Oxygen-rich porous carbon is of great interest for energy storage applications due to its improved local electronic structures compared with unmodified porous carbon. However, a tunable method for the preparation of oxygen-rich porous carbon with a special microstructure is still worth developing. Herein, a novel modification of porous carbon with different microstructures is facilely prepared via low-temperature solvothermal and KOH activation methods that employ the coal tar and eight substances, such as cellulose as carbon source and modifier, respectively. By testing the yield, surface group structure, lattice structures, morphology, thermal weight loss, and specific capacitance of carbonaceous mesophase, cellulose–hydrochloric acid is identified as the additive for the preparation of oxygen-rich coal tar-based porous carbon. The obtained porous carbon displays a specific surface area of up to 859.49 m2 g− 1 and an average pore diameter of 2.39 nm. More importantly, the material delivers a high capacity of 275.95 F g− 1 at 0.3 A g− 1 and maintains a high capacitance of 220 F g− 1 even at 10 A g− 1. When in a neutral electrolyte, it can still retain a reversible capacity of 236.72 F g− 1 at 0.3 A g− 1 and 136.79 F g− 1 at 10 A g− 1. This work may provide insight into the design of carbon anode materials with high specific capacity.

In this study, we investigate the opportunity of using waste tire char as a cathode material for lithium-ion primary batteries (LPBs). The char obtained by carbonizing waste tires was washed with acid and thermally fluorinated to produce CFX. The structural and chemical properties of the char and CFX were analyzed to evaluate the effect of thermal fluorination. The carbon structure of the char was increasingly converted to CFX structure as the fluorination temperature increased. In addition, the manufactured CFX- based LPBs were evaluated through electrochemical analysis. The discharge capacity of the CFX reached a maximum of 800 mAh/g, which is comparable to that of CFX- based LPBs manufactured from other carbon sources. On the basis of these results, the use of waste tire char-based CFX as a cathode material for LPBs is presented as a new opportunity in the field of waste tire recycling.

The electrochemical type gas sensor has the advantage of being easy to use due its small size, and it is also relatively inexpensive. However, its output can easily vary depending on temperature and humidity conditions. Therefore, it is important to ascertain the exact output characteristics of a sensor according to the measuring environment in order to improve measurement accuracy for any set of given conditions. The purpose of this study is to obtain basic information about the output characteristics of a sensor that is used both indoor and outdoor according to the variation in temperature and humidity conditions in order to improve the accuracy of the sensor. To achieve this result, a calibration curve was made using ammonia standard gas and the calibration factor was calculated using the calibration curve and the measuring accuracy was confirmed with regard to the ammonia sensor. Based on the test results, the variation of the sensor output value was large in relation to temperature and humidity variation. It was found that the output value from the sensor at higher temperature and humidity conditions was also higher. However, the measuring accuracy of the sensor could be improved by more than 10% by applying the calibration factor and an average accuracy of more than 97% could be achieved. It is anticipated that the result of this study can be used as basic data to obtain more accurate results using electrochemical sensors for a given set of temperature and humidity conditions, and therefore, it can also be considered that the reliability and applicability of electrochemical sensors can be improved.

The electrochemical properties of poly(a-methylbenzyl dipropargylamine) was studied by cyclic voltametry. Poly(a-methylbenzyl dipropargylamine) was prepared by the cyclopolymerization of a-methylbenzyl dipropargylamine in high yield. The photoluminescence peaks of the present polymer was observed at 443nm corresponding to the photon energy of 2.80 eV. The cyclovoltamograms of the polymer exhibited the irreversible electrochemical behaviors between the doping and undoping peaks. It was found that the kinetics of the redox process of poly(MBDA) might be mainly controlled by the electron transfer process from the experiment of the oxidation current density of poly(MBDA) versus the scan rate.

In this study, several kinds of active carbons with high specific surface area and micro pore structure were prepared from the coconut shell charcoal using chemical activation method. The physical property of prepared active carbon was investigated by experimental variables such as activating chemical agents to char coal ratio, flow rate of inert gas and temperature. It was shown that chemical activation with KOH and NaOH was successfully able to make active carbons with high surface area of 1900~2500 m2/g and mean pore size of 1.85~2.32 nm. The coin cell using water-based binder in the electrolyte of LiPF6 dissolved in mixed organic solvents (EC:DMC:EMC=1:1:1 vol%) showed better capacity than that of oil-based binder. Also, it was found that the coin cell of water-based binder shows an improved cycling performance and coulombic efficiency.

본 연구에서는 내식성이 우수한 동합금에 대하여 내구성 향상을 위해 쇼트피닝 시간을 변수로 표면 개질하여 전기화학적 특성과 조직 변화를 관찰하였다. 그 결과 쇼트피닝 후 표면에 전체적으로 요철이 발생하였으며, 시간이 증가할수록 커버리지 향상에 따른 균질화 현상이 관찰되었다. 또한 쇼트피닝된 모든 시험편에서 경도가 향상되었으며, 쇼트피닝 시간이 3.5분일 때 52 %의 경도향상을 나타냈다. 그리고 이때 전기화학적 특성은 쇼트피닝을 실시하지 않은 경우와 유사하였다