ACS Applied Materials & Interfaces
·
2021
·
IF 9.229
Jie Zhang,Kaiyu Wang,Qing Yao,Ye Yuan,Jianxu Ding,Weiwei Zhang,Haiqing Sun,Chenyu Shang,Changqian Li,Tianliang Zhou,Shuping Pang
MAPbI3, one of the archetypical metal halide perovskites, is an exciting semiconductor for a variety of optoelectronic applications. The photoexcited charge-carrier diffusion and recombination are important metrics in optoelectronic devices. Defects in grain interiors and boundaries of MAPbI3 films cause significant nonradiative recombination energy losses. Besides defect impact, carrier diffusion and recombination anisotropy introduced by structural and electronic discrepancies related to the crystal orientation are vital topics. Here, large-sized MAPbI3 single crystals (SCs) were grown, with the (110), (112), (100), and (001) crystal planes simultaneously exposed through the adjusting ratios of PbI2 to methylammonium iodide (MAI). Such MAPbI3 SCs exhibit a weak n-type semiconductor character, and the Fermi levels of these planes were slightly different, causing a homophylic p–n junction at crystal ledges. Utilizing MAPbI3 SCs, the photoexcited carrier diffusion and recombination within the crystal planes and around the crystal ledges were investigated through time-resolved fluorescence microscope. It is revealed that both the (110) and (001) planes were facilitated to be exposed with more MAI in the growth solutions, and the photoluminescence (PL) of these planes manifesting a red-shift, longer carrier lifetime, and diffusion length compared with the (100) and (112) planes. A longer carrier diffusion length promoted photorecycling. However, excessive MAI-assisted grown MAPbI3 SCs could increase the radiative recombination. In addition, it revealed that the carrier excited within the (001) and (112) planes was inclined to diffuse toward each other and was favorable to be extracted out of the grain boundaries or crystal ledges.
研究领域:
材料科学
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光学
·
半导体物理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Energy Materials
·
2020
·
IF 4.473
Jianxu Ding,Lin Jing,Ye Yuan,Jie Zhang,Qing Yao,Kaiyu Wang,Weiwei Zhang,Haiqing Sun,Bing Liu,Tianliang Zhou,Xiaoyuan Zhan
The optoelectronic performances of MAPbI3 are related to film morphology and crystal orientation. However, it is difficult to directly quantify the optoelectronic anisotropy in thin films because controlling growth-oriented grains and measuring the optoelectronic difference within micro–nono regions have great technological challenges. Here, taking advantages of the pseudo-cubic morphology of MAPbI3 single crystals (SCs) exposed with (110), (002), and (200) facets, the optoelectronic anisotropies are compared. It reveals that the periodic positive and negative potential distributions at the outermost (110) surface, the orientations of MA+ dipoles, and the stacking of PbI6 octahedrons ensure (110) planes have lower defect densities (VI+, VMA–, I–, MA+, or Ii–, etc.), which therefore enhance photo recycling, deduce the dark current, and increase the photocurrent. Besides, the periodic MA+ and I– arrangements at the (110) surface also restrict ion migrations compared to those of (200) planes. In addition, by comparing the optoelectronic properties of (200) planes of the pseudo-cubic and rhombic dodecahedral MAPbI3 SCs, it is found that the room-temperature-grown pseudo-cubic MAPbI3 SC possesses lower intrinsic defect densities and thus enhances the photo response.
研究领域:
材料科学
·
光电材料
✓ 已验证
DOI
高影响因子
Frontiers in Materials
·
2021
·
IF 3.515
Xu Yubing,Wang Xin,Zhao Jingda,Pan Yuzhu,Li Yuwei,Elemike Elias Emeka,Li Qing,Zhang Xiaobing,Chen Jing,Zhao Zhiwei,Akram Javed,Bae Byung Seong,Bin Suhaidi,Lei Wei
Recent years, organic-inorganic hybrid perovskites (OIHPs) have been widely used in applications, such as solar cells, lasers, light-emission diodes, and photodetectors due to their outstanding optoelectronic properties. Nowadays photodetectors based on perovskite films (PFs) suffer from surface and interface traps, which result from low crystalline quality of perovskite films and lattice mismatch between perovskite films and substrates. Herein, we fabricate MAPbI3 -(MA = CH3NH3) single-crystal films (SCFs) on MAPbBr3 single crystal substrates in MAPbI3 precursor solution during crystallization process via solution-processed epitaxy. Benefit from the good lattice matching, epitaxial MAPbI3 SCFs with high crystallinity and smooth morphology are of comparable quality to MAPbI3 PSCs and are of better quality than MAPbI3 polycrystalline films. Here we report that epitaxial MAPbI3 SCFs have a low trap density of 5.64×1011 cm–3 and a long carrier lifetime of 11.86 μs. In this work, photodetector based on epitaxial MAPbI3 single-crystal film (SCF) exhibits an excellent stability of a long-term stable response after 120 days, a fast response time of 2.21 μs, a high responsivity of 1.2 A W–1 and a high detectivity of 3.07 ×1012 jones.
研究领域:
材料科学
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光电技术
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半导体物理
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry C
·
2025
·
IF 5.1
Dong Liu,Yuxin Li,Dalin Li,Bin Lu,Zheng Guo,Qian Chen,Xiaojing Zhang,Yaxue Wang,Tao He
Although crystallographic engineering of perovskite single crystals offers a promising route to optimize optoelectronic performance, the intrinsic charge transport mechanisms governing facet-dependent anisotropy remain poorly understood. Herein, we resolve this issue through comparative analysis of stoichiometry-controlled MAPbI3 single crystals with dominant (100) and (001) facets. The PbI2-terminated (001) facet achieves enhanced atmospheric stability via oxygen-mediated passivation and reduced hydration susceptibility, contrasting sharply with the air-sensitized MAI-dominated (100) surface. Bulk characterization further identifies 18% higher mechanical hardness and 15% lower trap density in (001)-oriented crystals compared to (100) counterparts. Synergistically, the (001) facet exhibits an 18% elevated ion migration activation energy (0.59 eV) and superior Hall effect mobility (7.3 cm2V-1s-1 at 180 K), surpassing (100) by 1.55 ×. Temperature-dependent field-effect transistors corroborate this anisotropy, yielding a peak mobility of 14.7 cm2V-1s-1 for (001) versus 8.3 cm2V-1s-1 for (100). Our findings establish crystallographic orientation as a pivotal design parameter, with PbI2-terminated (001) facets offering atomic-scale insights for advancing high-efficiency perovskite optoelectronics.
研究领域:
材料科学
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凝聚态物理
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半导体物理
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晶体工程
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光电子学
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2022
·Vol. 14
·期 16
·6109-6117
·
IF 8.307
Junyu Li,Yousheng Zou,Dawei Hu,Yu Gu,Zeyao Han,Jiaxin Liu,Xiaobao Xu
Terahertz (THz) detection technology is getting increasing attention from scientists and industries alike due to its superiority in imaging, communication, and defense. Unfortunately, the detection of THz electromagnetic waves under room temperature requires a complicated device architecture design or additional cryogenic cooling units, which increase the cost and complexity of devices, subsequently imposing an impediment in its universal application. In this work, THz detectors operated under room temperature are designed based on the thermoelectric effect with MAPbI3 single crystals (SCs) as active layers. With solution-processed molecular growth engineering, the anti-reflection 2D perovskite layers were constructed on SCs’ surfaces to suppress THz reflection loss. Simultaneously, by finely regulating the main carrier types and the direction of the applied bias across the inclined energy level, the thermoelectric effect is further promoted. As a result, THz-induced ΔT in MAPbI3 SCs reaches 4.6 °C, while the enhancement in the bolometric and photothermoelectric effects reach ∼4.8 times and ∼16.9 times, respectively. Finally, the devices achieve responsivity of 88.8 μA W−1 at 0.1 THz under 60 V cm−1, noise equivalent power (NEP) less than 2.16 × 10−9 W Hz−1/2, and specific detectivity (D*) of 1.5 × 108 Jones, which even surpasses the performance of state-of-the-art graphene-based room-temperature THz thermoelectric devices. More importantly, proof-of-concept imaging gives direct evidence of perovskite-based THz sensing in practical applications.
研究领域:
材料科学
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电磁波检测
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纳米技术
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半导体物理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）