Article
Chemistry, Physical
Yutao Zhang, Yahui Li, Haijian Wen, Leitao Cao, Wenxin Xiao, Jintao Zhao, Zeyuan Nan, Suxia Zhang, Song Qiu, Qingwen Li
Summary: This study presents a novel method based on electrochemical shortening and selective adsorption to precisely control the length and distribution of single-walled carbon nanotubes (SWCNTs). Experimental results reveal that SWCNTs with smaller diameters are more prone to truncation, resulting in shorter lengths. Remarkably, a length-dependent fluorescence enhancement was observed when the length of semiconducting-SWCNTs (s-SWCNTs) was reduced to below 120 nm. This research lays the foundation for further exploration of length-dependent properties and applications of s-SWCNTs.
Article
Chemistry, Multidisciplinary
Qirui Liu, Ke Wei, Yuxiang Tang, Zhongjie Xu, Xiang'ai Cheng, Tian Jiang
Summary: The excited-state dynamics in layered tungsten disulfide (WS2) were studied using transient absorption microscopy, which revealed the ultrafast hot carrier expansion and its potential in improving carrier harvesting. A cascaded transport model was proposed to explain the carrier diffusion mechanism in this system.
Review
Energy & Fuels
Jin-Myung Choi, Jiye Han, Tushar Rane, Soyeon Kim, Ick Soo Kim, Il Jeon
Summary: This review discusses the fundamentals of utilizing SWCNTs in PSCs, including their characteristics as electron-transporting layer, hole-transporting layer, photoactive layer, and interfacial materials. It also presents strategies to improve PSCs performance through defect control and enhancement of electrical and morphological properties.
JOURNAL OF PHYSICS-ENERGY
(2022)
Article
Chemistry, Multidisciplinary
Dewu Lin, Yue Yu, Lanying Li, Mingzhi Zou, Jin Zhang
Summary: The article describes a method for synthesizing high-purity semiconducting single-walled carbon nanotube arrays using a bicomponent catalyst of Au and ZrO2, which creates a localized etching zone to improve the purity and performance of carbon nanotubes.
Article
Chemistry, Physical
Xue Zhao, Ningfei Gao, Zeyao Zhang, Qidong Liu, Jian Sheng, Yijie Hu, Ruoming Li, Haitao Xu, Lianmao Peng, Yan Li
Summary: The selective growth of semiconducting single-walled carbon nanotubes (s-SWCNTs) is achieved using CO as both catalyst reductant and carbon feedstock, along with bimetallic catalysts and quartz substrates. The CO-based process demonstrates feasibility and universality, resulting in horizontally aligned s-SWCNT arrays with high content (>97%) and potential for scalable fabrication of CNT-based devices.
Article
Chemistry, Multidisciplinary
Mengting Jiang, Stefano Pecorario, Nicolas F. F. Zorn, Jana Zaumseil, Mario Caironi
Summary: Solution-processed networks of semiconducting single-walled carbon nanotubes (SWCNTs) have potential applications in digital circuits, thermoelectric devices, and healthcare. Charge modulation microscopy (CMM) is used to study charge transport in field-effect transistors (FETs) based on different types of SWCNT networks, providing insights into the spatial distribution and evolution of free carriers during FET switching. The results show that preferential percolation paths are responsible for the transportation of holes and electrons, and the SWCNT density and band gap influence the charge density and transport paths.
ADVANCED MATERIALS INTERFACES
(2023)
Article
Nanoscience & Nanotechnology
Yongping Liao, Zhao Zhang, Qiang Zhang, Nan Wei, Saeed Ahmad, Ying Tian, Esko Kauppinen
Summary: Aerosol etching strategy has been developed to prepare high-purity semiconducting SWCNTs with increased s-SWCNT ratio. The technique offers a promising option for the high-yield synthesis of s-SWCNTs and implies potential applications in TFTs.
ACS APPLIED NANO MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Piao Xie, Yun Sun, Chao Chen, Shu-Yu Guo, Yiming Zhao, Xinyu Jiao, Peng-Xiang Hou, Chang Liu, Hui-Ming Cheng
Summary: This study selectively separated semiconducting single-walled carbon nanotubes (s-SWCNTs) with large diameters using SWCNTs with large diameters as raw materials and a conjugated polymer with long side chains as wrapping agent. The study successfully enriched s-SWCNTs with a diameter of approximately 1.9 nm, which exhibited a clean surface. Thin-film transistors constructed with the sorted s-SWCNTs as channel material showed charge-carrier mobilities higher than 10 cm(2) V-1 s(-1) and on/off ratios higher than 10(3).
Article
Chemistry, Physical
Andrea Simion, Adrian Pirnau, Flaviu R. Turcu, Adriana Vulpoi, Milica Todea, Monica Potara, Mihai Vasilescu
Summary: Functionalized multi-walled carbon nanotubes have been shown to have a direct impact on the diffusion coefficient of water, providing potential control in drug delivery applications. This study utilized NMR spectroscopy to demonstrate this effect and highlighted the importance of molecule choice in functionalization for specific diffusion control.
JOURNAL OF MOLECULAR STRUCTURE
(2022)
Article
Chemistry, Multidisciplinary
Liu Qian, Qian Shao, Yue Yu, Weiming Liu, Shanshan Wang, Enlai Gao, Jin Zhang
Summary: By utilizing a floating solid catalyst chemical vapor deposition system, the challenge of achieving high-density and high-purity semiconducting single-walled carbon nanotube arrays has been overcome. This approach allows for the growth of carbon nanotubes with high density and high purity, showing great potential for future applications in carbon nanotube electronics.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Ziyi Hu, Ben Breeze, Reza J. Kashtiban, Jeremy Sloan, James Lloyd-Hughes
Summary: This study investigated the impact of HgTe NWs synthesized inside SWCNTs on their optical and electronic properties. The results showed that the influence varied with the chirality of the SWCNTs. For semiconducting SWCNTs, HgTe NWs suppressed Auger relaxation processes and enhanced photoluminescence. On the other hand, HgTe NWs increased the Auger relaxation rate and phonon relaxation of metallic SWCNTs, boosting electronic transport.
Article
Chemistry, Physical
Er-Xiong Ding, Peng Liu, Abu Taher Khan, Qiang Zhang, Nan Wei, Hua Jiang, Esko Kauppinen
Summary: In this study, high-purity, long, and isolated s-SWCNTs were continuously produced by gas-phase synthesis, maintaining their pristine morphologies. The as-produced s-SWCNTs had a purity of 98% and a mean length of 15.2 mm. The enrichment of s-SWCNTs was found to be mainly caused by overpressure in the reactor and methanol, and the s-SWCNTs exhibited a higher negative charge and a critical role of oxygen-contained species in their synthesis. The field-effect transistors based on s-SWCNTs showed a high mean charge carrier mobility, which was 2.27 times higher than that of transistors fabricated with dispersion-processed SWCNTs. The challenges of synthesis repeatability were discussed, and recommendations for improving reproducibility were provided. This study is an important step towards the scalable production of clean, long, and isolated s-SWCNTs with high purity and narrow bandgap distribution.
Article
Chemistry, Physical
Tomitsugu Taguchi, Shunya Yamamoto, Hironori Ohba
Summary: The study successfully synthesized double-thick-walled (DTW) silicon carbide (SiC) nanotubes with unique structures and properties. Experimental results showed that DTW SiC nanotubes with perfect structures can only be synthesized with an MWCNT wall thickness of at least 50 nm.
APPLIED SURFACE SCIENCE
(2021)
Article
Chemistry, Physical
Alena A. Alekseeva, Dmitry Krasnikov, Grigoriy B. Livshits, Stepan A. Romanov, Zakhar I. Popov, Liubov A. Varlamova, Ekaterina Sukhanova, Andrei S. Klimovich, Pavel B. Sorokin, Serguei Savilov, Albert G. Nasibulin
Summary: We report a simple one-step method to selectively etch metallic single-walled carbon nanotubes (SWCNTs) in the aerosol phase. Our approach involves a tandem of two flow reactors, with the first one producing SWCNTs and the second one eliminating metallic SWCNTs. By modeling the adsorption of the oxidant (N2O) on the SWCNT surface, we found that metallic SWCNTs have lower adsorption energy than semiconducting ones. Using this method, we obtained SWCNT films enriched with semiconducting nanotubes.
Article
Polymer Science
Vijay Patel, Unnati Joshi, Anand Joshi, Blessing Kudzai Matanda, Kamlesh Chauhan, Ankit D. Oza, Diana-Petronela Burduhos-Nergis, Dumitru-Doru Burduhos-Nergis
Summary: This manuscript presents an experimental investigation of the friction and wear properties of PMMA nanocomposites reinforced with functionalized MWCNTs. The results indicate that the MWCNTs can effectively enhance the tribological performance of PMMA. The optimal MWCNT loading was found to be 0.5 wt.%, resulting in the lowest friction coefficient and wear rate.
Article
Nanoscience & Nanotechnology
Shaohua Fu, Rui Wang, Dongsheng Tang, Xiaoxian Zhang, Dawei He
Summary: A noninvasive method was developed to evaluate the coupling strength of MoSe2/CuPc HS by combining EFM and spectroscopic measurements, revealing a new Raman mode due to strong interfacial coupling. The modulation of coupling strength was successfully achieved by changing post-treatment conditions.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Nanoscience & Nanotechnology
Xiuxiu Han, Xingyao Liang, Dawei He, Liying Jiao, Yongsheng Wang, Hui Zhao
Summary: This study investigates the differences in photocarrier dynamics between different phases of MoTe2, providing important insights for future 2D optoelectronic and phase-change electronic devices based on MoTe2.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Physics, Applied
Shudi Pan, Pavel Valencia-Acuna, Weijin Kong, Jianhua Liu, Xiaohui Ge, Wanfeng Xie, Hui Zhao
Summary: The electron transfer and carrier dynamics in MoTe2/WS2/MoS2 trilayer heterostructures were investigated using transient absorption and photoluminescence measurements. It was found that the recombination of intralayer excitons in MoS2 and WS2 is significantly suppressed in the heterostructure, indicating efficient interlayer charge transfer processes. Time-resolved differential reflectance measurements showed that electrons excited in MoTe2 can transfer to MoS2 within 0.3 ps and have a long lifetime of several hundred picoseconds due to slow recombination with holes in MoTe2. The charge transfer and recombination processes were weakly dependent on the injected carrier density.
APPLIED PHYSICS LETTERS
(2021)
Article
Nanoscience & Nanotechnology
Pengzhi Wang, Dawei He, Yongsheng Wang, Xiaoxian Zhang, Xiaoyue He, Jiaqi He, Hui Zhao
Summary: Experimental study reveals ultrafast interlayer charge transfer between PtSe2 and WS2, facilitating the formation of interlayer excitons with long lifetime and diffusion length in the heterostructure.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Chemistry, Multidisciplinary
Shuangyan Liu, Dawei He, Congwei Tan, Shaohua Fu, Xiuxiu Han, Mohan Huang, Qing Miao, Xiaoxian Zhang, Yongsheng Wang, Hailin Peng, Hui Zhao
Summary: Research on the interlayer charge transfer properties of heterostructures formed by Bi2O2Se and WS2/MoS2 showed photoluminescence quenching and ultrafast charge transfer processes. These results demonstrate the feasibility of integrating 2D Bi2O2Se with other 2D semiconductors to fabricate heterostructures with novel charge transfer properties.
Article
Chemistry, Multidisciplinary
Ting Zheng, Yu-Chuan Lin, Neema Rafizadeh, David B. Geohegan, Zhenhua Ni, Kai Xiao, Hui Zhao
Summary: The charge transfer properties of van der Waals heterostructures formed by Janus and regular transition metal dichalcogenide monolayers have been studied. It is found that the charge transfer from regular to Janus monolayers is ultrafast, regardless of the direction of the Janus field. However, the charge transfer from Janus to regular layers is directional and controlled by the Janus field. The transferred carriers form interlayer excitons with extended lifetimes compared to intralayer excitons. These findings indicate that Janus structures can be utilized to create 2D heterostructures with efficient and directional charge transfer properties.
Article
Optics
Pengzhi Wang, Dawei He, Yongsheng Wang, Xiaoxian Zhang, Jiaqi He, Hui Zhao
Summary: Recently, there has been increasing interest in 2D noble metal dichalcogenides for their tunable electronic and optical properties. However, the dynamics of photocarriers in these materials have been less studied. In this study, the photocarrier dynamics in monolayer and bilayer PtSe2 samples prepared by chemical vapor deposition were investigated using transient absorption microscopy. The results showed that monolayer PtSe2 exhibited superior exciton transport properties, with a higher diffusion coefficient and deduced mobility compared to bilayer PtSe2. These findings suggest that monolayer PtSe2 is a promising material for ultrathin excitonic devices.
LASER & PHOTONICS REVIEWS
(2022)
Article
Materials Science, Multidisciplinary
Pengzhi Wang, Yongsheng Wang, Ang Bian, Shengcai Hao, Qing Miao, Xiaoxian Zhang, Jiaqi He, Dawei He, Hui Zhao
Summary: In this study, energy transfer in a van der Waals heterostructure formed by WSe2 and PtSe2 monolayers was investigated using steady-state photoluminescence and time-resolved transient absorption spectroscopy. The results showed that excitation can be transferred from WSe2 to PtSe2, but not vice versa. These findings reveal the band alignment of WSe2 and PtSe2 monolayers.
Article
Chemistry, Multidisciplinary
Jianwei Ding, Shaohua Fu, Kui Hu, Guangjie Zhang, Mengxi Liu, Xiaoxian Zhang, Rui Wang, Xiaohui Qiu
Summary: Experimental evidence of hot electron extraction at a CuPc/MoSe2 interface demonstrates the feasibility of this approach, with a proposed mechanism explaining the phenomenon. These results suggest that intersystem crossing at organic-inorganic interfaces may enable efficient hot electron extraction in photovoltaic devices.
Article
Chemistry, Multidisciplinary
Kushal Rijal, Stephanie Amos, Pavel Valencia-Acuna, Fatimah Rudayni, Neno Fuller, Hui Zhao, Hartwin Peelaers, Wai-Lun Chan
Summary: Periodic nanoscale potentials can trap interlayer excitons by utilizing the structure deformability of a 2D molecular crystal as a degree of freedom. The PTCDI lattice on MoS2 creates a spatial variation of molecular orbital energy, providing effective trapping sites for IXs.
Article
Chemistry, Multidisciplinary
Pavel Valencia-Acuna, Fatimah Rudayni, Kushal Rijal, Wai-Lun Chan, Hui Zhao
Summary: We report the generation of long-lived and highly mobile photocarriers in hybrid van der Waals heterostructures that consist of monolayer graphene, few-layer transition metal dichalcogenides, and the organic semiconductor F8ZnPc. Photocarriers in the heterostructures can achieve long recombination lifetimes and high mobility by transferring electrons from F8ZnPc to graphene and separating them from the holes in F8ZnPc. The use of these artificial heterostructures can enhance the performance of graphene-based optoelectronic devices.
Article
Physics, Applied
Ang Bian, Shuangyan Liu, Xiaoxian Zhang, Zeng Liu, Dawei He, Hui Zhao, Jun Dai
Summary: In this study, the heterostructure of WSe2/WS2 with different layer thicknesses was investigated using steady-state and transient absorption spectroscopy. Different ultrafast charge transfer behaviors were observed in 1L-WSe2/2L-WS2 and 2L-WSe2/2L-WS2 few-layer heterostructures. It was demonstrated that the layer thickness determines the sequence of intralayer exciton relaxation and interlayer charge transfer. The energy transfer induced by the layer thickness can effectively mediate the hot carrier transfer time and interlayer exciton lifetime in 2D indirect bandgap semiconductor heterostructures.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Guili Li, Xiaoxian Zhang, Yongsheng Wang, Zhiying Bai, Hui Zhao, Jiaqi He, Dawei He
Summary: This study investigates the photocarrier dynamics in PdSe2 and reveals a photocarrier lifetime of around 210 ps, a diffusion coefficient of about 7.3 cm(2) s(-1), a diffusion length of approximately 400 nm, and a photocarrier mobility of around 300 cm(2) V-1 s(-1). These findings are crucial for understanding the ultrafast optoelectronic properties of PdSe2 and for designing high-performance optoelectronic devices based on this material.
Article
Materials Science, Multidisciplinary
Ang Bian, Shaohua Fu, Pengzhi Wang, Kun Zhao, Jiaqi He, Xiaoxian Zhang, Dawei He, Yongsheng Wang, Hui Zhao
Summary: In this study, the photocarrier dynamics in a heterostructure formed by trilayer WS2 and MoSe2 were investigated. The results show the occurrence of ultrafast interlayer charge transfer and intralayer valley scattering of the photocarriers. The band structures of few-layer transition metal dichalcogenides enable rich photocarrier dynamics.
JOURNAL OF MATERIALS CHEMISTRY C
(2022)
Article
Materials Science, Multidisciplinary
Peymon Zereshki, Pavel Valencia-Acuna, Hui Zhao
Summary: An all-optical approach to control interlayer charge transfer and interlayer exciton dynamics is demonstrated using transition metal dichalcogenide heterostructures of MoSe2/MoS2 and MoSe2/WS2 as examples. The study shows that the control pulse can influence the electron transfer time between layers and the dipole moment of interlayer excitons, providing tools for ultrafast manipulation of electrons in van der Waals heterostructures. Additionally, the control pulse enhances the recombination of interlayer excitons, increasing the spatial overlap of electron and hole wave functions.
