Yun Jung Lee

Development of materials that deliver more energy at high rates is important for high-power applications, including portable electronic devices and hybrid electric vehicles. For lithium-ion (Li+) batteries, reducing material dimensions can boost Li+ ion and electron transfer in nanostructured electrodes. By manipulating two genes, we equipped viruses with peptide groups having affinity for single-walled carbon nanotubes (SWNTs) on one end and peptides capable of nucleating amorphous iron phospha

We report the synthesis and electrochemical activity of gold and silver noble metals and their alloy nanowires using multiple virus clones as anode materials for lithium ion batteries. Using two clones, one for specificity (p8#9 virus) and one versatility (E4 virus), noble metal nanowires of high-aspect ratio with diameters below 50 nm were successfully synthesized with control over particle sizes, morphologies, and compositions. The biologically derived noble metal alloy nanowires showed electr

Amorphous iron phosphate nanowires with diameters of 10 to 20 nm were synthesized using genetically engineered M13 virus for lithium ion battery cathodes. Hydrolysis of Fe3+ ions has been effectively suppressed by forming conjugates with the virus and synthesizing at low temperature, 4 °C. The M13 virus biological template facilitated elaborate nanostructure design and environmentally benign, low temperature synthesis. By implementing heterostructures with silver, we demonstrated experimentally

NdBa_0.75Ca_0.25Co₂O_5+δ-based double perovskite catalysts provide new ways for significantly enhanced oxygen-related electrochemical reactions with durable characteristics in alkaline atmospheres.

Increasing demand for flexible devices in various applications, such as smart watches, healthcare, and military applications, requires the development of flexible energy-storage devices, such as lithium-ion batteries (LIBs) with high flexibility and capacity. However, it is difficult to ensure high capacity and high flexibility simultaneously through conventional electrode preparation processes. Herein, smart conductive textiles are employed as current collectors for flexible LIBs owing to their

This review covers various strategies aimed at controlling Li deposition on a heterogeneous current collector for an anodeless cell configuration in batteries with liquid and solid-state electrolytes.

Abstract Water purification by membranes is widely investigated to address concerns related to the scarcity of clean water. Achieving high flux and rejection simultaneously is a difficult challenge using such membranes because these properties are mutually exclusive in common artificial membranes. Nature has developed a method for this task involving water‐channel membrane proteins known as aquaporins. Here, the design and fabrication of graphene oxide (GO)‐based membranes with a surface‐tethere

Core-shell carbon-coated LiFePO4 nanoparticles were hybridized with reduced graphene (rGO) for high-power lithium-ion battery cathodes. Spontaneous aggregation of hydrophobic graphene in aqueous solutions during the formation of composite materials was precluded by employing hydrophilic graphene oxide (GO) as starting templates. The fabrication of true nanoscale carbon-coated LiFePO4 -rGO (LFP/C-rGO) hybrids were ascribed to three factors: 1) In-situ polymerization of polypyrrole for constrained

We report a facile and template-free soft chemical approach that employs a low-temperature calcination treatment to synthesize a new class of materials comprising self-arranged hollow mesoporous Co3O4 and Co3O4–carbon nanotube composites. Each hollow particle is formed by a double-layered nanowall with a thickness of around 50–100 nm. The inner wall consists of a uniform amorphous layer, while the outer layer consists of self-assembled aggregates of ultrafine nanoflakes and particles. Our synthe

Li-free all-solid-state batteries can achieve high energy density and safety. However, separation of the current collector/solid electrolyte interface during Li deposition increases interfacial resistance, which deteriorates safety and reversibility. In this study, a reversible 3D porous anode is designed based on Li deposition behavior that depends on the pore size of the anode. More Li deposits are accommodated within the smaller pores of the Li hosting anode composed of Ni particles with a gr

Herein, a freestanding cellulose acetate-carbon nanotube (CA-CNT) film electrode is presented to achieve highly flexible, high-energy lithium-ion batteries (LIBs). CA serves as a dispersing agent of CNTs and a binder-free network former. A straightforward washing can remove CA in the electrode almost completely, while the fibrous CNT network within the electrode is sustained. Furthermore, the facile fabrication enables the large-scale production of the film electrode because the CA-CNT film is p

Abstract The alloying behavior of Li‐alloy‐forming metals in the anode of all‐solid‐state batteries (ASSBs) critically affects the viscoplastic flow and deposition of Li, determining cell performance. Herein, an ultra‐stable breathing Mg anode for Li‐free ASSBs is reported with changes in the inter‐particle distance of the Mg particles during operation. It is proposed that this unique Li deposition between Mg particles is derived from the Li concentration gradient (LCG) from the surface to the c