Yun Chan Kang

A novel anode material for sodium‐ion batteries consisting of 3D graphene microspheres divided into several tens of uniform nanospheres coated with few‐layered MoS 2 by a one‐pot spray pyrolysis process is prepared. The first discharge/charge capacities of the composite microspheres are 797 and 573 mA h g −1 at a current density of 0.2 A g −1 . The 600th discharge capacity of the composite microspheres at a current density of 1.5 A g −1 is 322 mA h g −1 . The Coulombic efficiency during the 600

A structure denoted as a "bubble-nanorod composite" is synthesized by introducing the Kirkendall effect into the electrospinning method. Bubble-nanorod-structured Fe2O3-C composite nanofibers, which are composed of nanosized hollow Fe2O3 spheres uniformly dispersed in an amorphous carbon matrix, are synthesized as the target material. Post-treatment of the electrospun precursor nanofibers at 500 °C under 10% H2/Ar mixture gas atmosphere produces amorphous FeOx-carbon composite nanofibers. Post-t

Double-shelled SnO2 yolk-shell-structured powders are prepared by applying a new facile one-pot process. Carbon-SnO2 composite powder particles are first formed as an intermediate product inside a tubular reactor. Step-by-step combustion of carbon from outside the composite powder particles forms the double-shelled SnO2 yolk-shell-structured powder particles. The SnO2 yolk-shell-structured powders show excellent electrochemical properties. As a service to our authors and readers, this journal pr

Multishell structured metal selenide nanocubes, namely, Co/(NiCo)Se₂ box-in-box structures with different shell compositions, were successfully synthesized by applying zeolitic imidazolate framework-67 (ZIF-67) as a template.

Yolk-shell-structured MoSe₂ microspheres were prepared via a simple selenization process of MoO₃ microspheres. The yolk-shell-structured MoSe₂ and MoO₃ microspheres delivered initial discharge capacities of 527 and 465 mA h g(-1) in the voltage range of 0.001-3 V vs. Na/Na(+) at a current density of 0.2 A g(-1), respectively, and their discharge capacities after 50 cycles were 433 and 141 mA h g(-1), respectively. The yolk-shell-structured MoSe₂ microspheres also exhibited outstanding high rate

A novel type of spherical and porous composites were synthesized to dually benefit from reduced graphene oxide (rGO) and magnetic materials as supports for enzyme immobilization. Three magnetic composite particles of Fe 3 O 4 and rGO containing 71% (rGO-Fe 3 O 4 -M1), 36% (rGO-Fe 3 O 4 -M2), and 18% (rGO-Fe 3 O 4 -M3) Fe were prepared using a one-pot spray pyrolysis method and were used for the immobilization of the model enzymes, laccase and horseradish peroxidase (HRP). The rGO-Fe 3 O 4 compos

Three-dimensional (3D) porous microspheres composed of CoSe₂@N-doped carbon nanorod-deposited carbon nanotube (CNT) building blocks (CoSe₂@NC-NR/CNT) can be successfully synthesized using CNT/Co-based metal-organic framework (ZIF-67) porous microspheres as a precursor. This strategy involves the homogeneous coating of ZIF-67 polyhedrons onto porous CNT microspheres prepared by spray pyrolysis and further selenization of the composites under an Ar/H₂ atmosphere. D

Highly porous MoSe 2 -reduced graphene oxide-carbon nanotube (MoSe 2 -rGO-CNT) powders were prepared by a spray pyrolysis process. The synergistic effect of CNTs and rGO resulted in powders containing ultrafine MoSe 2 nanocrystals with a minimal degree of stacking. The initial discharge capacities of MoSe 2 -rGO-CNT, MoSe 2 -CNT, MoSe 2 -rGO, and bare MoSe 2 powders for sodium ion storage were 501.6, 459.7, 460.2, and 364.0 mA h g –1, respectively, at 1.0 A g –1 . The MoSe 2 -rGO-CNT composite p

The first-ever study of nickel selenide materials as efficient anode materials for Na-ion rechargeable batteries is conducted using the electrospinning process. NiSe2-reduced graphene oxide (rGO)-C composite nanofibers are successfully prepared via electrospinning and a subsequent selenization process. The electrospun nanofibers giving rise to these porous-structured composite nanofibers with optimum amount of amorphous C are obtained from the polystyrene to polyacrylonitrile ratio of 1/4. These

Spray-drying and the nanoscale Kirkendall diffusion process are used to prepare nickel sulfide hollow nanospheres/reduced graphene oxide (rGO) composite powders with excellent Na-ion storage properties. Metallic Ni nanopowder-decorated rGO powders, formed as intermediate products, are transformed into composite powders of nickel sulfide hollow nanospheres/rGO with mixed crystal structures of Ni3S2 and Ni9S8 phases by the sulfidation process under H2S gas. Nickel sulfide/rGO composite powders wit

This paper introduces a facile one-pot method for synthesizing a new structured material, named "ant-cave microball", by continuous ultrasonic spray pyrolysis. The ant-cave-structured microballs are prepared from a colloidal spray solution with polystyrene nanobeads and sucrose. Networking between the nanovoids formed by decomposition of the polystyrene nanobeads results in the formation of nanochannels. The electrochemical properties of these ant-cave-structured MoO3-C microballs, prepared as t