Surface Passivation by Congeneric Quantum Dots for High-Performance and Stable CsPbBr3-Based Photodetectors

2021 ◽  
Author(s):  
Shikai Yan ◽  
Sheng Tang ◽  
Manman Luo ◽  
Lu Xue ◽  
Shilin Liu ◽  
...  
Keyword(s):  
Quantum Dots ◽  
High Performance ◽  
Surface Passivation ◽  
Low Cost ◽  
Optoelectronic Properties ◽  
Solution Processing

CsPbBr3-based photodetectors (PDs) have aroused enormous attention owing to their low-cost solution processing, outstanding optoelectronic properties, and remarkable stability. However, their performances remain a big challenge to meet the requirement...

scholarly journals Simultaneously Regulating Uniform Zn2+ Flux and Electron Conduction by MOF/rGO Interlayers for High-Performance Zn Anodes

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Ziqi Wang ◽  
Liubing Dong ◽  
Weiyuan Huang ◽  
Hao Jia ◽  
Qinghe Zhao ◽  
...  
Keyword(s):  
High Performance ◽  
Surface Passivation ◽  
Coulombic Efficiency ◽  
Low Cost ◽  
Metal Organic Framework ◽  
Growth Surface ◽  
Electron Conduction ◽  
Reduced Graphene ◽  
Metal Organic ◽  
Further Development

AbstractOwing to the merits of low cost, high safety and environmental benignity, rechargeable aqueous Zn-based batteries (ZBs) have gained tremendous attention in recent years. Nevertheless, the poor reversibility of Zn anodes that originates from dendrite growth, surface passivation and corrosion, severely hinders the further development of ZBs. To tackle these issues, here we report a Janus separator based on a Zn-ion conductive metal–organic framework (MOF) and reduced graphene oxide (rGO), which is able to regulate uniform Zn2+ flux and electron conduction simultaneously during battery operation. Facilitated by the MOF/rGO bifunctional interlayers, the Zn anodes demonstrate stable plating/stripping behavior (over 500 h at 1 mA cm−2), high Coulombic efficiency (99.2% at 2 mA cm−2 after 100 cycles) and reduced redox barrier. Moreover, it is also found that the Zn corrosion can be effectively retarded through diminishing the potential discrepancy on Zn surface. Such a separator engineering also saliently promotes the overall performance of Zn|MnO2 full cells, which deliver nearly 100% capacity retention after 2000 cycles at 4 A g−1 and high power density over 10 kW kg−1. This work provides a feasible route to the high-performance Zn anodes for ZBs.

scholarly journals Tuning Carbon Dots’ Optoelectronic Properties with Polymers

Polymers ◽  
2018 ◽  
Vol 10 (12) ◽  
pp. 1312 ◽  
Author(s):  
Konstantinos Dimos
Keyword(s):  
Quantum Yield ◽  
Spectral Range ◽  
Carbon Dots ◽  
Surface Passivation ◽  
Low Cost ◽  
Quality Characteristics ◽  
Optoelectronic Properties ◽  
Quantum Yields

Due to their unique properties of photoluminescence, biocompatibility, photostability, ease of preparing, and low cost, carbon dots have been studied extensively over the last decade. Soon after their discovery, it was realized that their main optical attributes may be protected, enhanced, and tuned upon proper surface passivation or functionalization. Therefore, up to date, numerous polymers have been used for these purposes, resulting to higher-quality carbon dots regarding their quantum yield or further emission-related aspects and compared to the primitive, bare ones. Hence, this review aims to clarify the polymers’ role and effect on carbon dots and their features focusing on the quality characteristics of their photoluminescence upon passivation or functionalization. Given in fact the numbers of relevant publications, emphasis is given on recent articles capturing the latest advances for polymers in carbon dots for expanding emission lifetimes, advancing quantum yields, tuning emission wavelengths, enhancing specific spectral range absorption, and tailoring optoelectronic properties in general.

Defects and passivation in perovskite solar cells

2021 ◽  
pp. 1-18
Author(s):  
Yaobo Li ◽  
Zhaohan Li ◽  
Fangze Liu ◽  
Jing Wei
Keyword(s):  
Solar Cells ◽  
High Performance ◽  
Surface Passivation ◽  
Low Cost ◽  
Perovskite Solar Cells ◽  
Film Deposition ◽  
Transport Layer ◽  
Hybrid Perovskite ◽  
High Absorption Coefficient ◽  
Charge Transport Layer

This organic-inorganic hybrid perovskite materials have attracted great attention by virtue of their high absorption coefficient, low cost and simple film deposition technique. Based on these advantages, perovskite solar cells have reached an impressive power conversion efficiency over 25%. However, the low-temperature process inevitably leads to a large number of defects in the perovskite film. These defects would exacerbate the carrier recombination, induce crystal degradation, phase transformation and seriously affect the performance of devices. Studying the defects in perovskite film is of great significance for the development of high-performance perovskite solar cells. Herein, the authors summarise the causes, distribution and features of defects, as well as their effects on the performance of perovskite solar cells. Furthermore, some defect-passivation strategies on perovskite film or the device, including grain boundary passivation, surface passivation, capping layer modification and charge transport layer passivation, are discussed, respectively. Lastly, some remaining challenges in the commercialisation of perovskite solar cells are proposed.

scholarly journals A Novel Phototransistor Device with Dual Active Layers Composited of CsPbBr3 and ZnO Quantum Dots

Materials ◽  
2019 ◽  
Vol 12 (8) ◽  
pp. 1215 ◽  
Author(s):  
Xu Zhang ◽  
Qing Li ◽  
Shikai Yan ◽  
Wei Lei ◽  
Jing Chen ◽  
...  
Keyword(s):  
Quantum Dots ◽  
High Performance ◽  
Low Cost ◽  
Conducting Layer ◽  
Light Illumination ◽  
High Electron ◽  
Zno Film ◽  
Active Layers ◽  
Zno Qds ◽  
Photodetector Device

Taking advantage of a large light absorption coefficient, long charge carrier diffusion length and low-cost solution processing, all-inorganic halides perovskite CsPbBr3 quantum dots (QDs) are combined with a ZnO QD film to construct a high-performance photodetector. In this work, a novel photodetector device based on transistor structure with dual active layers composed of CsPbBr3 and ZnO film is proposed. In this structure, CsPbBr3 film functions as the light-absorbing layer and ZnO film acts as the conducting layer. Owing to the high electron mobility and hole-blocking nature of the ZnO QDs film, the photo-induced electron-hole pairs can be separated efficiently. As a result, the device exhibits high performance with response of 43.5 A/W, high detection up to 5.02 × 1011 Jones and on/off ratio of 5.6 × 104 under 365 nm light illumination. Compared with the ZnO-only phototransistor (the photodetector with the structure of transistor) the performance of the CsPbBr3 phototransistor showed significant improvement, which is superior to the majority of photodetectors prepared by perovskite. This work demonstrates that the ZnO QDs film can be applied in the photodetector device as a functional conducting layer, and we believe that the hybrid CsPbBr3/ZnO phototransistor would promote the development of low-cost and high-performance photodetectors.

Low cost and large scale synthesis of PbS quantum dots with hybrid surface passivation

CrystEngComm ◽  
2017 ◽  
Vol 19 (6) ◽  
pp. 946-951 ◽  
Author(s):  
Zhen Huang ◽  
Guangmei Zhai ◽  
Zhiming Zhang ◽  
Changwang Zhang ◽  
Yong Xia ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Large Scale ◽  
Surface Passivation ◽  
Low Cost ◽  
Large Scale Synthesis ◽  
Pbs Quantum Dots

scholarly journals Ecofriendly Water-Based Solution Processing: Preliminary Studies of Zn-ZrO2 Thin Films for Microelectronics Applications

Coatings ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 901
Author(s):  
Aneeqa Bashir ◽  
Hina Siddiqui ◽  
Shahzad Naseem ◽  
Arshad Saleem Bhatti
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
High Performance ◽  
Low Cost ◽  
High Yield ◽  
Structural Quality ◽  
Solution Processing ◽  
Performance Targets ◽  
Glass Substrates ◽  
Water Based

This paper demonstrates the high yield and cost effectiveness of a simple and ecofriendly water-based solution processing, to produce Zinc-doped Zirconia (Zn-ZrO2) composite thin films, onto glass substrates, with excellent optical properties that make them of great interest for optical and microelectronics technologies. The effect of Zn variation (given as 10, 15, 20 at.%) on the crystallization, microstructure, and optical properties of ZrO2 film was examined. The addition of Zn did not restructure the ZrO2 lattice, as the results indicated by X-ray diffraction (XRD) and Raman spectroscopy revealed neither any mixed or individual phases; rather, all the films retained the amorphousness. Nonetheless, Zn did control the grain formation at the film surfaces, thereby changing the surface morphology. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) evidenced homogeneous, compact, crack-free, and dense films with surface roughness below 2 nm indicating smooth surfaces. The films were highly transparent (>80%) with tunable optical band gap Eg (5.21 to 4.66 eV) influenced by Zn dopant. Optical constants such as refractive index (n), extinction coefficient (k), and dielectric constant (ε) were obtained from spectroscopic ellipsometry (SE), and a correlation was established with respect to the doping level. A high value of n > 2 value indicated high packing density in these films, and it decreased slightly from 2.98 to 2.60 (at 632 nm); whereas, optical losses were brought down with increasing Zn indicated by decreasing k values. The photoluminescence (PL) spectra showed UV emissions more pronounced than the blue emissions indicating good structural quality of all the films. Nonetheless, added defects from Zn had suppressed the PL emission. The technique presented in this work, thus, manifests as high performance and robust and has the potential comparable to the sophisticated counter techniques. Furthermore, the Zn-ZrO2 films are promising for a low-cost solution to processed microelectronics and optical technologies after reaching high performance targets with regards to the electrical properties.

scholarly journals Effect of CdS/Mg-Doped CdSe Cosensitized Photoanode on Quantum Dot Solar Cells

2015 ◽  
Vol 2015 ◽  
pp. 1-6
Author(s):  
Yingxiang Guan ◽  
Xiaoping Zou ◽  
Sheng He
Keyword(s):  
Quantum Dots ◽  
Solar Cells ◽  
Quantum Dot ◽  
High Performance ◽  
Low Cost ◽  
Energy Conversion Efficiency ◽  
Cdse Qds ◽  
Cdse Quantum Dot ◽  
Sensitized Solar Cells ◽  
Mg Doped

Quantum dots have emerged as a material platform for low-cost high-performance sensitized solar cells. And doping is an effective method to improve the performance of quantum dot sensitized solar cells (QDSSCs). Since Kwak et al. from South Korea proved the incorporation of Mg in the CdSe quantum dots (QDs) in 2007, the Mg-doped CdSe QDs have been thoroughly studied. Here we report a new attempt on CdS/Mg-doped CdSe quantum dot cosensitized solar cells (QDCSSC). We analyzed the performance of CdS/Mg-doped CdSe quantum dot cosensitized solar cells via discussing the different doping concentration of Mg and the different SILAR cycles of CdS. And we studied the mechanism of CdS/Mg-doped CdSe QDs in detail for the reason why the energy conversion efficiency had been promoted. It is a significant instruction on the development of Mg-doped CdSe quantum dot sensitized solar cells (QDSSCs).

scholarly journals MoS2 Nanosheets Sensitized with Quantum Dots for Room-Temperature Gas Sensors

2020 ◽  
Vol 12 (1) ◽  
Author(s):  
Jingyao Liu ◽  
Zhixiang Hu ◽  
Yuzhu Zhang ◽  
Hua-Yao Li ◽  
Naibo Gao ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Gas Sensors ◽  
High Performance ◽  
Large Scale ◽  
Room Temperature ◽  
Gas Sensing ◽  
Low Cost ◽  
Surface And Interface ◽  
Sensor Performance ◽  
Semiconductor Gas Sensors

AbstractThe Internet of things for environment monitoring requires high performance with low power-consumption gas sensors which could be easily integrated into large-scale sensor network. While semiconductor gas sensors have many advantages such as excellent sensitivity and low cost, their application is limited by their high operating temperature. Two-dimensional (2D) layered materials, typically molybdenum disulfide (MoS2) nanosheets, are emerging as promising gas-sensing materials candidates owing to their abundant edge sites and high in-plane carrier mobility. This work aims to overcome the sluggish and weak response as well as incomplete recovery of MoS2 gas sensors at room temperature by sensitizing MoS2 nanosheets with PbS quantum dots (QDs). The huge amount of surface dangling bonds of QDs enables them to be ideal receptors for gas molecules. The sensitized MoS2 gas sensor exhibited fast and recoverable response when operated at room temperature, and the limit of NO2 detection was estimated to be 94 ppb. The strategy of sensitizing 2D nanosheets with sensitive QD receptors may enhance receptor and transducer functions as well as the utility factor that determine the sensor performance, offering a powerful new degree of freedom to the surface and interface engineering of semiconductor gas sensors.

Constructing High-performance H3PW12O40/CoS2 Counter Electrodes for Quantum Dots Sensitized Solar Cells by Reducing the Surface Work Function of CoS2

2021 ◽  
Author(s):  
Tingting Zhang ◽  
Qiu Zhang ◽  
Yumeng Wang ◽  
Fengyan Li ◽  
Lin Xu
Keyword(s):  
Quantum Dots ◽  
Solar Cells ◽  
Work Function ◽  
High Performance ◽  
Counter Electrode ◽  
Low Cost ◽  
Counter Electrodes ◽  
Surface Work ◽  
Sensitized Solar Cells ◽  
Surface Work Function

The preparation of low cost H3PW12O40 (PW12)/CoS2 complex is used as a counter electrode (CE) to combine with sandwich quantum dots sensitized cells (QDSSCs) composed of TiO2/CdS/CdSe/ZnS photoanode and polysulfide...

scholarly journals Graphene on Silicon Photonics: Light Modulation and Detection for Cutting-Edge Communication Technologies

2021 ◽  
Vol 12 (1) ◽  
pp. 313
Author(s):  
Siqi Yan ◽  
Jeremy Adcock ◽  
Yunhong Ding
Keyword(s):  
Silicon Photonics ◽  
Communication Systems ◽  
High Performance ◽  
Low Cost ◽  
Single Layer ◽  
Photonic Devices ◽  
Optoelectronic Properties ◽  
Propagation Loss ◽  
Honeycomb Lattice ◽  
Light Modulation

Graphene—a two-dimensional allotrope of carbon in a single-layer honeycomb lattice nanostructure—has several distinctive optoelectronic properties that are highly desirable in advanced optical communication systems. Meanwhile, silicon photonics is a promising solution for the next-generation integrated photonics, owing to its low cost, low propagation loss and compatibility with CMOS fabrication processes. Unfortunately, silicon’s photodetection responsivity and operation bandwidth are intrinsically limited by its material characteristics. Graphene, with its extraordinary optoelectronic properties has been widely applied in silicon photonics to break this performance bottleneck, with significant progress reported. In this review, we focus on the application of graphene in high-performance silicon photonic devices, including modulators and photodetectors. Moreover, we explore the trend of development and discuss the future challenges of silicon-graphene hybrid photonic devices.

Sign in / Sign up

Export Citation Format

Share Document