Min Kim

Self-Position of Au NPs in Perovskite Solar Cells: Optical and Electrical Contribution

Metallic nanoparticles (NPs) exhibit a localized surface plasmon resonance (LSPR) and act as scattering centers and subwavelength antennas, so metallic NPs can be incorporated into perovskite solar cells (PSCs) to effectively improve the light absorption of light harvesting devices. Here, we have embedded Au nanoparticles (NPs) into the hole transport layer (HTL) of the PSCs to investigate the photovoltaic effect of the PSCs with Au NPs. Interestingly, it was found that Au NPs dispersed spiro-OMeTAD HTL solution could naturally end up located near the perovskite layer as the result of the spin-coating step. Solar cell performance observations indicate that the LSPR and electrical effects of Au NPs enhance the photovoltaic response of PSCs, in spite of a slight decrease in the open-circuit voltage (VOC), by causing an incredible improvement in the photocurrent density as a dominant factor.

Positive Effects of E-Beam Irradiation in Inorganic Particle Based Separators for Lithium-Ion Battery

An inorganic separator was prepared by coating inorganic submicrometer sized particles on a nonwoven matrix followed by an E-beam irradiation treatment. Its characteristics were investigated by scanning electron microscopy, tensile strength analysis, thermogravimetric analysis, ionic conductivity measurements, and charge-discharge analysis. The mechanical and thermal properties of the separator were greatly enhanced by the simple curing under E-beam irradiation. However, there was no significant change in the morphology or ionic conductivity of the E-beam treated separator.

Effects of E-beam Irradiation on Physical and Electrochemical Properties of Inorganic Nanoparticle Separators with Different Particle Sizes

The effects of electron beam curing on the mechanical, thermal and electrochemical properties of inorganic nanoparticle based separators (IPSs) with various particle size distributions were investigated. We prepared IPSs consisting of 400 and 50 nm sized particles by varying the content of the 50 nm particles in the range from 0 to 100%. Al 2 O 3 nanoparticles were successfully coated on a porous nonwoven matrix and then the effects of e-beam irradiation treatment as a function of the particle size were investigated. As the size of particles used for the separator was decreased, the mechanical and ionic conductivity of the IPS were greatly enhanced by the simple curing procedure using e-beam irradiation. The c-rate performance of the non-cured IPS prepared by blending the 400 and 50 nm sized Al 2 O 3 was better than those of the IPSs based on the pure 400 and 50 nm particles. The c-rate performances were further improved by the e-beam treatment.

Solution processable silica thin film coating on microporous substrate with high tortuosity: application to a battery separator

A novel approach to incorporate a conformal inorganic thin layer inside 3D microporous polyolefin film is realized from a versatile solution process and applied to the preparation of a Li-ion battery separator with enhanced thermal and dimensional stability. Inorganic thin film thickness of around several tens of nanometers inside 3D micropores of a polyolefin could be systematically controlled by employing a mixed system of the silanization and epoxy–amine reaction of the UV-curable polymer and the plasma/UV ozone surface treatments. The surface-modified commercialized polyolefin separators with silica layers from the solution process show greatly improved thermal and dimensional stability compared to neat polyolefin separators, while maintaining charging/discharging performances of neat polyolefin separators, such as ionic conductivity, C-rate, and cycle life. Because of the conformal coating of the inorganic thin film inside the 3D polyolefin separator, the polyolefin separator maintains its initial dimension at high temperature, even above its melting point, which will result in improved safety of the Li-ion battery.

Clay nanosheets in skeletons of controlled phase inversion separators for thermally stable Li-ion batteries

L Shuangtai estuary wetland is the international key wetland which played an important role on purification of water quality of Liao River and the stability of regional climate. Based on sampling in this wetland and simulation experiments at the Shenyang Agricultural University lab pool, distribution characteristics of Pb in paper making wastewater, wetland soil and reeds tissue was analyzed respectively within a growing season. The removal rate of Pb was the highest by irrigation 20% concentration wastewater and the best removing effect emerged at jointing stage. For the same period, Pb content in water was least at 10 cm water depth and purifying effect was the most significant. The difference of Pb thermodynamics adsorption was remarkable in 10-40 cm depth soil. As the sampling depth increases the adsorption property of Pb was best in 10 cm soil depth where the purification effect was significant. Distribution characteristics Pb in Reed organization was different. The absorbing capability order of reed tissue to Pb was root>stem>leaves in the whole growth period.Effects of different concentrations of wastewater (chemical oxygen demands of 300, 175 and 50 mg·L-1) from a paper mill on seedling growth and antioxidant system in reeds were tested in experimental pools that simulated the wetland ecosystem. Root length, biomass and moisture content, but not shoot moisture content and plant height, significantly increased with increases in wastewater concentration. At 300 mg·L-1, shoot biomass increased by 52.5% and root biomass increased by 73.05% over the control. Malondialdehyde content, production rate of superoxide anions and hydrogen peroxide content all decreased with increasing concentration. At 300 mg·L-1, malondialdehyde content, production rate of superoxide anions and hydrogen peroxide content were 0.34, 0.24 and 0.16 times, respectively, those of the control in leaves and were 0.25, 0.19 and 0.17 times, respectively, those of the control in roots. Superoxide dismutase, peroxidase and catalase activities and ascorbic acid and glutathione contents in reeds significantly increased with increasing concentrations of wastewater. These results suggest that a concentration of 300 mg·L-1 could improve the activities of antioxidant enzymes, inhibit the generation of reactive oxygen species and reduce the generation of malondialdehyde, thus effectively alleviating the damage caused by salinity in wetland soil. 2015 pp. 379-384 Vol. 14 ISSN: 0972-6268 No. 2 Nature Environment and Pollution Technology An International Quarterly Scientific Journal Original Research Paper Nat. Env. & Poll. Tech. Website: www.neptjournal.com Received: 26-7-2014 Accepted: 20-8-2014C of water and soil by hydrocarbons has increased in recent years. Hydrocarbons are widely known to be extremely polluting with toxic, carcinogenic and mutagenic potential for humans while concern increases due to the difficulty to removing these compounds from the environment. This type of environmental contingencies arise direct effects on biota, since oil contains toxic chemicals that cause damage to plants, animals and humans but mainly on populations of microorganisms which represent an important part of the ecosystem and are key processes biogeochemicals. As an alternative to this problem bioremediation born; environmental technology as its main advantage is its versatility as it is a natural process of environmental self-sanitation and can adapt to the needs of each site. The denominated “hydrocarbonoclastic bacteria” are categorized according to the carbon source used when they are able to grow with alternative carbon sources. A number of these bacteria may yet be undiscovered and this bacterial can be used with the bioaugmentation technical to enhance the rate of remediation of contaminated natural systems by adding specific microorganisms to the system in this work used the “bacterial hydrocarbonoclastic”. Mexico is known for being one of world’s biggest oil producers and within its territory a number of natural oil seeps are found. In sites with these characteristics are known to exist hydrocarbonoclastic bacterial which have the distinctive ability to survive with hydrocarbons alone as carbon source (food) and facilitate mineralization by forming organic compounds more labile by breaking bonds. Due to the unique characteristics of these microorganisms, their use in soil environmental reclamation programs could be assumed.C change is a phenomenon of concern not only to countries in the Arab World but also to all countries all over the world, though the Arab region is at a disadvantage due to its predisposition to harsh climatic conditions. The energy sector is the main contributor to climate change which in turn results in changes in water quality and quantity, sea level, human health, food production, tourism and security. Arab World counties have attempted to adapt to or mitigate the effects of climate change but there are numerous challenges that they must overcome in order to keep up with these changes. Some mitigation factors in the industrial sector and building sector mainly those in search of substitute fuels to oil are far-reaching if the countries can cooperate in their efforts. Since the area has resources to implement comprehensive changes, it is recommended that stakeholders work together in order to achieve synchrony in their efforts.C changes have stimulated the increase in the use of renewable energy to replace fossil fuels because their lower impact on the climate. Biomass is one of the main renewable energy sources especially sugarcane that is used for production of ethanol and thermal energy. In northeastern Brazil, sugarcane is grown in the Atlantic Forest region (Zona da Mata) mainly between Alagoas and Paraiba states. This region presents great rainfall variability with high precipitation in coastal strip favoring sugarcane cultivation. However, some areas have high water deficit especially in the north portion of northeastern region. In these areas, sugarcane cultivation is limited and may become even drier in the future, according to the climate change projections generated by the main global circulation models. Thus, computational models like Century model simulating carbon cycle and nutrients dynamics in agricultural and forestry systems have been used to reproduce sugarcane behavior on several management and climate scenarios. These simulations aim to generate prior information of production to allow the adoption of adaptation strategies to avoid losses in the future. Climate scenarios projected by global climate models and regionalized for specific areas by the Eta/CPTEC model are used to simulate sugarcane potential productivity in future climate. Climate scenarios are based on greenhouse gas emission projections defined by the IPCC: A2 scenario (high emissions) and B2 (low emissions). The combined use of crop simulation models in agronomic systems with climate scenarios can become viable further analysis of the possible impacts of climate changes on potential sugarcane yield.L Cycle Assessment was applied to assess the water balance of selected locators in Laguna international industrial park Inc. and as a management tool to evaluate the overall impacts of each of the processes involved. The knowledge about life cycle assessment and industrial ecology is one of the building blocks of sustainability of water reuse in LIIP. Most of the locators do not consider yet ecological sustainability due to their limited knowledge of industrial ecology. Although most of the Pollution Control Officers are not that informed about industrial ecology and life cycle assessment, they are willing to disclose their data on volume of ground freshwater consumption and wastewater discharge. There are locators who have pre-treatment process due to their high quality requirements of water and they just discharge this pre-treated water directly to the Centralized Sewage Treatment Plant. In consonance to this, there are locators who are using water for their auxiliary operations which do not require high quality of water. Evaluation results showed that industrial ecology can be applied to selected locators so they can reduce their groundwater consumption and volume of discharged wastewater. It was identified that barriers in closing the water loop in LIIP are due to abundance of freshwater supply and its cheaper cost.