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Various porous materials have shown a great promise as dry sorbents for carbon dioxide (CO2) capture utilizing their large surface areas. Although there have been considerable efforts to find optimal pore size and geometry for a variety of porous materials, systematic experimental study covering various key parameters beside CO2 uptake, such as isosteric heat and selectivity against other gas, is unavailable. Here, we systemically investigate the pore size effect on the CO2 uptake and selectivity for porous activated carbon. We found that at each temperature and pressure, there exists an optimal intermediate activation condition that makes the pore size most appropriate for CO2 uptake and selectivity. Further activation increases the pore size and weakens CO2-wall interaction. This study provides an important lesson that the pore activation of porous carbon should be controlled at an optimal intermediate point to maximize CO2-wall interaction.

Hierarchically well-developed porous graphene nanofibers comprising N-doped graphitic C (NGC)-coated cobalt oxide hollow nanospheres are introduced as anodes for high-rate Li-ion batteries. For this, three strategies, comprising the Kirkendall effect, metal-organic frameworks, and compositing with highly conductive C, are applied to the 1D architecture. In particular, NGC layers are coated on cobalt oxide hollow nanospheres as a primary transport path of electrons followed by graphene-nanonetwork-constituting nanofibers as a continuous and secondary electron transport path. Superior cycling performance is achieved, as the unique nanostructure delivers a discharge capacity of 823 mAh g-1 after 500 cycles at 3.0 A g-1 with a low decay rate of 0.092% per cycle. The rate capability is also noteworthy as the structure exhibits high discharge capacities of 1035, 929, 847, 787, 747, 703, 672, 650, 625, 610, 570, 537, 475, 422, 294, and 222 mAh g-1 at current densities of 0.5, 1.5, 3, 5, 7, 10, 12, 15, 18, 20, 25, 30, 40, 50, 80, and 100 A g-1 , respectively. In view of the highly efficient Li+ ion/electron diffusion and high structural stability, the present nanostructuring strategy has a huge potential in opening new frontiers for high-rate and long-lived stable energy storage systems.

We prospectively recruited 10 patients who presented with urinary retention as a neurological deficit that was attributable to lateral medullary infarction. Of these, 9 patients underwent a urodynamic study, which demonstrated detrusor underactivity of the bladder in 7 patients. Urinary retention developed mainly when the lesions involved the lateral tegmentum of the middle or caudal medulla. We concluded that interruption of the descending pathway from the pontine micturition center to the sacral spinal cord in the lateral medulla was responsible for the development of urinary retention.

An encapsulated sulfur electrode for Li—S rechargeable batteries consisting of well aligned monoclinic sulfur nanowires completely covered by a minimal amount of carbon shows excellent electrical performance.

The study has developed a facile polydopamine (PD) surface coating method for a typical conductive additive, Super-P. This method is efficient, economical, and environmentally friendly, and it can be used for the mass production of Super-P. PD treatment converts the hydrophobic surfaces of Super-P into hydrophilic surfaces, facilitating slurry preparation, and slurry coating for the fabrication of Si-based electrodes. Furthermore, the unique adhesion properties of PD and its ability to form a cross-linking network with polymeric binders such as poly(acrylic acid) improve the cycle performance of Si anodes containing PD-treated Super-P (1395.1 mAh g–1 after 1000 cycles, and 1200 mA g–1 for charging and discharging processes). A postmortem scanning electron microscopy study reveals that PD-treated Super-P efficiently reduces the mechanical stress of Si anodes caused by large volumetric changes that occur during lithiation and delithiation.

Spray pyrolysis is a promising aerosol process to produce “designer particles” of precisely controlled morphology with decorations on surfaces or inside particles. Need of precise control of properties has sparked researches on aerosol process that may replace conventional processes such as solid state reaction process or liquid precipitation method. However, productivity is the biggest obstacle in the development of a commercial scale process because the aerosol process is essentially operated at low particle concentration compared to liquid phase processes. In this review, by reviewing publications for the last 10 years we discuss how researchers on spray pyrolysis circumvent this inherent limitation of the aerosol process. First, the process of particle design by spray pyrolysis is introduced. Some key criteria are explained for selecting each component of spray pyrolysis: precursor, additive, carrier gas, heat source, and reactor type. Second, key contributions of major groups in Korea, Japan, Europe, and America are described. Third, some of named processes to overcome productivity of spray aerosol process are introduced. Fourth, applications of spray pyrolysis to materials related to alternative energy, environmental cleaning, information processing and display, and biomaterials are considered. Finally, future prospects of spray pyrolysis are discussed along with current standing issues for further progress of spray pyrolysis.