EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
·
2020
·Vol. 2020
·期 10
·833-840
·
IF 2.529
Ruiping Wei,Jingdeng Fan,Xumin Qu,Lijing Gao,Yuanfeng Wu,Zongqi Zhang,Feng Hu,Guomin Xiao
Graphical Esterification of levulinic acid with ethanol was catalyzed by the cooperative effects between the Lewis acid sites offered by unsaturated Zr 6 nodes and Brønsted acid sites supplied by OH in defective UiO-66 MOFs with high defect density, which was tuned by precursor ratios and modulators. Due to their high stabilities and tunable defects, zirconium terephthalate UiO-66 type metal organic frameworks (MOFs) have been promising catalysts in many catalytic reactions. The catalytic activity of UiO-66 MOFs is significantly affected by the density of defects and hydroxyl groups bonded to Zr 6 nodes, which can be tuned by modulators. In this work, a series of defective UiO-66 were synthesized via tuning the ratio of H 2 BDC/Zr and adding monocarboxylic acids with different chain length as modulators. The synthesized UiO-66 MOFs were characterized by powder X-ray diffraction, N 2 physisorption, IR and 1 H NMR spectroscopy, scanning and transmission electron microscopy. Esterification of levulinic acid with ethanol was selected to reveal the influence of modulators, defects and hydroxyl groups. The results showed that UiO-66 with 0.5 of H 2 BDC/Zr ratio and lauric acid as the modulator owned excellent catalytic activity. The cooperative effects, between the Lewis acid sites offered by unsaturated Zr 6 nodes and Brønsted acid sites supplied by OH, has been revealed to have a significant influence on the catalytic activity.
研究领域:
材料化学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2024
·
IF 5.8
Jiaao Yu,Hui Luo,Zhihui Wang,Sihai Lv,Fu Chen,Yongzhi Cheng,Xiangcheng Li
Magnetic carbon-based aerogels with low-density and strong attenuation, have attracted significant attention as microwave absorbing materials, but still face huge challenges. Herein, magnetic FeMnC modified carbon/Graphene aerogels (NCMF) were synthesized utilizing freeze casting following a carbothermal reduction process. The conductivity, defects density , material component and electromagnetic properties can be regulated by the temperature. The NCMF aerogels exhibit remarkable microwave absorption properties, with an effective absorption bandwidth of 5.76 GHz at a thickness of 2.1 mm and a minimum reflection loss as low as −50.8 dB at 7.52 GHz with a fill ratio of only 5 wt%. The exceptional microwave absorption capabilities of NCMF aerogels are attributed to the synergistic effects of dielectric loss , magnetic loss, three-dimensional (3D) carbon conductive network, and the optimal impedance matching. Consequently, this research paves a way for the development of microwave absorbing materials with lightweight, broadband and strong microwave absorption at low loading.
研究领域:
材料科学
·
物理学
✓ 已验证
产品关联
DOI
高影响因子
Nanomaterials
·
2024
·Vol. 14
·期 20
·1651
·
IF 4.4
Qi Yu,Wentian Sun,Shu Tang
CsPbIBr2, with its suitable bandgap, shows great potential as the top cell in tandem solar cells. Nonetheless, its further development is hindered by a high defect density, severe carrier recombination, and poor stability. In this study, CsPbI1.5Br1.5quantum dots were utilized as an additive in the ethyl acetate anti-solvent, while a layer of CsPbBr3QDs was introduced between the ETL and the CsPbIBr2light-harvester film. The combined effect of these two QDs enhanced the nucleation, crystallization, and growth of CsPbIBr2perovskite, yielding high-quality films characterized by an enlarged crystal size, reduced grain boundaries, and smooth surfaces. And a wider absorption range and better energy band alignment were achieved owing to the nano-size effect of QDs. These improvements led to a decreased defect density and the suppression of non-radiative recombination. Additionally, the presence of long-chain organic molecules in the QD solution promoted the formation of a hydrophobic surface, significantly enhancing the long-term stability of CsPbIBr2PSCs. Consequently, the devices achieved a PCE of 9.20% and maintained an initial efficiency of 85% after 60 days of storage in air. Thus, this strategy proves to be an effective approach for the preparation of efficient and stable CsPbIBr2PSCs.
研究领域:
材料科学
·
能源科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF PHYSICS D-APPLIED PHYSICS
·
2025
·Vol. 58
·期 23
·235101
·
IF 3.2
Longhui Lei,Wenbo Cao,Jiajin Kuang,Chaofan Zheng,Mingtai Wang
A systematic investigation is conducted to determine the role of thiourea in regulating crystallization and defect formation in solution-processed CuInS2 solar cells. By modulating the Cu:In:S stoichiometry (1:1:6–1:1:10), sulfur content is found to critically influence material properties. The optimal stoichiometry (1:1:8) balances the defects density, stabilizes the chalcopyrite phase, and suppresses deleterious secondary phases, yielding a peak efficiency of 5.16% (Voc = 0.68 V, Jsc = 11.91 mA cm−2, FF = 63.52%). Excessive thiourea (1:1:10) induces defects (InCu) and (Ini), degrading device performance. These findings establish a dual mechanism for thiourea's role in solar cell performance: regulating defects concentration and crystal phase composition, providing a theoretical guide for solution-processed CuInS2 devices.
研究领域:
材料科学
·
能源技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Junjie Yan,Heng Zheng,Haojun Luo,Kaitong Xie,Zhifei Zhou,Xuanjie Huang,Xuanrui Zhang,Yuanzheng Yang,Yanxue Wu,Weitong Cai
CsPbBr₃ perovskite solar cells have attracted significant attention due to their outstanding stability and ease of fabrication. However, challenges remain regarding the uniformity of film crystallization and efficiency of the devices, which necessitate further improvements. Antisolvent washing is an effective approach to enhance the crystallization quality of perovskite films. In this study, we present an optimized antisolvent rinsing strategy utilizing a multi-step spin-coating method for the fabrication of CsPbBr₃ films. In the mixed antisolvent of ethyl acetate (EA) and ethanol (EtOH), increasing the volume ratio of EtOH results in a decrease in the number of pinhole defects in CsPbBr₃ films, as well as an increase in the average grain size. When the volume ratio of EA to EtOH is set at 8:2, the average grain size attains an optimal value of 648 nm. Devices based on the FTO/c-TiO₂/m-TiO₂/CsPbBr₃/carbon structure treated with the EA:EtOH (8:2) mixed antisolvent achieved a maximum power conversion efficiency (PCE) of 7.22%. The improvement in device efficiency is primarily attributed to enhanced charge transport and reduced defect density, which collectively suppress non-radiative recombination. Additionally, after 720 hours of storage in ambient air with 40-50% relative humidity, the devices retained 93% of their initial efficiency. This work provides valuable insights into the development of highly efficient and stable CsPbBr₃ perovskite solar cells.
研究领域:
材料科学
·
能源技术
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Nano Materials
·
2024
·
IF 5.3
Qiaocan Huang,Zunxian Yang,Yuliang Ye,Zongyi Meng,Zhiwei Zeng,Hongyi Hong,Songwei Ye,Zhiming Cheng,Qianting Lan,Bingqing Ye,Yuanqing Zhou,Zihong Shen,Wenbo Wu,Jiaxiang Wang,Ye Chen,Hui Zhang,Tailiang Guo,Fushan Li,Yongyi Chen,Zhenzhen Weng
Cadmium selenide (CdSe)-based colloidal quantum dots (QDs) exhibit unique properties such as tunable colors, narrow emission, high photoluminescence efficiency, and high stability, making them one of the most promising candidates for next-generation displays. CdSe-based QD light-emitting diodes (QLEDs) have attracted more and more attention mainly due to their advantages including high electroluminescence brightness, low turn-on voltage, and ultrathin device structures. However, there are still many challenges, mainly including the lattice defects aroused by lattice strain during the QD growth process and the surface defects caused by ligand desorption. CdSe-based QLEDs with high photoelectronic performance were finally achieved in our work just by optimizing the synthesis processes and further reducing defects in QD shells. There was a great decrease in the defect density of the QD shell indirectly according to their testing results in the fluorescence lifetime and single-carrier devices. After the reaction system was diluted with a solvent in the hot-injection method, there was some blue shift in the QD emission observed from 595 to 562 nm. Then, with the ZnSe shell further coated onto the QD, the size of the effective emission center was reduced to some extent, and further, a blue shift in the emission was obtained with the wavelength down to 533 nm. Finally, on the outside of the as-synthesized QDs, the ZnS shell was used to passivate and further protect the ZnSe layer, which greatly increased the average fluorescence lifetime of the CdSe-based QDs from 22.94 to 36.41 ns. Additionally, a layer of lithium fluoride (LiF) with optimized thickness was further deposited onto the QD emitting layer to prevent ligand desorption from ethanol solvent cleaning. Therefore, the CdSe-based QD fluorescence efficiency was greatly improved and the maximum external quantum efficiency (EQE) of 8.06% for our CdSe-based QLEDs was achieved with a LiF layer of 3 nm.
研究领域:
材料科学
·
光电工程
✓ 已验证
产品关联
DOI
高影响因子
Advanced Materials Interfaces
·
2022
·Vol. 10
·期 6
·2202159
·
IF 6.389
Xiao Liu,Yu Jing,Chunyan Wang,Xin Wang,Ruoshui Li,Yuan Xu,Zhongliang Yan,Huayan Zhang,Jihuai Wu,Zhang Lan
Perovskite silicon tandem solar cells are one of the effective ways to further improve the photoelectric conversion efficiency (PCE) in the research and development of solar cells in the future. CsPbIBr 2 can be used as the top cell material in tandem solar cells due to its wider bandgap and better long-term stability. However, the serious defect density and carrier recombination limit its further improvement. In this work, Octylammonium Octyldithiocarbamate (ODTC) is added to the CsPbIBr 2 precursor. Through its strong metal ion complexing ability, it combines with the uncoordinated Pb 2+ in the CsPbIBr 2 , and then thermally decomposes to produce PbS during the annealing process. As an additive, ODTC modulates the crystallization of CsPbIBr 2 , increases the crystal size, reduces defect density, extends carrier lifetime, and improves charge transfer. Moreover, in situ-generated PbS can also optimize photovoltaic performance of CsPbIBr 2 perovskite solar cell (PSC). Consequently, the champion PCE of the devices can attain to 10.15% and still maintain an initial efficiency of 90% after 45 days. Therefore, the strategy is an effective way to prepare efficient and stable CsPbIBr 2 PSCs.
研究领域:
材料科学
·
光伏技术
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Small Methods
·
2023
·Vol. 7
·期 4
·2201663
·
IF 12.4
Siyuan Lin,Shuyue Wu,De'en Guo,Han Huang,Xuefan Zhou,Dou Zhang,Kechao Zhou,Wenhao Zhang,Yue Hu,Yongli Gao,Conghua Zhou
Fast reaction between organic salt and lead iodide always leads to small perovskite crystallites and concentrated defects. Here, polyacrylic acid is blended with organic salt, so as to regulate the crystallization in a two-step growth method. It is observed that addition of polyacrylic acid retards aggregation and crystallization behavior of the organic salt, and slows down the reaction rate between organic salt and PbI 2 , by which “slow-release effect” is defined. Such effect improves crystallization of perovskite. X-ray diffraction study shows that, after addition of 2 m m polyacrylic acid, average crystallite size of perovskite increases from ≈40 to ≈90 nm, meanwhile, grain size increases. Thermal admittance spectroscopy study shows that trap density is reduced by nearly one order (especially for deep energy levels). Due to the improved crystallization and reduced trap density, charge recombination is obviously reduced, while lifetime of charge carriers in perovskite film and devices are prolonged, according to time-resolved photoluminescence and transient photo-voltage decay curve tests, respectively. Accordingly, power conversion efficiency of the device is promoted from 19.96 (±0.41)% to 21.84 (±0.25)% (with a champion efficiency of 22.31%), and further elevated to 24.19% after surface modification by octylammonium iodide.
研究领域:
材料科学
·
光伏技术
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Omega
·
2023
·
IF 4.1
Pengpeng Cheng,Zehan Liu,Ruyan Kang,Jian Zhou,Xiaoshan Wang,Jia Zhao,Zhiyuan Zuo
Organic–inorganic hybrid perovskites have demonstrated exceptional photovoltaic properties, making them highly promising for solar cells and photodetectors (PDs). However, the organic components of these materials are vulnerable to heat and strong light illumination, limiting their application prospects. All-inorganic cesium-based perovskite PDs, on the other hand, possess enhanced thermal tolerance and stability, making them ideal for perovskite applications. The utilization of a ternary mixture solvent and additives in combination with single crystal (SC) growth has enabled the production of highly crystalline SCs with a defect density of 3.79 × 109 cm–3. The performance of the SC PDs had been evaluated using metal–semiconductor–metal devices, which demonstrated excellent results with a dark current as low as 0.198 μA at 10 V bias, on–off ratios exceeding 103, and a response time of shorter than 1 ms.
研究领域:
材料科学
·
光电技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Physica Status Solidi-Rapid Research Letters
·
2023
·
IF 2.8
Anfeng Li,Manman Yang,Aoxi He,Peng Tang,Xia Hao,Lili Wu,Wenbo Tian,Dingyu Yang,Jingquan Zhang
Cs 3 Bi 2 I 9 (CBI) is a promising material for direct X-ray detectors. However, for the solution method, due to the difference in the chemical potential of Cs + , Bi 3+ , I − ions in the solvent, the composition of CBI single crystals (SCs) prepared by the solution method often deviates from the stoichiometric ratio, resulting in the formation of many defects in the material, which degrades the quality of the SC. Herein, Br − and Cl − are used as dopants to produce CBI SCs by the top seed solution method. It can be speculated that the dopant ions can reduce the V I defects in the CBI by means of density functional theory calculations. The carrier lifetimes of CBI SCs doped with Br − and Cl − have been increased to 41.7 and 13.0 ns, respectively. Meanwhile, the defect densities of the SCs are reduced to 1.02 × 10 9 and 1.85 × 10 9 cm −3 , respectively. X-ray detectors based on Br-doped CBI and Cl-doped CBI SCs exhibit high X-ray sensitivity of 23071.3 and 18525.3 μC Gy air −1 cm −2 at an electric field of 40 V mm −1 , respectively. In addition, the X-ray detection limit reaches 1.07 and 1.35 nGy air s −1 at an electric field of 2.5 V mm −1 , respectively.
研究领域:
材料科学
·
物理学
✓ 已验证
产品关联
DOI
高影响因子
Light-Science & Applications
·
2020
·Vol. 9
·期 1
·1-11
·
IF 13.714
Xing Jun,Zhao Chen,Zou Yuting,Kong Wenchi,Yu Zhi,Shan Yuwei,Dong Qingfeng,Zhou Ding,Yu Weili,Guo Chunlei
Defect density is one of the most significant characteristics of perovskite single crystals (PSCs) that determines their optical and electrical properties, but few strategies are available to tune this property. Here, we demonstrate that voltage regulation is an efficient method to tune defect density, as well as the optical and electrical properties of PSCs. A three-step carrier transport model of MAPbBr 3 PSCs is proposed to explore the defect regulation mechanism and carrier transport dynamics via an applied bias. Dynamic and steady-state photoluminescence measurements subsequently show that the surface defect density, average carrier lifetime, and photoluminescence intensity can be efficiently tuned by the applied bias. In particular, when the regulation voltage is 20 V (electrical poling intensity is 0.167 V μm −1 ), the surface defect density of MAPbBr 3 PSCs is reduced by 24.27%, the carrier lifetime is prolonged by 32.04%, and the PL intensity is increased by 112.96%. Furthermore, a voltage-regulated MAPbBr 3 PSC memristor device shows an adjustable multiresistance, weak ion migration effect and greatly enhanced device stability. Voltage regulation is a promising engineering technique for developing advanced perovskite optoelectronic devices.
研究领域:
材料科学
·
光学工程
·
电子工程
✓ 已验证
DOI
高影响因子
Journal of Energy Chemistry
·
2025
·
IF 14.9
Zhongyu Liu,Xiu Huang,Yuchen Zhao,Jianwei Wang,Jiaying Liu,Chenyu Zhou,Hongwei Wang,Tian Cui,Xiaohui Liu
Inorganic CsPbI 3 perovskite with superior thermal stability and photoelectric properties has developed into a promising candidate for photovoltaic applications. Nevertheless, the power conversion efficiency (PCE) of CsPbI 3 perovskite solar cells (PSCs) still lags far behind that of both organic-inorganic hybrid counterparts and the theoretical PCE limit, primarily restricted by severe fill factor (FF) and open-circuit voltage ( V OC ) deficits. Herein, an in-situ self-crosslinking strategy is proposed to construct high-performance inverted inorganic PSCs by incorporating acrylate monomers as additives into CsPbI 3 perovskite precursors. During the thermal annealing process of perovskite films, acrylate monomers can form network structures by breaking the C=C groups through an in-situ polymerization reaction, mainly anchored at the grain boundaries (GBs) and on the surfaces of perovskite. Meanwhile, the C=O groups of acrylate polymers can favorably coordinate with uncoordinated Pb 2+ , thereby decreasing defect density and stabilizing the perovskite phase. Particularly, with multiple crosslinking and passivation sites, the incorporation of dipentaerythritol pentaacrylate (DPHA) can effectively improve the perovskite film quality, suppress nonradiative recombination, and block moisture erosion. Consequently, the DPHA-based PSC achieves a champion PCE of 20.05% with a record-high FF of 85.05%, both of which rank among the top in the performance of inverted CsPbI 3 PSCs. Moreover, the unencapsulated DPHA-based device exhibits negligible hysteresis, remarkably improved long-term storage, and operational stability. This work offers a facile and useful strategy to simultaneously promote the efficiency and device stability of inverted inorganic PSCs.
研究领域:
材料科学
·
光伏技术
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）