Kyung-Wan Nam

Biopolymer-based hydrogels offer adaptable platforms for localized cancer therapy by regulating administration, tissue retention, payload protection, and therapeutic release. This review critically examines polysaccharide-, protein-, peptide-, and polynucleotide-based hydrogels, relating polymer composition, crosslinking, network architecture, swelling, degradation, and payload interactions to pharmaceutical and biological performance. Physical, chemical, enzymatic, and ionic gelation strategies are evaluated alongside diffusion-, swelling-, affinity-, and degradation-controlled release and their mathematical interpretation. Macrogels, microgels, nanogels, and hybrid systems are compared according to administration route, disposition, and oncology-relevant function. The review further distinguishes local placement, passive accumulation, ligand-mediated cellular interactions, and endogenous or externally triggered release. Applications in chemotherapy, radiotherapy, immunotherapy, hyperthermia, and phototherapy are assessed across colorectal, gastric, liver, pancreatic, and breast cancers. Marketed devices, patented technologies, clinically evaluated systems, and regulatory considerations are also examined. Despite extensive preclinical development, translation remains constrained by polymer variability, incomplete pharmaceutical characterization, sterilization and scale-up challenges, uncertain degradation and clearance, and limited clinically representative evidence. Progress will depend on clinically defined product design, reproducible manufacturing, quantitative disposition and safety assessment, and demonstration of meaningful benefit over existing therapeutic or procedural alternatives.

Deciphering the synthetic origin of oxygen‐redox stability is critical to the design of high‐capacity sodium‐ion cathodes. Although prior studies have correlated electrochemical behavior with pre‐formed structural motifs, the pathways by which these motifs emerge during synthesis remain unclear. Here, we track the structural evolution of layered sodium manganese oxide during solid‐state synthesis using time‐resolved X‐ray diffraction coupled with a real‐time micro‐furnace. We show that oxygen uptake and Mn oxidation occur predominantly during cooling, triggering oxygen‐mediated reconstruction into a framework enriched with manganese vacancies (□Mn) and stacking faults. By kinetically regulating the cooling process, we reveal that slow cooling promotes a spatially homogeneous stacking‐fault‐rich architecture that suppresses in‐plane Mn migration and mitigates irreversible O ₂ release. High‐resolution microscopy directly visualizes the development of stacking faults, while density functional theory shows that these defects substantially increase the barrier for Mn migration. Together, these findings identify cooling‐driven oxygen‐mediated reconstruction as a previously underappreciated synthetic lever for defect engineering and establish a general design principle for stabilizing oxygen redox in layered sodium cathodes.

Hydrogel-based drug delivery systems are redefining cancer therapy by enabling targeted, biocompatible, and stimuli-responsive treatment strategies. This review examines natural biopolymer hydrogels—such as chitosan, hyaluronic acid, alginate, gelatin, and collagen—and their role in precision oncology. These materials offer biodegradability, tunable properties, and low immunogenicity, supporting controlled drug release. We discuss gelation mechanisms, structural classifications from macrogels to nanogels, and the integration of stimuli-responsive features triggered by pH, temperature, light, and redox conditions within tumor microenvironments. Applications include chemotherapy, radiotherapy, immunotherapy, and phototherapy, using strategies such as passive targeting via the enhanced permeability and retention effect, active targeting via ligand functionalization, and stimuli-triggered release. Cancer-specific implementations in colorectal, gastric, liver, pancreatic, and breast tumors highlight hydrogel versatility. Key challenges include scalability, regulatory compliance, and tumor heterogeneity, while emerging innovations in smart hydrogels, nanotechnology, and personalized medicine offer promising solutions. This review underscores the potential of biopolymer-based hydrogels to advance cancer treatment toward safer, more effective, and patient-centered approaches.

The growing demand for efficient and sustainable energy storage systems has intensified research on advanced materials for lithium–ion batteries (LIBs). Gel-based synthesis routes—particularly polymeric and chelating gel techniques—have emerged as powerful methods for designing lithium–ion battery (LIB) anode materials with tailored microstructures, composition uniformity, and enhanced electrochemical performance. These methods facilitate the transformation of solution-phase precursors into homogeneous and finely structured materials, enabling precise tuning of physicochemical properties. This review provides a comprehensive overview of the fundamental principles of polymeric and chelate gel synthesis routes, highlighting their ability in controlling particle size, morphology, and phase purity. Their applicability to a wide range of anode materials, including transition metal oxides and silicon-based composites, is discussed. The manuscript highlights LIBs anode material developments via gel precursor chemistry, structure–property relationships, and future directions toward scalable and sustainable electrode manufacturing.

Conducting polymers are extensively researched due to their remarkable characteristics, including adaptable and tunable electrical conductivity, straightforward manufacturing process, enhanced mechanical strength, lightweight composition, affordability, and convenience in handling. Furthermore, they demonstrate outstanding chemical stability and elevated thermal conductivity. Conducting polymers can be easily modified with other substances to create composites with improved performance. They are easy to integrate with other materials, such as metal oxide, metal sulfide, and metal nitride. In the energy sector, especially concerning electrochemical energy storage systems such as lithium-ion batteries (LIBs), conducting polymer composites with metal oxide, phosphate, and sulfide have shown considerable promise as electrode materials. These composites leverage synergistic effects that improve electrical conductivity, increase surface area, and prevent electrode pulverization, ultimately resulting in faster charge and discharge cycles, higher energy density, and enhanced cycling performance. This review offers a comprehensive examination of different types of conducting polymers used in LIB electrodes, provides hints regarding several synthesis methods for producing conducting polymer composites with metal oxide, phosphate, and sulfide, and discusses how the morphology of these composites influences their electrochemical performance.

Fluoride solid electrolytes (SEs), despite their extremely low ionic conductivities, offer a promising pathway for enabling 5 V-class chemistries in all-solid-state batteries (ASSBs) owing to their exceptional oxidative stability. Herein, we report a new amorphous oxyfluoride SE, Li_1+xTaO_xF_6-x (x = 0.0-1.0), which exhibits over 3 orders of magnitude higher Li⁺ conductivity than crystalline LiTaF₆, reaching 1.08 × 10^-6 S cm^-1 at 30 °C (x = 1.0). Pair distribution function analysis, Raman spectroscopy, and X-ray absorption spectroscopy reveal an extended, corner-sharing chain of Ta(O/F)_6/7 polyhedra framework. Melt-quenching ab initio molecular dynamics simulations further demonstrate that this interconnected structure broadens Li⁺ diffusion pathways. Leveraging high oxidative stability (>5 V) and improved Li⁺ conductivity, Li₂TaOF₅ was implemented as a shielding layer for 5 V-class LiNi_0.5Mn_1.5O₄ cathodes, enabling exceptional cycling performance with 85.8% capacity retention after 1000 cycles at 1.0C and 30 °C. Even under high-mass-loading (49.3 mg cm^-2) or low-temperature (-20 °C) conditions, the modified LNMO electrodes with Li₂TaOF₅ exhibited promising performance, achieving >5.9 mAh cm^-2 with 94% retention. These findings underscore the efficacy of amorphization in advancing fluoride SEs and provide key design insights for advanced halide SEs in high-voltage ASSBs.

Heteroatom doping offers a unified and energy‐efficient strategy to tailor the electronic structure of carbon nanotubes (CNTs) for multifunctional energy applications. In this study, boron‐doped CNTs (B‐CNTs) synthesized via a single‐step arc discharge method are evaluated across four domains: thermal energy storage, photothermal conversion, lithium‐ion batteries, and thermoelectric generation. The present study benefits from p‐type defect formation in CNT, which includes a work function increase and a shifted Fermi level. In thermal energy storage, a paraffin/B‐CNT composite demonstrated superior thermal conductivity (0.303 W/m·K), latent heat capacity (144.7 J/g), and crystallinity (51.9%) due to enhanced dispersion and nanoconfinement. For photothermal conversion, the composite exhibited a broadened absorption spectrum and achieved a high efficiency of 91.0%, nearly three times higher than paraffin/As‐synthesized CNT (As‐CNT) composite. As an anode in lithium‐ion batteries, B‐CNTs delivered a reversible capacity of 361.02 mAh/g after 100 cycles, more than double that of pristine CNTs due to improved conductivity and Li ⁺ diffusion. Furthermore, in a paraffin/B‐CNT‐integrated thermoelectric module, enhanced interfacial heat transfer enabled stable heat‐source functionality and a conversion efficiency of 0.33%. These findings demonstrate the practical potential of B‐CNTs as a multifunctional material for improving performance in diverse energy storage and conversion systems.