SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4477-7
The rapid demand for high-energy-density lithium batteries necessitates advanced solid-state electrolytes (SSEs) to overcome the safety and performance limitations of conventional liquid counterparts. Macrocyclic compounds, with their well-defined cavities, programmable binding sites, and tunable self-assembly, have emerged as powerful molecular regulators for designing next-generation SSEs. This review examines recent advancements in macrocyclic compound-based SSEs by categorizing their functions into four fundamental supramolecular regulation paradigms: cation-centered regulation (e.g., crown ethers), anion-centered regulation (e.g., calixarenes and calixpyrroles), channel-dominated transport (e.g., cyclodextrins), and hybrid regulation (e.g., cucurbiturils). We elucidate how these macrocycles precisely control ion coordination, modulate migration dynamics, and reshape interfacial chemistry, leading to enhanced ionic conductivity, improved Li+ transference numbers, suppressed lithium dendrite growth, and superior interfacial stability. While each paradigm offers distinct advantages, the most promising SSEs often leverage synergistic combinations of these strategies. Finally, we highlight the remaining challenges, including synthetic complexity and multi-objective performance trade-offs, and propose future research directions for developing highly efficient and durable macrocycle-based solid-state lithium batteries.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3689-9
Converting body heat into electricity presents an appealing route for sustainably powering wearable electronics; however, conventional thermoelectric materials face significant drawbacks, including high ionic concentrations, toxicity, and limited thermoelectric efficiency. Here, we report an ionic thermoelectric hydrogel designed through precise supramolecular chemistry, utilizing dual molecular interactions: host-guest complexation of α-cyclodextrin (α-CD) with I3− ions and hydrogen bonding between polyvinyl alcohol (PVA) polymer chains and I3−. This molecularly tailored approach markedly amplifies thermoelectric performance, achieving a high thermopower of 2.21 mV/K and a tenfold enhancement in peak power output at an exceptionally low iodine concentration (10 mmol/L I− + 2.5 mmol/L I3−). The hydrogel maintains excellent biocompatibility and mechanical robustness, suitable for direct skin contact. Demonstrated applications include flexible thermoelectric devices generating nearly 100 mV from body heat and sensor arrays capable of motion and spatial temperature sensing. These results underscore the substantial potential of supramolecularly designed ionic thermoelectric hydrogels for wearable energy harvesting, personalized healthcare monitoring, and advanced human-computer interfaces.
SCIENCE CHINA Materials•2025•DOI: 10.1007/s40843-025-3385-4
Two-dimensional transition metal carbides/nitrides (MXenes) exhibit exceptional mechanical and electrical properties, positioning them as promising candidates for electronics, aerospace, and energy storage. However, assembling MXene nanosheets into high-performance macroscopic nanocomposites remains challenging due to low stress-transfer efficiency between nanosheets. This review systematically examines the role of voids within MXene-based nanocomposites, revealing that voids can paradoxically enhance performance under specific conditions. We discuss strategies to mitigate detrimental voids, including synergistic interfacial interactions, nanosheet filling, fabrication process optimization, and nanoconfined assembly. Empirical data from referenced studies indicate that void content critically influences mechanical reinforcement; for instance, graphene oxide monolayers exhibit a Young's modulus of approximately 200 GPa, while MXene monolayers reach 330 GPa. The review also highlights that controlled nanovoid dispersion in metals can increase strength by up to 50% without sacrificing ductility. We provide a roadmap for fabricating high-performance MXene-based nanocomposites, emphasizing the need to balance void elimination with intentional void engineering. This work consolidates current understanding and identifies pathways to overcome the stress-transfer bottleneck, enabling scalable production of MXene composites with tailored properties for demanding applications.