http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : Dolocan, Andrei (검색결과 2 건)
- 무료
- 기관 내 무료
- 유료
-
INVERSION OF THE ELECTRICAL AND OPTICAL PROPERTIES OF PARTIALLY OXIDIZED HEXAGONAL BORON NITRIDE
AVINASH P. NAYAK,DEJI AKINWANDE,ANDREI DOLOCAN,JONGHO LEE,HSIAO-YU CHANG,TWINKLE PANDHI,MILO HOLT 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2014 NANO Vol.9 No.1
By acoustically irradiating pristine, white, electrically insulating h-BN in aqueous environmentwe were able to invert its material properties. The resulting dark, electrically conductive h-BN(referred to as partially oxidized h-BN or PO-hBN) shows a signi¯cant decrease in opticaltransmission ( > 60%) and bandgap (from 5.46 eV to 3.97 eV). Besides employing a wide variety ofanalytical techniques (optical and electrical measurements, Raman spectroscopy, SEM imaging,EDS, X-Ray di®raction, XPS and TOF-SIMS) to study the material properties of pristine andirradiated h-BN, our investigation suggests the basic mechanism leading to the dramatic changesfollowing the acoustic treatment. We ¯nd that the degree of inversion arises from the degree of h-BN surface or edge oxidation which heavily depends on the acoustic energy density provided tothe pristine h-BN platelets during the solution-based process. This provides a facile avenue for therealization of materials with tuned physical and chemical properties that depart from the intrinsicbehavior of pristine h-BN.
-
Li, Wangda,Kim, Un-Hyuck,Dolocan, Andrei,Sun, Yang-Kook,Manthiram, Arumugam American Chemical Society 2017 ACS NANO Vol.11 No.6
<P>The formation of metallic lithium microstructures in the form of dendrites or mosses at the surface of anode electrodes (e.g., lithium metal, graphite, and silicon) leads to rapid capacity fade and poses grave safety risks in rechargeable lithium batteries. We present here a direct, relative quantitative analysis of lithium deposition on graphite anodes in pouch cells under normal operating conditions, paired with a model cathode material, the layered nickel-rich oxide LiNi0.61Co0.12Mn0.27O2, over the course of 3000 charge discharge cycles. Secondary-ion mass spectrometry chemically dissects the solid electrolyte interphase (SEI) on extensively cycled graphite with virtually atomic depth resolution and reveals substantial growth of Li-metal deposits. With the absence of apparent kinetic (e.g., fast charging) or stoichiometric restraints (e.g., overcharge) during cycling, we show lithium deposition on graphite is triggered by certain transition-metal ions (manganese in particular) dissolved from the cathode in a disrupted SEI. This insidious effect is found to initiate at a very early stage of cell operation (<200 cycles) and can be effectively inhibited by substituting a small amount of aluminum (similar to 1 mol %) in the cathode, resulting in much reduced transition-metal dissolution and drastically improved cyclability. Our results may also be applicable to studying the unstable electrodeposition of lithium on other substrates, including Li metal.</P>
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
