Synthesis of metastable carbon-silicon nitride by non-equilibrium processing : ion implantation

Issued as Final report, Project no. E-18-X3

Bloody, Brutal, and Barbaric?:Wrestling with Troubling War Texts [review] / Webb, William J., and Gordon K. Oeste.

This is a book revie

Recent Progress in Carbon Electrodes for Efficient and Cost-Benign Perovskite Optoelectronics

With popularity of the perovskite optoelectronics, its material properties and device performances have been widely studied. However, the issues in cost management and continuous fabrication still hinder the commercialization of the perovskite optoelectronics. Especially, the conventional electrodes such as metal and transparent conducting oxide (TCO) have limitations due to the difficulties in fabrication which requires high temperature and vacuum processes, largely increasing the time and cost. Therefore, carbon materials with high electric conductivity and favorable work function are recently being noticed as alternatives to the conventional electrodes since the carbon materials are abundant in nature and low in the fabrication cost. Therefore, carbon electrode for the perovskite optoelectronics is widely studied to replace the conventional electrode, and utilizing carbon as an electrode can be the alternative solution for a future electrode model. In this review, the recent progress of carbon electrodes in perovskite optoelectronics and various applications will be discussed. [GRAPHICS] .N

Enhancement of the electrochemical properties of o-LiMnO2 cathodes at elevated temperature by lithium and fluorine additions

Orthorhombic LiMnO2 cathodes suffer severe capacity fading due to accelerated manganese dissolution at elevated temperatures. Fluorine-modified LiMnO2 cathodes prepared by a solid-state reaction show less cation mixing and a well-defined crystallinity with a larger grain/powder morphology. The cathodes exhibit improved capacity retention and rate capability at the elevated temperature (55 ??C) compared with undoped counterparts.close121

Synthesis of stable iodoplumbate and perovskite for efficient annealing‐free device and long‐term storage

Abstract As a next‐generation photovoltaic device, perovskite solar cells are rapidly emerging. Nevertheless, both solution and device stability pose challenges for commercialization due to chemical degradation caused by internal and external factors. Especially, the decomposition of iodoplumbate in a perovskite solution hinders the long‐term use of perovskite solutions. Moreover, the synthesis of stable perovskites at low temperature is important for stable devices and wide applications (flexible devices and high reproducibility). Herein, the critical composition of perovskite is found to obtain high stabilities of both iodoplumbate and perovskite crystals by utilizing CsPbBr3 and FAPbI3, exhibiting high device performance and long‐term solution storage. The novel composition of CsPbBr3‐alloyed FAPbI3 not only crystallizes under annealing‐free conditions but also demonstrates excellent iodoplumbate stability for 100 days (∼3000 h) without any degradation. Furthermore, high device stabilities are achieved over 2000 and 3000 h under extreme conditions of A.M. 1.5 and 85°C/85% relative humidity, respectively. Overall, the device exhibited a high power conversion efficiency of 23.4%, and furthermore, CsPbBr3‐alloyed FAPbI3 was devoted to widen the applications in both flexible and carbon‐electrode devices, thereby addressing both scientific depths and potential commercial materials

Study on the Aging Behavior of Natural Rubber/Butadiene Rubber (NR/BR) Blends Using a Parallel Spring Model

Natural rubber/butadiene rubber (NR/BR) blends are widely used in industrial areas for absorbing vibrations and shocks because of their excellent elastic stability. However, when an industrial-equipment surface is exposed to sunlight and oxygen over a long period of time, the rubber hardens. As a result, the tensile properties of the rubber material and the behavior of the strain-energy density function are changed, greatly reducing the performance of the rubber product. However, only a few experimental studies on the aging characteristics of NR/BR blends are available, and it is difficult to find a study that analyzes the organic relationship of the changes in the mechanical (stress–strain curves, strain-energy density, etc.) and chemical (cross-linked structure, crosslink density, etc.) properties. In this study, a swelling test was performed on an aged rubber compound, and the result was substituted into the Flory–Rehner equation to obtain the quantitative crosslink density. The results revealed a linear relationship between the strain-energy density (SED) and the crosslink density (CLD) when the cross-linked structure increase was represented by a parallel spring model. Finally, the relationship between the strain-energy density and the crosslink density was summarized as a formula, and a method for predicting the aging behavior of NR/BR blends using the crosslink density was proposed