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 : H. Snaith (검색결과 6 건)
- 무료
- 기관 내 무료
- 유료
-
Haloes at the ragged edge: the importance of the splashback radius
Snaith, O. N.,Bailin, J.,Knebe, A.,Stinson, G.,Wadsley, J.,Couchman, H. Oxford University Press 2017 MONTHLY NOTICES- ROYAL ASTRONOMICAL SOCIETY Vol.472 No.3
<P>We have explored the outskirts of dark matter haloes out to 2.5 times the virial radius using a large sample of haloes drawn from Illustris, along with a set of zoom simulations (MUGS). Using these, we make a systematic exploration of the shape profile beyond Rvir. In the mean sphericity profile of Illustris haloes, we identify a dip close to the virial radius, which is robust across a broad range of masses and infall rates. The inner edge of this feature may be related to the virial radius and the outer edge with the splashback radius. Due to the high halo-to-halo variation, this result is visible only on average. However, in four individual haloes in the MUGS sample, a decrease in the sphericity and a subsequent recovery is evident close to the splashback radius. We find that this feature persists for several Gyr, growing with the halo. This feature appears at the interface between the spherical halo density distribution and the filamentary structure in the environment. The shape feature is strongest when there is a high rate of infall, implying that the effect is due to the mixing of accreting and virializing material. The filamentary velocity field becomes rapidlymixed in the halo region inside the virial radius, with the area between this and the splashback radius serving as the transition region. We also identify a long-lasting and smoothly evolving splashback region in the radial density gradient in many of the MUGS haloes.</P>
-
-
Song, S.,Horantner, M.,Choi, K.,Snaith, H.,Park, T. Royal Society of Chemistry 2017 Journal of materials chemistry. A, Materials for e Vol.5 No.8
<P>We introduce 1 step pin-hole free CH(3)NH(3)PbI(3-x)C(l)x perovskite layers by using heated airflow during the nucleation stage of the perovskite. Upon employing heated air, we stimulate uniformly distributed nuclei growth, resulting in a pin-hole free planar perovskite layer. We find an optimized heated airflow of 100 degrees C as the optimized condition. The resulting planar device employing a conventional TiO2 electron transporting layer exhibits 17.6% average power conversion efficiency with 14.3% maximum powerpoint (MPP) efficiency. In addition, our method gives a very reproducible perovskite layer. Thus, our pin-hole free perovskite layer allows for 14.9% efficiency in a larger area device (0.71 cm(2)) that is generally prone to shunting paths.</P>
-
Interfacial electron accumulation for efficient homo-junction perovskite solar cells
Song, Seulki,Moon, Byung Joon,Hö,rantner, Maximilian T.,Lim, Jongchul,Kang, Gyeongho,Park, Min,Kim, Jin Young,Snaith, Henry J.,Park, Taiho Elsevier 2016 Nano energy Vol.28 No.-
<P><B>Abstract</B></P> <P>Here we study perovskite solar cells based on mesoporous alumina scaffold infiltrated and capped with a perovskite absorber layer, which are devoid of a discrete n-type electron collection layer. We employ ethoxylated polyethylenimine (PEIE) to modify the interface between the perovskite absorber layer and the metallic transparent fluorine-doped SnO<SUB>2</SUB> (FTO) electrode. Surprisingly, the PEIE interlayer obviates the requirement for the conventional dense-TiO<SUB>2</SUB> (d-TiO<SUB>2</SUB>) compact layer (or organic fullerene layer), usually required to selectively extract electrons from the perovskite film. The self-organized PEIE interlayer produced a strong induced dipole moment at the perovskite-FTO interface, with our results indicating that electrons accumulate within the perovskite film at this interface. The resultant “n-type” contact region within the perovskite absorber layer, progressing to an intrinsic (i) region within the bulk of the perovskite layer, represents an n-i homojunction and favorably enables selective electron extraction at the FTO electrode. Resulting solar cells deliver current-voltage measured power conversion efficiencies (η) of over 15.0% and a substantial stabilized efficiency (η) of 9.1%. Although our solar cell performance remains lower than the highest reported efficiencies for perovskite solar cells employing discrete charge selective extraction layers, it indicates significant potential for “homo-junction” perovskite solar cells, once the metallic-to-perovskite contact is fully controlled. Additionally, our work identifies the potential impact of modifying the interface between the perovskite absorber and the subsequent contact materials with dipolar organic compounds, which may be applicable to optimizing contact at perovskite-semiconductor heterojunctions.</P> <P><B>Highlights</B></P> <P> <UL> <LI> N-type less perovskite is proposed with stabilized power output efficiency. </LI> <LI> PEIE interlayer make an induced dipole at perovskite interface. </LI> <LI> Band bending of perovskite layer induces the charge accumulation. </LI> <LI> Perovskite solar cell have a permanent built-in potential which gives a stabilized maximum power output efficiency without n-type electron selective layer. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>
-
Efficient Single‐Layer Polymer Light‐Emitting Diodes
Kabra, Dinesh,Lu, Li Ping,Song, Myoung Hoon,Snaith, Henry J.,Friend, Richard H. WILEY‐VCH Verlag 2010 Advanced Materials Vol.22 No.29
<P><B>Single‐layer polymer light‐emitting diodes</B> are fabricated using poly (9,9′‐dioctylfluorene)‐<I>co</I>‐ benzothiadiazole (F8BT) as the emissive layer in contact with metal oxide injection layers ITO/ZnO/Cs<SUB>2</SUB>CO<SUB>3</SUB>/F8BT/MoO<SUB>3</SUB>/Au. Luminous efficiencies of up to 23 cd A<SUP>−1</SUP> are achieved for polymer layer thicknesses near 1 <I>μ</I>m. </P>
-
Hassan, Yasser,Ashton, Olivia J.,Park, Jong Hyun,Li, Guangru,Sakai, Nobuya,Wenger, Bernard,Haghighirad, Amir-Abbas,Noel, Nakita K.,Song, Myoung Hoon,Lee, Bo Ram,Friend, Richard H.,Snaith, Henry J. American Chemical Society 2019 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY - Vol.141 No.3
<P>Metal halide perovskites are promising candidates for use in light emitting diodes (LEDs), due to their potential for color tunable and high luminescence efficiency. While recent advances in perovskite-based light emitting diodes have resulted in external quantum efficiencies exceeding 12.4% for the green emitters, and infrared emitters based on 3<I>D</I>/2D mixed dimensional perovskites have exceeded 20%, the external quantum efficiencies of the red and blue emitters still lag behind. A critical issue to date is creating highly emissive and stable perovskite emitters with the desirable emission band gap to achieve full-color displays and white LEDs. Herein, we report the preparation and characterization of a highly luminescent and stable suspension of cubic-shaped methylammonium lead triiodide (CH<SUB>3</SUB>NH<SUB>3</SUB>PbI<SUB>3</SUB>) perovskite nanocrystals, where we synthesize the nanocrystals via a ligand-assisted reprecipitation technique, using an acetonitrile/methylamine compound solvent system to solvate the ions and toluene as the antisolvent to induce crystallization. Through tuning the ratio of the ligands, the ligand to toluene ratio, and the temperature of the toluene, we obtain a solution of CH<SUB>3</SUB>NH<SUB>3</SUB>PbI<SUB>3</SUB> nanocrystals with a photoluminescence quantum yield exceeding 93% and tunable emission between 660 and 705 nm. We also achieved red emission at 635 nm by blending the nanocrystals with bromide salt and obtained perovskite-based light emitting diodes with maximum electroluminescent external quantum efficiency of 2.75%.</P> [FIG OMISSION]</BR>
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
