共查询到20条相似文献,搜索用时 31 毫秒
1.
Yameng Chen Zhaoyu Wang Dr. Youchao Wei Prof. Yongsheng Liu Prof. Maochun Hong 《Angewandte Chemie (International ed. in English)》2023,62(18):e202301684
Exciton localization is an approach for preparing highly luminescent semiconductors. However, realizing strongly localized excitonic recombination in low-dimensional materials such as two-dimensional (2D) perovskites remains challenging. Herein, we first propose a simple and efficient Sn2+ vacancy (VSn) tuning strategy to enhance excitonic localization in 2D (OA)2SnI4 (OA=octylammonium) perovskite nanosheets (PNSs), increasing their photoluminescence quantum yield (PLQY) to ≈64 %, which is among the highest values reported for tin iodide perovskites. Combining experimental with first-principles calculation results, we confirm that the significantly increased PLQY of (OA)2SnI4 PNSs is primarily due to self-trapped excitons with highly localized energy states induced by VSn. Moreover, this universal strategy can be applied for improving other 2D Sn-based perovskites, thereby paving a new way to fabricate diverse 2D lead-free perovskites with desirable PL properties. 相似文献
2.
Hebin Wang Junzi Li Haolin Lu Sehrish Gull Tianyin Shao Yunxin Zhang Tengfei He Prof. Yongsheng Chen Prof. Tingchao He Prof. Guankui Long 《Angewandte Chemie (International ed. in English)》2023,62(41):e202309600
Due to the pronounced anisotropic response to circularly polarized light, chiral hybrid organic–inorganic metal halides have been regarded as promising candidates for the application in nonlinear chiroptics, especially for the second-harmonic generation circular dichroism (SHG-CD) effect. However, designing novel lead-free chiral hybrid metal halides with large anisotropy factors and high laser-induced damage thresholds (LDT) of SHG-CD remains challenging. Herein, we develop the first chiral hybrid germanium halide, (R/S-NEA)3Ge2I7⋅H2O (R/S-NGI), and systematically investigated its linear and nonlinear chiroptical properties. S-NGI and R-NGI exhibit large anisotropy factors (gSHG-CD) of 0.45 and 0.48, respectively, along with a high LDT of 38.46 GW/cm2; these anisotropy factors were the highest values among the reported lead-free chiral hybrid metal halides. Moreover, the effective second-order nonlinear optical coefficient of S-NGI could reach up to 0.86 pm/V, which was 2.9 times higher than that of commercial Y-cut quartz. Our findings facilitate a new avenue toward lead-free chiral hybrid metal halides, and their implementation in nonlinear chiroptical applications. 相似文献
3.
Iwan Zimmermann Sadig Aghazada Mohammad Khaja Nazeeruddin 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(4):1084-1088
Organic‐inorganic hybrid perovskites have attracted great attention over the last few years as potential light‐harvesting materials for efficient and cost‐effective solar cells. However, the use of lead iodide in state‐of‐the‐art perovskite devices may demonstrate an obstacle for future commercialization due to toxicity of lead. Herein we report on the synthesis and characterization of low dimensional tin‐based perovskites. We found that the use of symmetrical imidazolium‐based cations such as benzimidazolium (Bn) and benzodiimidazolium (Bdi) allow the formation of 2D perovskites with relatively narrow band gaps compared to traditional ‐NH3+ amino groups, with optical band gap values of 1.81 eV and 1.79 eV for Bn2SnI4 and BdiSnI4 respectively. Furthermore, we demonstrate that the optical properties in this class of perovskites can be tuned by formation of a quasi 2D perovskite with the formula Bn2FASn2I7. Additionally, we investigate the change in band gap in the mixed Sn/Pb solid solution Bn2SnxPbx?1I4. Devices fabricated with Bn2SnI4 show promising efficiencies of around 2.3 %. 相似文献
4.
Fuxiang Ji Johan Klarbring Dr. Feng Wang Dr. Weihua Ning Dr. Linqin Wang Dr. Chunyang Yin Dr. José Silvestre Mendoza Figueroa Dr. Christian Kolle Christensen Dr. Martin Etter Prof. Thomas Ederth Prof. Licheng Sun Prof. Sergei I. Simak Prof. Igor A. Abrikosov Prof. Feng Gao 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(35):15303-15306
Environmentally friendly halide double perovskites with improved stability are regarded as a promising alternative to lead halide perovskites. The benchmark double perovskite, Cs2AgBiBr6, shows attractive optical and electronic features, making it promising for high-efficiency optoelectronic devices. However, the large band gap limits its further applications, especially for photovoltaics. Herein, we develop a novel crystal-engineering strategy to significantly decrease the band gap by approximately 0.26 eV, reaching the smallest reported band gap of 1.72 eV for Cs2AgBiBr6 under ambient conditions. The band-gap narrowing is confirmed by both absorption and photoluminescence measurements. Our first-principles calculations indicate that enhanced Ag–Bi disorder has a large impact on the band structure and decreases the band gap, providing a possible explanation of the observed band-gap narrowing effect. This work provides new insights for achieving lead-free double perovskites with suitable band gaps for optoelectronic applications. 相似文献
5.
Tao Song Cheng-Qiang Wang Haolin Lu Dr. Xi-Jiao Mu Bo-Long Wang Ji-Zhong Liu Dr. Bo Ma Prof. Jing Cao Prof. Chuan-Xiang Sheng Prof. Guankui Long Prof. Qiang Wang Prof. Hao-Li Zhang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2024,136(21):e202400769
Generating circularly polarized luminescence (CPL) with simultaneous high photoluminescence quantum yield (PLQY) and dissymmetry factor (glum) is difficult due to usually unmatched electric transition dipole moment (μ) and magnetic transition dipole moment (m) of materials. Herein we tackle this issue by playing a “cascade cationic insertion” trick to achieve strong CPL (with PLQY of ~100 %) in lead-free metal halides with high glum values reaching −2.3×10−2 without using any chiral inducers. Achiral solvents of hydrochloric acid (HCl) and N, N-dimethylformamide (DMF) infiltrate the crystal lattice via asymmetric hydrogen bonding, distorting the perovskite structure to induce the “intrinsic” chirality. Surprisingly, additional insertion of Cs+ cation to substitute partial (CH3)2NH2+ transforms the chiral space group to achiral but the crystal maintains chiroptical activity. Further doping of Sb3+ stimulates strong photoluminescence as a result of self-trapped excitons (STEs) formation without disturbing the crystal framework. The chiral perovskites of indium-antimony chlorides embedded on LEDs chips demonstrate promising potential as CPL emitters. Our work presents rare cases of chiroptical activity of highly luminescent perovskites from only achiral building blocks via spontaneous resolution as a result of symmetry breaking. 相似文献
6.
Peigeng Han Cheng Luo Songqiu Yang Yang Yang Prof. Dr. Weiqiao Deng Prof. Dr. Keli Han 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(31):12809-12813
Zero-dimensional (0D) lead-free perovskites have unique structures and optoelectronic properties. Undoped and Sb-doped all inorganic, lead-free, 0D perovskite single crystals A2InCl5(H2O) (A=Rb, Cs) are presented that exhibit greatly enhanced yellow emission. To study the effect of coordination H2O, Sb-doped A3InCl6 (A=Rb, Cs) are also synthesized and further studied. The photoluminescence (PL) color changes from yellow to green emission. Interestingly, the photoluminescence quantum yield (PLQY) realizes a great boost from <2 % to 85–95 % through doping Sb3+. We further explore the effect of Sb3+ dopants and the origin of bright emission by ultrafast transient absorption techniques. Furthermore, Sb-doped 0D rubidium indium chloride perovskites show excellent stability. These findings not only provide a way to design a set of new high-performance 0D lead-free perovskites, but also reveal the relationship between structure and PL properties. 相似文献
7.
Lin Sui Li Dr. Wen Juan Wei Hong Qiang Gao Yu Hui Tan Dr. Xiao Bo Han 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(35):9054-9059
Two-dimensional hybrid halide perovskites with single chiral and ferroelectricity together with various structural phase transitions provide the possibility for more diverse functional properties. Here, we present a 2D chiral hybrid halide perovskite ferroelectric, [C6H5(CH2)4NH3]2CdCl4 (4PBA−CdCl4, 4PBA=4-phenylbutylamine) that experiences two continuous phase transitions from centrosymmetric triclinic P to polar chiral monoclinic P2 and then to another centrosymmetric tetragonal P4/mmm with increasing temperature, accompanied by symmetry breaking, due to the prominent octahedral distortion and disorder transformation of organic 4PBA cations. In the polar chiral phase, 4PBA−CdCl4 gives a significant CD signal and has a moderate ferroelectric polarization of 0.35 μC/cm2. In addition, 4PBA−CdCl4 occupies a wide band gap of 4.376 eV that is chiefly contributed by the inorganic CdCl6 octahedron. This finding offers an alternative pathway for designing new phase transitions and related physical properties in hybrid halide perovskites and other hybrid crystals. 相似文献
8.
Fei-Fei Gao Haipeng Song Zhi-Gang Li Dr. Yan Qin Xiang Li Dr. Zhao-Quan Yao Jia-Hui Fan Prof. Dr. Xiang Wu Prof. Dr. Wei Li Prof. Dr. Xian-He Bu 《Angewandte Chemie (International ed. in English)》2023,62(12):e202218675
The chemical diversity and structural flexibility of lead halide perovskites (LHPs) offer tremendous opportunities to tune their optical properties through internal molecular engineering and external stimuli. Herein, we report the wide-range and ultrapure photoluminescence emissions in a family of homologous 2D LHPs, [MeOPEA]2PbBr4−4xI4x (MeOPEA=4-methoxyphenethylammonium; x=0, 0.2, 0.425, 0.575, 1) enabled through internal chemical pressure and external hydrostatic pressure. The chemical pressure, induced by the C−H⋅⋅⋅π interactions and halogen doping/substitution strengthens the structural rigidity to give sustained narrow emissions, and regulates the emission energy, respectively. Further manipulation of physical pressure leads to wide-range emission tuning from 412 to 647 nm in a continuous and reversible manner. This work could open up new pathways for developing 2D LHP emitters with ultra-wide color gamut and high color purity which are highly useful for pressure sensing. 相似文献
9.
Achieving Color-Tunable Long Persistent Luminescence in Cs2CdCl4 Ruddlesden-Popper Phase Perovskites
Ya Liu Shuangpeng Yan Tianchi Wang Qingshan He Xiaodie Zhu Chao Wang Daiyuan Liu Dr. Ting Wang Prof. Dr. Xuhui Xu Prof. Dr. Xue Yu 《Angewandte Chemie (International ed. in English)》2023,62(37):e202308420
Two-dimensional (2D)-halide perovskites have been enriched over recent years to offer remarkable features from diverse chemical structures and environmental stability endowed with exciting functionalities in photoelectric detectors and phosphorescence systems. However, the low conversion efficiency of singlet to triplet in 2D hybrid halide perovskites reduces phosphorescence lifetimes. In this study, the long persistent luminescence of 2D all-inorganic perovskites with a self-assembled 2D interlayer galleries structure is investigated. The results show that the decay time of the long persistent luminescence increases from 450 s to 600 s, and the luminescence color changes from cyan to orange, and the thermal stability of photoluminescence enhances dramatically after replacing Cd2+ by appropriate Mn2+ ions in 2D Cs2CdCl4 Ruddlesden-Popper phase perovskites. Furthermore, diversified anti-counterfeiting modes are fabricated to highlight the promising applications of Cs2CdCl4 perovskite systems with tunable persistent luminescence in advanced anti-counterfeiting. Therefore, our studies provide a novel model for realizing tunable long persistent luminescence of perovskite with 2D self-assembled layered structure for advanced anti-counterfeiting. 相似文献
10.
Minghao Li Shahana Nizar Sudipta Saha Anoop Thomas Stefano Azzini Thomas W. Ebbesen Cyriaque Genet 《Angewandte Chemie (International ed. in English)》2023,62(6):e202212724
We show that chiral Frenkel excitons yield intense circularly polarized luminescence with an intrinsic dissymmetry factor in emission glum as high as 0.08. This outstanding value is measured through thin films of cyanine J-aggregates that form twisted bundles. Our measurements, obtained by a Mueller polarization analysis, are artifact-free and reveal a quasi-perfect correlation between the dissymmetry factors in absorption, gabs, and in emission glum. We interpret the bisignate dissymmetry factors as the signature of a strong coupling between chiral Frenkel excitons longitudinally excited along the bundles. We further resolve by polarimetry analysis the split in energy between the excited states with a Davydov splitting as small as 28 meV. We finally show the anti-Kasha nature of the chiral emission bands with opposite optical chirality. These mirror-imaged emissive chiroptical features emerge from the structural rigidity of the bundles that preserves the ground- and excited-state chirality. 相似文献
11.
Yuanyuan Fang Long Zhang Lianwei Wu Jiejuan Yan Yu Lin Kai Wang Wendy L. Mao Bo Zou 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(43):15393-15397
Two‐dimensional (2D) halide perovskites have attracted significant attention due to their compositional flexibility and electronic diversity. Understanding the structure–property relationships in 2D double perovskites is essential for their development for optoelectronic applications. In this work, we observed the emergence of pressure‐induced emission (PIE) at 2.5 GPa with a broad emission band and large Stokes shift from initially nonfluorescent (BA)4AgBiBr8 (BA=CH3(CH2)3NH3+). The emission intensity increased significantly upon further compression up to 8.2 GPa. Moreover, the band gap narrowed from the starting 2.61 eV to 2.19 eV at 25.0 GPa accompanied by a color change from light yellow to dark yellow. Analysis of combined in situ high‐pressure photoluminescence, absorption, and angle‐dispersive X‐ray diffraction data indicates that the observed PIE can be attributed to the emission from self‐trapped excitons. This coincides with [AgBr6]5? and [BiBr6]3? inter‐octahedral tilting which cause a structural phase transition. High‐pressure study on (BA)4AgBiBr8 sheds light on the relationship between the structure and optical properties that may improve the material's potential applications in the fields of pressure sensing, information storage and trademark security. 相似文献
12.
《中国化学快报》2023,34(8):107980
Chiral organic-inorganic metal halide semiconductors (OIMHSs) have recently attracted numerous interests due to their unique chirality, structural tunability, and extensive physical properties. However, most reported chiral OIMHSs contain toxic lead, which will be a potential obstacle to their further applications. Herein, we successfully synthesized a novel chiral lead-free tin(IV)-based OIMHS [(R)-3-hydroxyquinuclidinium]2SnCl6 ([R-HQ]2SnCl6). It exhibits a wide band gap (Eg) of about 4.11 eV. Moreover, [R-HQ]2SnCl6 undergoes a phase transition around 330 K (Tc) and shows distinct dielectric switching characteristics with good repeatability. This work enriches the chiral lead-free OIMHS family and stimulates further exploration of chiral lead-free OIMHS switching materials 相似文献
13.
Qianwen Guan Tingting Zhu Zeng-Kui Zhu Huang Ye Shihai You Peng Xu Jianbo Wu Xinyi Niu Chengshu Zhang Prof. Xitao Liu Prof. Junhua Luo 《Angewandte Chemie (International ed. in English)》2023,62(32):e202307034
Chiral three-dimensional hybrid organic–inorganic perovskites (3D HOIPs) would show unique chiroptoelectronic performance due to the combination of chirality and 3D structure. However, the synthesis of 3D chiral HOIPs remains a significant challenge. Herein, we constructed a pair of unprecedented 3D chiral halide perovskitoids (R/S-BPEA)EA6Pb4Cl15 ( 1-R/S ) (R/S-BPEA=(R/S)-1-4-Bromophenylethylammonium, EA=ethylammonium), in which the large chiral cations can be contained in the big “hollow” inorganic frameworks induced by mixing cations. Notably, 3D 1-R/S shows natural chiroptical activity, as evidenced by its significant mirror circular dichroism spectra and the ability to distinguish circularly polarized light. Moreover, based on the unique 3D structure, 1-S presents sensitive X-ray detection performance with a low detection limit of 398 nGyair s−1, which is 14 times lower than the regular medical diagnosis of 5.5 μGyair s−1. In this work, 3D chiral halide perovskitoids provide a new route to develop chiral material in spintronics and optoelectronics. 相似文献
14.
Fuxiang Ji Johan Klarbring Feng Wang Weihua Ning Linqin Wang Chunyang Yin Jos Silvestre Mendoza Figueroa Christian Kolle Christensen Martin Etter Thomas Ederth Licheng Sun Sergei I. Simak Igor A. Abrikosov Feng Gao 《Angewandte Chemie (International ed. in English)》2020,59(35):15191-15194
Environmentally friendly halide double perovskites with improved stability are regarded as a promising alternative to lead halide perovskites. The benchmark double perovskite, Cs2AgBiBr6, shows attractive optical and electronic features, making it promising for high‐efficiency optoelectronic devices. However, the large band gap limits its further applications, especially for photovoltaics. Herein, we develop a novel crystal‐engineering strategy to significantly decrease the band gap by approximately 0.26 eV, reaching the smallest reported band gap of 1.72 eV for Cs2AgBiBr6 under ambient conditions. The band‐gap narrowing is confirmed by both absorption and photoluminescence measurements. Our first‐principles calculations indicate that enhanced Ag–Bi disorder has a large impact on the band structure and decreases the band gap, providing a possible explanation of the observed band‐gap narrowing effect. This work provides new insights for achieving lead‐free double perovskites with suitable band gaps for optoelectronic applications. 相似文献
15.
Tin halide perovskites are potential alternatives of lead halide perovskites. However, the easy oxidation of Sn2+ to Sn4+ brings in a challenge. Recently, layered two-dimensional hybrid tin halide perovskites have been shown to partially resist the oxidation process because of the presence of hydrophobic organic molecules. Consequently, such layered hybrid perovskites are being explored for optoelectronic applications. The optical properties of layered tin halide perovskites depend on the interlayer separation and the dielectric mismatch between the organic and inorganic layers. Intercalation (insertion) of a molecular species between the layers modifies the interlayer interactions affecting the optical properties of layered hybrid perovskites. We investigated the effect of hexafluorobenzene (HFB) intercalation in phenethylammonium tin iodide [(PEA)2SnI4] using temperature-dependent (6 K to 300 K) photoluminescence (PL). HFB intercalation increases the bandgap. A strong PL quenching is observed in pristine (PEA)2SnI4 below 150 K, probably because of the presence of non-emissive states. HFB intercalation suppresses the influence of such non-emissive states resulting in an increase in PL intensity at the cryogenic temperatures. Our results highlight that a simple molecular intercalation (non-covalent interaction) into layered hybrid perovskites can significantly tailor the electronic and optical properties. 相似文献
16.
Zonghan Hong Wee Kiang Chong Andrew Yun Ru Ng Mingjie Li Rakesh Ganguly Tze Chien Sum Han Sen Soo 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(11):3494-3498
Two‐dimensional lead and tin halide perovskites were prepared by intercalating the long alkyl group 1‐hexadecylammonium (HDA) between the inorganic layers. We observed visible‐light absorption, narrow‐band photoluminescence, and nanosecond photoexcited lifetimes in these perovskites. Owing to their hydrophobicity and stability even in humid air, we applied these perovskites in the decarboxylation and dehydrogenation of indoline‐2‐carboxylic acids. (HDA)2PbI4 or (HDA)2SnI4 were investigated as photoredox catalysts for these reactions, and quantitative conversion and high yields were observed with the former. 相似文献
17.
Chang-Yuan Su Ye-Feng Yao Zhi-Xu Zhang Ying Wang Ming Chen Pei-Zhi Huang Yi Zhang Wen-Cheng Qiao Da-Wei Fu 《Chemical science》2022,13(17):4794
Two-dimensional (2D) hybrid double perovskites have attracted extensive research interest for their fascinating physical properties, such as ferroelectricity, X-ray detection, light response and so on. In addition, ferroelastics, as an important branch of ferroic materials, exhibits wide prospects in mechanical switches, shape memory and templating electronic nanostructures. Here, we designed a 2D phase-transition double perovskite ferroelastic through a structurally progressive strategy. This evolution is core to our construction process from 0D to 1D and AgBi-based 2D. In this way, we successfully synthesized 2D lead-free ferroelastic (DPA)4AgBiBr8 (DPA = 2,2-dimethylpropan-1-aminium) with a high Curie temperature (Tc), which shows a narrower band gap than 0D (DPA)4Bi2Br10 and 1D (DPA)5Pb2Br9. Moreover, the mechanism of structural phase transition and molecular motion are fully characterized by temperature dependent solid-state NMR and single crystal XRD. (DPA)4AgBiBr8 injects power into the discovery of new ferroelastics or the construction and dimensional adjustment in new hybrid double perovskites.By using a lead-free AgBi-based scheme, we successfully synthesized a two-dimensional double perovskite ferroelastic (DPA)4AgBiBr8 with high Tc of 375 K and a narrow band gap of 2.44 eV, where DPA is 2,2-dimethylpropan-1-aminium. 相似文献
18.
Dr. Sachin Thawarkar Dr. Sachin R. Rondiya Dr. Nelson Y. Dzade Dr. Nageshwar Khupse Dr. Sandesh Jadkar 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(26):7408-7417
Lead-free double perovskites have emerged as stable and non-toxic alternatives to Pb-halide perovskites. Herein, the synthesis of Fe-doped Cs2AgBiCl6 lead-free double perovskites are reported that display blue emission using an antisolvent method. The crystal structure, morphology, optical properties, band structure, and stability of the Fe-doped double perovskites were investigated systematically. Formation of the Fe-doped Cs2AgBiCl6 double perovskite is confirmed by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analysis. XRD and thermo-gravimetric analysis (TGA) shows that the Cs2AgBiCl6 double perovskite has high structural and thermal stability, respectively. Field emission scanning electron microscopy (FE-SEM) analysis revealed the formation of dipyramidal shape Cs2AgBiCl6 crystals. Furthermore, energy-dispersive X-ray spectroscopy (EDS) mapping shows the overlapping of Cs, Bi, Ag, Fe, and Cl elements and homogenous incorporation of Fe in Cs2AgBiCl6 double perovskite. The Fe-doped Cs2AgBiCl6 double perovskite shows a strong absorption at 380 nm. It extends up to 700 nm, suggesting that sub-band gap states transition may originate from the surface defect of the doped perovskite material. The radiative kinetics of the crystals was studied using the time-correlated single-photon counting (TCSPC) technique. Lattice parameters and band gap value of the Fe-doped Cs2AgBiCl6 double perovskites predicted by the density functional theory (DFT) calculations are confirmed by XRD and UV/Visible spectroscopy analysis. Time-dependent photo-response characteristics of the Fe-doped Cs2AgBiCl6 double perovskite show fast response and recovery time of charge carriers. We believe that the successful incorporation of Fe in lead-free, environmentally friendly Cs2AgBiCl6 double perovskite can open a new class of doped double perovskites with significant potential optoelectronics devices fabrication and photocatalytic applications. 相似文献
19.
Yangyang Dang Yian Zhou Xiaolong Liu Dianxing Ju Prof. Dr. Shengqing Xia Prof. Dr. Haibing Xia Prof. Dr. Xutang Tao 《Angewandte Chemie (International ed. in English)》2016,55(10):3447-3450
Hybrid perovskites have generated a great deal of interest because of their potential in photovoltaic applications. However, the toxicity of lead means that there is interest in finding a nontoxic substitute. Bulk single crystals of both cubic CH3NH3SnI3 and CH(NH2)2SnI3 were obtained by using the top‐seeded solution growth method under an ambient atmosphere. Structural refinement, band gap, thermal properties, and XPS measurements of CH3NH3SnI3 and CH(NH2)2SnI3 single crystals are also reported in detail. These results should pave the way for further applications of CH3NH3SnI3 and CH(NH2)2SnI3. 相似文献
20.
Yuyin Wang Xitao Liu Lina Li Chengmin Ji Zhihua Sun Shiguo Han Kewen Tao Junhua Luo 《化学:亚洲杂志》2019,14(9):1530-1534
Inorganic–organic hybrid perovskites, especially two‐dimensional (2D) layered halide perovskites, have attracted significant attention due to their unique structures and attractive optoelectronic properties, which open up a great opportunity for next‐generation photosensitive devices. Herein, we report a new 2D bilayered inorganic–organic hybrid perovskite, (C6H13NH3)2(NH2CHNH2)Pb2I7 ( HFA , where C6H13NH3+ is hexylaminium and NH2CHNH2+ is formamidinium), which exhibits a remarkable photoresponse under broadband light illumination. Structural characterizations demonstrate that the 2D perovskite structure of HFA is constructed by alternant stacking of inorganic lead iodide bilayered sheets and organic hexylaminium layers. Optical absorbance measurements combined with density functional theory (DFT) calculations suggest that HFA is a direct band gap semiconductor with a narrow band gap (Eg) of ≈2.02 eV. Based on these findings, photodetectors based on HFA crystal wafer are fabricated, which exhibit fascinating optoelectronic properties including large on/off current ratios (over 103), fast response speeds (τrise=310 μs and τdecay=520 μs) and high responsivity (≈0.95 mA W?1). This work will contribute to the design and development of new two‐dimensional bilayer inorganic–organic hybrid perovskites for high‐performance photosensitive devices. 相似文献