ADVANCED FUNCTIONAL MATERIALS
·
2023
·Vol. 33
·期 33
·2302199
·
IF 19
Zhao-Yang Yin,Yang Chen,Yang-Yang Zhang,Yu Yuan,Qian Yang,Ya-Nan Zhong,Xu Gao,Jing Xiao,Zhao-Kui Wang,Jian-Long Xu,Sui-Dong Wang
Minimizing reverse bias dark current density ( J dark ) while retaining high external quantum efficiency is crucial for promising applications of perovskite photodiodes, and it remains challenging to elucidate the ultimate origin of J dark . It is demonstrated in this study that the surface defects induced by iodine vacancies are the main cause of J dark in perovskite photodiodes. In a targeted way, the surface defects are thoroughly passivated through a simple treatment with butylamine hydroiodide to form ultrathin 2D perovskite on its 3D bulk. In the passivated perovskite photodiodes, J dark as low as 3.78 × 10 -10 A cm -2 at -0.1 V is achieved, and the photoresponse is also enhanced, especially at low light intensities. A combination of the two improvements realizes high specific detectivity up to 1.46 × 10 12 Jones in the devices. It is clarified that the trap states induced by the surface defects can not only raise the generation-recombination current density associated with the Shockley–Read–Hall mechanisms in the dark (increasing J dark ), but also provide additional carrier recombination paths under light illumination (decreasing photocurrent). The critical role of surface defects on J dark of perovskite photodiodes suggests that making trap-free perovskite thin films, for example, by fine preparation and/or surface engineering, is a top priority for high-performance perovskite photodiodes.
研究领域:
光电子学
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半导体器件物理
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材料科学
·
表面工程
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缺陷化学
·
光电探测器
✓ 已验证
DOI
高影响因子
Nanomaterials
·
2021
·Vol. 11
·期 5
·1253
·
IF 5.076
Xianwei Meng,Kailin Chi,Qian Li,Bingtao Feng,Haodi Wang,Tianjiao Gao,Pengyu Zhou,Haibin Yang,Wuyou Fu
In the process of preparing CsPbBr3films by two-step or multi-step methods, due to the low solubility of CsBr in organic solvents, the prepared perovskite films often have a large number of holes, which is definitely not conducive to the performance of CsPbBr3perovskite solar cells (PSCs). In response to this problem, this article proposed a method of introducing InBr3into the PbBr2precursor to prepare a porous PbBr2film to increase the reaction efficiency between CsBr and PbBr2and achieve the purpose of In (Ⅲ) incorporation, which not only optimized the morphology of the produced CsPbBr3film but also enhanced the charge extraction and transport capabilities, which was ascribed to the reduction of the trap state density and impurity phases in the perovskite films, improving the performance of CsPbBr3PSCs. At the optimal InBr3concentration of 0.21 M, the InBr3:CsPbBr3perovskite solar cell exhibited a power conversion efficiency of 6.48%, which was significantly higher than that of the pristine device.
研究领域:
材料科学
·
太阳能
·
光伏技术
✓ 已验证
DOI
高影响因子
Advanced Optical Materials
·
2025
·Vol. 13
·期 28
·e00362
·
IF 7.2
Wei Fu,Zelong Li,Yifan Ding,Maojie Zhang,Yong Cui,Hong Zhang,Xiaoliang Mo,Rongjun Zhang,Guangzheng Zuo
This study addresses the challenges of high dark current density and low responsivity in near-infrared organic photodetectors (NIR-OPDs) through a synergistic strategy combining morphology control and interface engineering. A thick active layer incorporating solid additives effectively reduces the dark current density while preserving efficient charge transport. Subsequently, molecular interface modification using [2-(9HCarbazol-9-yl)ethyl]phosphonic acid (2PACz) further suppresses the dark current and enhances photoresponsivity. Drift-diffusion modeling, incorporating trap states, reveals that the 2PACz forms a dipole layer at the interface, lowering the injection barrier by ≈0.3 eV and eliminating traps within the device. Together, these strategies reduce the dark current density from the order of 10 −5 A cm −2 (control) to the order of 10 −8 A cm −2 at −1 V, and enhance the responsivity ( R ) from 0.50 A W −1 (control) to 0.58 A W −1 at 864 nm. The resulting device exhibits a high shot-noise-limited specific detectivity ( D sℎ ∗ ) reaching 9.57 × 10 13 Jones, highlighting its exceptional sensitivity. This study demonstrates that combining morphology control with interface engineering effectively overcomes key performance limitations in NIR-OPDs, providing valuable insights for the design of high-performance organic photodetectors.
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产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2025
·
IF 8.2
Changchun Qi,Xiong Yang,Jiufeng Dong,Guangyu Sun,Wenrui Li,Fangzheng Zou,Ruitong Zhou,Xiaogang Qin,Baipeng Song,Guanjun Zhang
Polyimide (PI), a high-performance polymer widely employed in aerospace applications due to its superior electrical insulation, processability, and long-term stability, faces operational challenges at vacuum-solid interfaces. Under extreme space conditions, vacuum flashover phenomena frequently occur at PI interfaces during spacecraft operation, critically jeopardizing the reliability of the onboard electronic components. This study demonstrates a molecular engineering strategy to suppress secondary electron emission and improve surface insulation by modulating trap states through strong electron-withdrawing groups. Two all-organic specialty PI films were systematically developed via a strategic molecular structure design and subsequently fabricated. These films incorporate strong electron-withdrawing groups (e.g., −SO2– and −CF3), which effectively enhance trap densities and deepen trap levels, thereby suppressing the secondary electron multiplication process. Both specialty PI films demonstrated significantly enhanced vacuum surface flashover thresholds, with their vacuum flashover voltages Uho increased by 12.65 and 17.08% compared to pristine PI, respectively. The proposed molecular design paradigm provides a fundamental advancement in dielectric materials engineering, addressing the critical need for high-voltage tolerant insulation systems in next-generation spacecraft requiring elevated operational power and extended mission durations.
研究领域:
材料科学
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电气工程
·
高分子科学
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航空航天工程
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固体物理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MATERIALS RESEARCH BULLETIN
·
2022
·
IF 5.6
Lei Han,Xi Yuan,Zitong Wang,Jie Hua,Jin Wang,Jinju Zheng,Jialong Zhao
Mn-doped two-dimensional lead halide perovskites nanoplatelets (NPLs) possess promising application in solid state lighting. The Mn:L 2 [CsPbBr 3 ]PbBr 4 NPLs with corporation of Cd 2+ were prepared via a hot injection method. The photoluminescence (PL) properties the NPLs with different Mn/Pb/Cd molar ratio from 0.5/1/0 to 5/1/3 were investigated by steady-state and time-resolved PL spectroscopy, indicating that the doping efficiency of Mn 2+ can be boosted by adding Cd 2+ to the NPLs. After thermal annealing, the PL quantum yield of Mn 2+ ions reached up to 75%, which is Cd 2+ content dependent. The temperature-dependent PL spectra demonstrated that the thermal activation energies of the NPLs could be increased by incorporating Cd 2+ , meaning that the nonradiative defect/trap states were effectively suppressed. These experimental results suggested the PL properties of Mn:L 2 [CsPbBr 3 ]PbBr 4 NPLs were optimized by adding Cd 2+ ions.
研究领域:
材料科学
·
光电学
·
固态照明
✓ 已验证
DOI
高影响因子
Journal of Physical Chemistry Letters
·
2019
·
IF 7.329
Xin Liu,Yequan Xiao,Qiugui Zeng,Jiexuan Jiang,Yanbo Li
Organic-free perovskite solar cells (PSCs) have been considered as the most promising candidate for achieving long-term stability. Here, we demonstrate an organic-free PSC consisting of inorganic CsPbI2Br perovskite, nickel oxide hole transport layer, and niobium oxide electron transport layer. A maximum power conversion efficiency (PCE) of 11.20% is achieved with an active area of 5 cm2, and it increases to 14.11% with smaller area. More importantly, the organic-free PSCs show excellent thermal stability with PCE remaining above 98% of its initial value when heated at 100 °C for 150 min. Postannealing at a proper temperature further increases its maximum PCE to 14.45%, which is the highest among any reported all-inorganic PSCs with a p-i-n structure. The enhanced performance of the postannealed device is ascribed to the decreased trap-state density and improved interface charge-transfer properties. These results demonstrated that this novel organic-free device architecture can be employed to fabricate efficient and stable PSCs for large-scale manufacturing.
研究领域:
材料科学
·
可再生能源
·
应用物理
·
纳米技术
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry C
·
2025
·
IF 5.1
Shilin Liu,Jixi Zhou,Yijing Ding,Xianyu Zhao,Qing Li,Zhong Wu
Halide perovskites have emerged as highly promising materials for light absorption and emission, with significant potential in photovoltaics and optoelectronics. However, unintentional self-doping in solution-processed lead halide perovskite single crystals often degrades photodetector performance. In this study, we present an innovative precursor engineering approach aimed at controlling the self-doping characteristics of perovskite materials by optimizing the stoichiometry of the precursors. By precisely adjusting the PbCl2/MACl (MA = CH3NH3+) ratio, we achieved remarkable enhancements in MAPbCl3 single crystal performance. The crystal with a PbCl2/MACl molar ratio of 0.85 exhibited exceptional properties, including a high resistivity (2.7 × 108 Ω cm), outstanding carrier mobility (116.1 cm2 V−1 s−1), and ultralow trap state density (9.03 × 108 cm−3). Additionally, the fabricated MAPbCl3 single crystal ultraviolet photodetector (vertical architecture) demonstrated a high responsivity of 105 mA W−1 at 365 nm, with ultrafast response speed (rise time: 38.2 μs, fall time: 61.4 μs), surpassing all previously reported MAPbCl3 single crystal-based devices. These results highlight the superior quality of the optimized crystals, demonstrating their potential for use in high-performance optoelectronics and advancing perovskite integration into next-generation photonic and electronic technologies.
研究领域:
材料科学
·
光电子学
·
半导体物理
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纳米技术
·
光伏技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Hang Chen,Chao Liu,Ping Lin,Haihua Hu,Qingyu Meng,Lingbo Xu,Peng Wang,Xiaoping Wu,Can Cui
Organic hybrid CH 3 NH 3 PbBr 3 (MAPbBr 3 ) perovskite single crystal (SC) is popular in the field of photoelectric detection due to its outstanding photoelectric properties, but its performance is seriously limited by surface defects . Here, we report a surface passivation method to effectively reduce the surface defects by immersing MAPbBr 3 SC in an isopropanol (IPA) solution of CH 3 NH 3 Br (MABr). Compared to the untreated SC, the photoluminescence intensity of the homologous MABr treated SC is greatly enhanced by passivation treatment, and the photogenerated carrier lifetime increases from 16 ns to 148 ns. The space charge limited current (SCLC) results show that the trap state density is substantially reduced from 2.34 × 10 9 cm −3 to 7.22 × 10 8 cm −3 . The X-ray photoelectron spectrum (XPS) of the Pb element presents a significantly reduced peak of metalized Pb, confirming that the metalized Pb ion defects at the surface are effectively passivated. The asymmetry in current-voltage ( I - V ) curves arising from ion migration is substantially compressed. Furthermore, the photocurrent is significantly enhanced, and the responsivity and detectivity are ∼ 7 times higher in the MABr treated SC device. The results suggest a novel, feasible and efficient strategy to passivate surface defects for perovskite single crystals with improved properties.
研究领域:
材料科学
·
光电子学
·
表面化学
✓ 已验证
产品关联
DOI
高影响因子
Science China-Chemistry
·
2018
·Vol. 61
·期 4
·490-496
·
IF 4.448
Liu Zexi,Zou Hongyan,Wang Ni,Yang Tong,Peng Zhewei,Wang Jian,Li Na,Huang Chengzhi
Photoluminescence (PL) mechanism of carbon quantum dots (CQDs) remains controversial up to now even though a lot of approaches have been made. In order to do that, herein a PL color ladder from blue to near infrared of CQDs with the absolute quantum yields higher than 70% were prepared via a one-pot hydrothermal synthesis route and separated by silica gel column. Time-correlated single photon counting measurements suggest that the electron transition takes in effect in the PL progress of the crystalline core-shell structured CQDs, and the PL properties could be coarsely adjusted by tuning the size of the crystalline carbon core owing to quantum confinement effects, and finely adjusted by changing the surface functional groups consisted shell owing to surface trap states, respectively. Both coarse and fine adjustments of PL, as optical and photoelectrical characterizations and density-functional theory (DFT) calculations have demonstrated, make it possible for top-level design and precise synthesis of new CQDs with specific optical properties.
研究领域:
材料科学
·
纳米技术
·
光学
·
物理化学
✓ 已验证
DOI
高影响因子
Journal of Physical Chemistry C
·
2019
·
IF 4.309
Lin Guan,Nan Jiao,Yiping Guo
Trap-state passivation has been validated to efficiently improve the performance of perovskite solar cells. Small volatile molecules and polymers both have the ability to reduce the trap states in perovskite. Herein, we demonstrate the feasibility of passivation by nonvolatile small molecules with carboxylic acid groups such as benzoic acid, p-phthalic acid, and trimesic acid. They can obviously increase the fill factor of the photocurrent density–voltage curves. Furthermore, the relationship between the molecular structure and passivation effect is proposed by fixing the concentration of carboxylic acid groups. Trimesic-acid-doped perovskite solar cells significantly increase the power conversion efficiency from 12.52 ± 0.67 to 14.51 ± 0.81 (champion efficiency, 15.81%) under standard AM 1.5G illumination. Our work expands the chemical additives in perovskite and further demonstrates how the additive molecular structure influences the performance of solar cells.
研究领域:
材料科学
·
太阳能
·
光伏技术
✓ 已验证
产品关联
DOI
高影响因子
Advanced Optical Materials
·
2019
·Vol. 7
·期 10
·1801687
·
IF 7.125
Jialun Tang,Fei Li,Gaoling Yang,Yong Ge,Zhaohan Li,Zhiguo Xia,Huaibin Shen,Haizheng Zhong
Gradient-alloyed Cd x Zn 1− x Se y S 1− y @ZnS core shell quantum dots are the most popular materials used in light-emitting diodes for liquid crystal display backlights. High-temperature photoluminescence is an essential property in determining the chromaticity shifts of on-chip type devices. In this work, the photoluminescence quenching effect of Cd x Zn 1− x Se y S 1− y @ZnS quantum dots is investigated by measuring the steady and time-resolved PL spectra at elevated temperatures. The thermal quenching of Cd x Zn 1− x Se y S 1− y @ZnS quantum dots can be explained by a thermally activated physical process, including electron resonance tunneling into pre-existing surface trap states, injection over the barrier energy back to the core, and recombination with the confined holes. By combing the theoretical analysis and experimental results, the influence of core composition and shell thickness of Cd x Zn 1− x Se y S 1− y @ZnS QDs on the quenching effect is illustrated. It is found that the integrated photoluminescence intensity of ZnSe-rich quantum dots with 20 monolayers ZnS shell at 500 K can reserve 85.1%, relative to the value at 300 K. Quantum dots with enhanced photoluminescence emission at high temperature enable the fabrication of light-emitting diodes with reduced chromaticity shifts.
研究领域:
材料科学
·
光电技术
·
纳米技术
✓ 已验证
DOI
高影响因子
RSC Advances
·
2023
·Vol. 13
·期 4
·2411-2417
·
IF 3.9
Chenxin Xu,Lujie Liu,Yurong Huang,Fei Zhang,Hui Cao
Surface modification engineering is a well-known effective passivation method for making efficient and stable perovskite solar cells (PSCs). However, to our knowledge, little attention has been paid to simultaneously passivating the A and X sites of halogen perovskites. Herein, we introduced an organometallic salt (C6H5COO)2Mg (MgBEN) as a passivator, and as a result, the C6H5COOMg+ passivates the A site and C6H5COO− the X site on the perovskite layer, significantly reducing the trap-state density and nonradiative recombination. Moreover, the modification induces the perovskite film quality to improve, which may decrease the charge accumulation and facilitate carrier transport. By optimizing the concentration of the MgBEN, the perovskite film showed an increased grain size (from 1.18 μm to 1.61 μm), and the best device exhibited an enhanced power conversion efficiency (PCE) of 22.24%. Meanwhile, the device after modification performed with good long-term stability.
研究领域:
材料科学
·
光伏技术
·
化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）