Laser-induced graphene (LIG) typically exhibits a mesostructure with a small specific surface area, which is detrimental to the electrochemical performance of micro-supercapacitors (MSCs). Herein, 3D nanostructured LIGs patterned on fluorinated polyimides (fPIs) via a laser photothermal method are reported. During laser-induced graphitization, a highly microporous structure in the LIG develops. Consequently, the patterned LIG (LIG-fPI) exhibits a very large specific surface area (1126.0 m 2 g −1 ), thereby enhancing its electrochemical performance. Specifically, in an H 2 SO 4 aqueous electrolyte, the micropatterned electrode exhibits an exceptional areal capacitance of 110 mF cm −2 (determined by cyclic voltammetry), which is 27 times higher than that of a LIG based on commercial polyimides and at least 7 times higher than that of current state-of-the-art MSCs. Furthermore, mechanically stable and flexible LIG-fPI-MSCs with an organic gel polymer electrolyte (working potential = ∼3 V) show very high power and energy densities of 0.58 mW cm −2 and 0.01 mW h cm −2 , respectively. Thus, these LIGs are promising for application in high-performance MSCs for flexible microelectronics.

This study was carried out to optimize cholesterol removal in whole egg using crosslinked β-cyclodextrin (β-CD) and to recycle the β-CD. Various factors for optimizing conditions were concentration of the β-CD, mixing temperature, mixing time, mixing speed and centrifugal speed. In the result of this study, the optimum conditions of cholesterol removal were 25% crosslinked β-CD, 40°C mixing temperature, 30 min mixing time, 1,200 rpm mixing speed and 2,810×g centrifugal speed. The recycling was repeated five times. The cholesterol removal was 92.76% when treated with the optimum conditions. After determining the optimum conditions, the recyclable yields of the crosslinked β-CD ranged from 86.66% to 87.60% in the recycling and the percentage of cholesterol removal was over 80% until third recycling. However, the cholesterol removal efficiency was decreased when the number of repeated recycling was increased. Based on the result of this study, it was concluded that the crosslinked β-CD was efficient for cholesterol removal in whole egg, and recycling is possible for only limited repeating times due to the interaction of the β-CD and egg protein.

Hybrid materials comprising graphene and palladium nanoparticles (PdNPs) are desirable for high-performance hydrogen detection because of the high specific surface area, electron mobility, and flexibility of graphene and the high electrochemical responsivity and reversibility of PdNPs. However, obtaining hybrid materials is energy-intensive and timeconsuming. Here, a facile and rapid laser photothermochemical single-step processing method to synchronously produce a nanoassembly of three-dimensional porous graphene and PdNPs from polymer films is reported. Polymers with intrinsic microporosity show high solubility in volatile solvents and miscibility with inorganic materials, allowing the fabrication of homogeneous polymer films containing Pd ligands. The films are photothermally processed using a laser to generate a nanohybrid via photoinduced thermal and chemical processes. The nanohybrid exhibits four-times-enhanced electrical conductivity compared to plain porous graphene, high crystallinity, and coherent covalent metal bonds with a homogeneous size and distribution of PdNPs in hierarchical micro/meso/ macroporous graphene structures, allowing high-performance hydrogen sensing (1 ppm) with outstanding mechanical reliability, flexibility, and durability upon bending and twisting. The nanoassembly is integrated with a wireless sensing platform, and hydrogen leakage (1 ppm) is detected using a smart phone. This laser-based nanomanufacturing of the nanoassembly can potentially be applied to wearable detector production platforms in the military and industry.

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