ion-exchange membranes, biomimetic nanochannels, organic–inorganic composites, functionalized porous carbons, and biochars. This transport-process-oriented framework provides a general and mechanistic perspective for understanding and comparing selective ion separation across diverse nanoporous platforms.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4234-3
The pursuit of high-energy-density sodium-ion batteries (SIBs) necessitates the development of stable high-capacity anodes. While amorphous carbon is a promising anode candidate for SIBs, its practical application is hindered by limited capacity. Herein, we design a composite anode by chemically confining a high-content (~25 wt%) short-chain sulfur into hierarchical porous hard carbon microspheres (SHHC) derived from microbe yeast. The SHHC anode exhibits a high reversible capacity of ~807 mAh g−1 at 0.03 A g−1 (~3 times that of conventional amorphous carbon) along with superior rate capability, and extraordinary long-term cyclability (almost 100% capacity retention after 2000 cycles at 1.0 A g−1). The high-content sulfur species contribute to superb redox reactivity for high-capacity sodium storage via a surface-dominated storage mechanism. The carbon matrix features an enlarged interlayer distance, which facilitates Na-ion intercalation and deintercalation for high-rate capability. Furthermore, the hierarchical porous structure with built-in cavities facilitates the Na-ion transfer and effectively accommodates the electrode’s volume expansion, achieving fast electrode kinetics and outstanding cyclability. Such a combination of favored properties leads to state-of-the-art comprehensive battery performance for Na-ion storage. Our finding envisions a new perspective on building stable high-capacity anode materials for SIBs.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3788-9
Fabrication of large-area perovskite solar modules under ambient air conditions remains a critical challenge due to air sensitivity of perovskite intermediate phases during crystallization. Here, we introduce 2-iodoimidazole (IIZ) into the perovskite precursor, enabling the formation of an air-stable pure δ-phase intermediate, which, upon annealing, fully transforms into a highly oriented α-phase perovskite film with reduced defects and variability. Leveraging this approach, we achieve a stabilized power conversion efficiency of 20.9% for 927.5 cm2 perovskite solar modules with high reproducibility. The encapsulated modules meet stringent international photovoltaic testing standards (IEC61215:2021), demonstrating excellent stability under continuous operation, thermal cycling (−40 to 85 °C) and damp heat (85 °C and 85% relative humidity).
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3855-8
The escalating environmental burden of plastic waste necessitates innovative chemical recycling strategies that circumvent the energy-intensive and catalytic limitations of conventional depolymerization. This study highlights a seminal advance by Qi Zhang, Da-Hui Qu, Ben L. Feringa, and co-workers, published in Nature Nanotechnology, which integrates supramolecular self-assembly with dynamic covalent chemistry to achieve catalyst-free, solvent-free polymer-to-monomer transformation. The system employs thioctic amide (TAA), a derivative of α-lipoic acid featuring reversible disulfide bonds and hydrogen-bonding amide groups. Notably, TAA monomers resist ring-opening polymerization upon melting due to cross-stacked packing driven by amide hydrogen bonds, which kinetically separates the 1,2-dithiolane rings. Introduction of formic acid (FA) as a supramolecular modulator disrupts the hydrogen-bond network, enabling dynamic disulfide ROP. Subsequent solvent removal yields nanocrystalline poly(disulfide) (Nc-poly(TAA)), which upon annealing at 120 °C reorganizes into a semicrystalline polymer (Sc-poly(TAA)) with a Young's modulus of 3.9 GPa, comparable to Nylon 6. The semicrystalline polymer exhibits hierarchical order with densely packed spherulites and periodic lamellae stabilized by reticular hydrogen bonds, conferring exceptional mechanical robustness and resistance to humidity (80% RH for six days). Rheological analyses reveal a relaxation time exceeding 90 years at room temperature, indicating a kinetically trapped, metastable state. Remarkably, the polymer reverts quantitatively to monomeric crystals under mild heating (120 °C, 24 h) without catalyst or solvent, achieving >90% purity and quantitative yield. The recovered monomer can be repolymerized to virgin-quality polymer, establishing a closed-loop cycle. Life-cycle assessment shows a carbon footprint of only 0.36 kg CO2 per kg product, underscoring the environmental benefits. This work demonstrates a fundamentally new route to circular polymers, merging supramolecular chemistry with dynamic covalent bonds for sustainable materials.