共查询到20条相似文献,搜索用时 17 毫秒
1.
2.
Self‐Assembled Au/CdSe Nanocrystal Clusters for Plasmon‐Mediated Photocatalytic Hydrogen Evolution 下载免费PDF全文
Run Shi Yinhu Cao Yanjun Bao Yufei Zhao Geoffrey I. N. Waterhouse Zheyu Fang Li‐Zhu Wu Chen‐Ho Tung Yadong Yin Tierui Zhang 《Advanced materials (Deerfield Beach, Fla.)》2017,29(27)
Plasmon‐mediated photocatalytic systems generally suffer from poor efficiency due to weak absorption overlap and thus limited energy transfer between the plasmonic metal and the semiconductor. Herein, a near‐ideal plasmon‐mediated photocatalyst system is developed. Au/CdSe nanocrystal clusters (NCs) are successfully fabricated through a facile emulsion‐based self‐assembly approach, containing Au nanoparticles (NPs) of size 2.8, 4.6, 7.2, or 9.0 nm and CdSe quantum dots (QDs) of size ≈3.3 nm. Under visible‐light irradiation, the Au/CdSe NCs with 7.2 nm Au NPs afford very stable operation and a remarkable H2‐evolution rate of (10× higher than bare CdSe NCs). Plasmon resonance energy transfer from the Au NPs to the CdSe QDs, which enhances charge‐carrier generation in the semiconductor and suppresses bulk recombination, is responsible for the outstanding photocatalytic performance. The approach used here to fabricate the Au/CdSe NCs is suitable for the construction of other plasmon‐mediated photocatalysts. 相似文献
3.
4.
5.
6.
7.
8.
9.
10.
Yuanfang Yu Yue Sun Zhenliang Hu Xuhong An Dongming Zhou Hongzhi Zhou Wenhui Wang Kaiyang Liu Jie Jiang Dandan Yang Zainab Zafar Haibo Zeng Fengqiu Wang Haiming Zhu Junpeng Lu Zhenhua Ni 《Advanced materials (Deerfield Beach, Fla.)》2019,31(43)
Interfacial charge transfer is a fundamental and crucial process in photoelectric conversion. If charge transfer is not fast enough, carrier harvesting can compromise with competitive relaxation pathways, e.g., cooling, trapping, and recombination. Some of these processes can strongly affect the speed and efficiency of photoelectric conversion. In this work, it is elaborated that plasmon‐induced hot‐electron transfer (HET) from tungsten suboxide to graphene is a sufficiently fast process to prevent carrier cooling and trapping processes. A fast near‐infrared detector empowered by HET is demonstrated, and the response time is three orders of magnitude faster than that based on common band‐edge electron transfer. Moreover, HET can overcome the spectral limit of the bandgap of tungsten suboxide (≈2.8 eV) to extent the photoresponse to the communication band of 1550 nm (≈0.8 eV). These results indicate that plasmon‐induced HET is a new strategy for implementation of efficient and high‐speed photoelectric devices. 相似文献
11.
Metallic Nanogaps: Facile Preparation of Ultrasmall Void Metallic Nanogap from Self‐Assembled Gold–Silica Core–Shell Nanoparticles Monolayer via Kinetic Control (Adv. Mater. 29/2015) 下载免费PDF全文
Yuna Shin Jihwan Song Dongchoul Kim Taewook Kang 《Advanced materials (Deerfield Beach, Fla.)》2015,27(29):4388-4388
12.
13.
Facet‐Dependent Optical Properties Revealed through Investigation of Polyhedral Au–Cu2O and Bimetallic Core–Shell Nanocrystals 下载免费PDF全文
Michael H. Huang Sourav Rej Chun‐Ya Chiu 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(23):2716-2726
The ability to prepare Au–Cu2O core–shell nanocrystals with precise control over particle size and shape has led to the discovery of facet‐dependent optical properties in cuprous oxide crystals. The use of Au cores not only allows the successful formation of Au–Cu2O core–shell nanocrystals with tunable sizes, but also enables the observation of facet‐dependent optical properties in these crystals through the Au localized surface plasmon resonance (LSPR) absorption band. By tuning the Cu2O shell morphology from rhombic dodecahedral to octahedral and cubic structures, and thus the exposed facets, the Au LSPR band position can be widely tuned. Such facet‐dependent optical effects are not observed in bimetallic Au–Ag and Au–Pd core–shell nanocrystals with the same precisely tuned particle sizes and shapes. It is believed that similar facet‐dependent optical properties could be observed in other ionic solids and other metal–metal oxide systems. The unusually large degree of plasmonic band tuning covering from the visible to the near‐infrared region in this type of nanostructure should be quite useful for a range of plasmonic applications. 相似文献
14.
15.
Chao‐Yu Li Zhen‐Wei Yang Jin‐Chao Dong Tapan Ganguly Jian‐Feng Li 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(8)
Shell‐isolated nanoparticle‐enhanced Raman spectroscopy (SHINERS), due to its versatility, has been able to break the long‐term limitations of the material‐ and substrate‐specific generalities in the traditional field of surface‐enhanced Raman spectroscopy. With a shell‐isolated work principle, this method provides an opportunity to investigate successfully in surface, biological systems, energetic materials, and environmental sciences. Both the shell material and core morphology are being improved continuously to meet the requirements in diverse systems, such as the electrochemical studies at single crystal electrode surfaces, in situ monitoring of photoinduced reaction processes, practical applications in energy conversion and storage, inspections in food safety, and the surface‐enhanced fluorescence. Predictably, the concept of shell‐isolated nanoparticle‐enhancement could be expanded to the wider range for the performance of plasmon‐enhanced spectral modifications. 相似文献
16.
17.
18.
Peng Du Pengtao Jing Di Li Yinghui Cao Zhenyu Liu Zaicheng Sun 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(20):2454-2462
Localized surface plasmon resonance (LSPR), light scattering, and lowering the series resistance of noble metal nanoparticles (NPs) provide positive effect on the performance of photovoltaic device. However, the exciton recombination on the noble metal NPs accompanying above influences will deteriorate the performance of device. In this report, surface‐modified Ag@oxide (TiO2 or SiO2) nanoprisms with 1–2 nm shell thickness are developed. The thin film composed of P3HT/Ag@oxides and P3HT:PCBM/Ag@oxides is investigated by absorption, photoluminescence (PL), and transient absorption spectroscopy. The results show a significant absorption, PL enhancement, and long‐lived photogenerated polaron in the P3HT/Ag@TiO2 film, indicating the increase of photogenerated exciton population by LSPR of Ag nanoprisms. In the case of P3HT/Ag nanoprisms, partial PL quench and relatively short‐lived photogenerated polaron are observed. That indicates that the oxides layer can effectively avoid the exciton recombination. When the Ag@oxide nanoprisms are introduced into the active layer of P3HT:PCBM photovoltaic devices, about 31% of power conversion efficiency enhancement is obtained relative to the reference cell. All these results indicate that Ag@oxides can enhance the performance of the cell, at the same time the ultrathin oxide shell prevents from the exciton recombination. 相似文献
19.
Bipolar Carrier Transfer Channels in Epitaxial Graphene/SiC Core–Shell Heterojunction for Efficient Photocatalytic Hydrogen Evolution 下载免费PDF全文
Wei Lu Da Wang Liwei Guo Yuping Jia Manping Ye Jiao Huang Zhilin Li Yuan Peng Wenxia Yuan Xiaolong Chen 《Advanced materials (Deerfield Beach, Fla.)》2015,27(48):7986-7991
20.
Nanoconfined Nickel@Carbon Core–Shell Cocatalyst Promoting Highly Efficient Visible‐Light Photocatalytic H2 Production 下载免费PDF全文
Ke Zhang Jingrun Ran Bicheng Zhu Huanxin Ju Jiaguo Yu Li Song Shi‐Zhang Qiao 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(38)
The realization of large‐scale solar hydrogen (H2) production relies on the development of high‐performance and low‐cost photocatalysts driven by sunlight. Recently, cocatalysts have demonstrated immense potential in enhancing the activity and stability of photocatalysts. Hence, the rational design of highly active and inexpensive cocatalysts is of great significance. Here, a facile method is reported to synthesize Ni@C core–shell nanoparticles as a highly active cocatalyst. After merging Ni@C cocatalyst with CdS nanorod (NR), a tremendously enhanced visible‐light photocatalytic H2‐production performance of 76.1 mmol g?1 h?1 is achieved, accompanied with an outstanding quantum efficiency of 31.2% at 420 nm. The state‐of‐art characterizations (e.g., synchrotron‐based X‐ray absorption near edge structure) and theoretical calculations strongly support the presence of pronounced nanoconfinement effect in Ni@C core–shell nanoparticles, which leads to controlled Ni core size, intimate interfacial contact and rapid charge transfer, optimized electronic structure, and protection against chemical corrosion. Hence, the combination of nanoconfined Ni@C with CdS nanorod leads to significantly improved photocatalytic activity and stability. This work not only for the first time demonstrates the great potential of using highly active and inexpensive Ni@C core–shell structure to replace expensive Pt in photocatalysis but also opens new avenues for synthesizing cocatalyst/photocatalyst hybridized systems with excellent performance by introducing nanoconfinement effect. 相似文献