共查询到20条相似文献,搜索用时 15 毫秒
1.
Miao He Zhuhua Xu Cong Zhao Yu Gao Kanghui Ke Na Liu Xiongxian Yao Feiyu Kang Yang Shen Liwei Lin Guodan Wei 《Advanced functional materials》2023,33(24):2300282
Sn-based perovskite materials are promising lead-free alternatives in thin film photodetectors (PDs) for applications such as optical communications, night visions and biomedical near-infrared imaging systems. However, constructing Sn-based photodetectors with high sensitivity, ultrafast response, and good operation stability has been a challenge. Herein, the phenyl-ethyl ammonium (PEA+) additive is introduced in pristine FASnI3, which regulates the thin film growth, passivates the trap/defect states, prevents Sn2+/Sn4+oxidation, and releases the crystal strain. The Resulting FA0.8PEA0.2SnI3 thin films exhibit highly crystalline order and flexibility. A self-powered PD using FA0.8PEA0.2SnI3 as the active layer demonstrates excellent responsivity of 0.262 W−1, detectivity of 2.3 × 1011 Jones. And it possesses the fastest rise and decay time of 25 µs and 42 µs as compared with the state-of-art Sn-based perovskite PDs. The transient absorption spectroscopy analysis validates greatly reduced trapping states and defects of FASnI3 with the PEA+ film for ultrafast response. A flexible Sn-based perovskite PD without any encapsulation in air continuously shows ultrafast responses after 10,000 bending cycles. Meanwhile, a flexible imaging system can be realized by a 5 × 5 PD array with good sensing results. This study shows great potential in nontoxic and ultrafast Sn-based perovskite PDs for flexible imaging applications. 相似文献
2.
Yuan-Wen Hsiao Bi Shane Cheng Hung-Chieh Hsu Shih-Hsiung Wu Hsuan-Ta Wu Ching-Chich Leu Chuan-Feng Shih 《Advanced functional materials》2023,33(21):2300169
This research demonstrates a state-of-the-art vertical-transport photodetector with an n-type 3D MAPbI3/p-type quasi-2D (Q-2D) BA2MA2Pb3I10 perovskite heterojunction. This structure introduces a ≈0.6 V built-in electric field at the n-p junction that greatly improves the characteristics of the perovskite photodetector, and the presence of Q-2D perovskite on the surface improves the life. The electrical polarities of the 3D and the Q-2D perovskite layers are simply controlled by self-constituent doping, making clearly defined n-p characteristics. Doctor-blade coating is used to fabricate the photodetector with a large area. The Q-2D materials with highly oriented (040) Q-2D (n = 2,3) planes are near the surface, and the (111) preferred planes mixed with high index Q-2D materials (n = 4,5) are found near the 3D/Q-2D interface. The stacking and interface are beneficial for carrier extraction and transport, yielding an external quantum efficiency of 77.9%, a carrier lifetime long as 295.7 ns, and a responsibility of 0.41 A W−1. A low dark current density of 6.2 × 10−7 mA cm−2 and a high detectivity of 2.82 × 1013 Jones are obtained. Rise time and fall time are fast as 1.33 and 10.1 µs, respectively. The results show the application potential of 3D/Q-2D n-p junction perovskite photodetectors. 相似文献
3.
2D Hybrid Perovskite Ferroelectric Enables Highly Sensitive X‐Ray Detection with Low Driving Voltage
Chengmin Ji Sasa Wang Yaxing Wang Huaixi Chen Lina Li Zhihua Sun Yan Sui Shuao Wang Junhua Luo 《Advanced functional materials》2020,30(5)
X‐ray detectors with high sensitivity are of great significance in both civil and military fields. Over the past decades, great efforts have been made to improve the sensitivity in conventional inorganic materials, but mainly at the cost of increasing the energy consumption with a quite high operating voltage. Developing photosensitive ferroelectrics directly as detector materials may be a conceptually new strategy in view of the strong ferroelectric spontaneous polarization (Ps) that assists photoinduced carriers separation and transport. A high‐performance X‐ray detector in 2D hybrid halide perovskite ferroelectric (C4H9NH3)2(C2H5NH3)2Pb3Br10 ( BA2EA2Pb3Br10 ) (Ps = 5 µC cm?2) is fabricated and exhibits an ultrahigh X‐ray sensitivity up to 6.8 × 103 µC Gyair?1 cm?2 even at a relatively low operating voltage, which is over 300‐fold larger than that of state‐of‐the‐art α‐Se X‐ray detectors. Such a brilliant figure‐of‐merit is largely attributed to the superior mobility–lifetime products associated with the strong ferroelectric polarization of BA2EA2Pb3Br10 . As pioneering work, these findings inform the exploration of hybrid halide perovskite ferroelectrics toward high‐performance photoelectronic devices. 相似文献
4.
Organic-inorganic hybrid perovskite solar cells (PSCs) with unique properties exhibit their powerful competitiveness in the photovoltaic field over the past few years. However, the challenges of stability for perovskite devices limit the commercialization and further development. The 2D/3D hybrid structures combine the superior efficiency of bulk perovskites and the superior stability of layered perovskites and gradually get hotspots of the photovoltaic field. In addition, there remains a lack of comprehensive understanding and systematic summary of the function of 2D perovskite attributed to the complex nature of 2D/3D structures. Here, the latest progress of 2D/3D hybrid structures and focus on the functionality of 2D phases in mixed structures and the underlying mechanism from the perspective of their different distributions in the perovskite layer is summarized. Then, the insight and vital factors for overall improvements in the stability of 2D/3D structures are thoroughly discussed. Finally, it is expected that this review will contribute to the present challenges and future research prospects in the photovoltaic industry. 相似文献
5.
Gaosong Chen Yuchen Qiu Hanfei Gao Yingjie Zhao Jiangang Feng Lei Jiang Yuchen Wu 《Advanced functional materials》2020,30(14)
State‐of‐the‐art optoelectronic devices based on metal‐halide perovskites demand solution‐processed structures with high crystallinity, controlled crystallographic orientation, and enhanced environmental stability. Formamidinium lead iodide (α‐FAPbI3) possesses a suitable bandgap of 1.48 eV and enhanced thermal stability, whereas perovskite‐type polymorph (α‐phase) is thermodynamically instable at ambient temperatures. Stable α‐FAPbI3 perovskite 1D structure arrays with high crystallinity and ordered crystallographic orientation are developed by controlled nucleation and growth in capillary bridges. By surface functionalization with phenylethylammonium ions (PEA+), FAPbI3 wires sustain a stable α‐phase after 28 day storage in the ambient environment with a relative humidity of 50%. Enhanced photoluminescence (PL) intensity and elongated PL lifetime demonstrate suppressed trap density and high crystallinity in these 1D structures, which is also reflected by the enhanced diffraction density and pure (001) crystallographic orientation in the grazing‐incidence wide‐angle X‐ray scattering (GIWAXS) pattern. Based on these high‐quality 1D structures, sensitive photodetectors are achieved with average responsivities of 5282 A W?1, average specific detectivities of more than 1.45 × 1014 Jones, and a fast response speed with a 3 dB bandwidth of 15 kHz. 相似文献
6.
Dezhong Zhang Yunxing Fu Chunyu Liu Chenyang Zhao Xiang Gao Jidong Zhang Wenbin Guo Jun Liu Chuanjiang Qin Lixiang Wang 《Advanced functional materials》2021,31(38):2103890
Quasi-2D perovskites with enlarged exciton binding energy and tunable bandgap are appealing for application in perovskite light-emitting diodes (PeLEDs). However, wide n domains distribution is commonly formed in solution-processed quasi-2D perovskite films due to the uncontrollable crystallization behavior, which leads to low device performance. Here, the crystallization process is successfully regulated to narrow the n domains distribution by introducing compound additive of ZrO2 nanoparticles (NPs) and Cryptand complexant. ZrO2 NPs can avoid the segregation of organic large and small cations by strengthening the solvent extraction capacity of antisolvent, while Cryptand offsets the poor solubility of PbBr2 by forming an intermediate state to slow down the crystallization of high-n domains. Consequently, both high photoluminescence quantum yields over 90% and a high external quantum efficiency of 21.2% are obtained in the optimized green quasi-2D PeLEDs. Moreover, the lifetime extends about four times compared with control devices. The strategy of domain controlling by compound additive provides a powerful way to develop high-performance quasi-2D perovskite optoelectrical devices. 相似文献
7.
Mingfa Peng Yulong Ma Lei Zhang Shan Cong Xuekun Hong Yiheng Gu Yawei Kuang Yushen Liu Zhen Wen Xuhui Sun 《Advanced functional materials》2021,31(42):2105051
Perovskites have attracted intensive attention as promising materials for the application in various optoelectronic devices due to their large light absorption coefficient, high carrier mobility, and long charge carrier diffusion length. However, the performance of the pure perovskite nanocrystals-based device is extremely restricted by the limited charge transport capability due to the existence of a large number of the grain boundary between perovskite nanocrystals. To address these issues, a high-performance photodetector based on all-inorganic CsPbBr3 perovskite nanocrystals/2D non-layered cadmium sulfide selenide heterostructure has been demonstrated through energy band engineering with designed typed-II heterostructure. The photodetector exhibits an ultra-high light-to-dark current ratio of 1.36 × 105, a high responsivity of 2.89 × 102 A W−1, a large detectivity of 1.28 × 1014 Jones, and the response/recovery time of 0.53s/0.62 s. The enhancement of the optoelectronic performance of the heterostructure photodetector is mainly attributed to the efficient charge carrier transfer ability between the all-inorganic CsPbBr3 perovskites and 2D cadmium sulfide selenide resulting from energy band alignment engineering. The charge carriers’ transfer dynamics and the mechanism of the CsPbBr3 perovskites/2D non-layered nanosheets interfaces have also been studied by state-state PL spectra, fluorescence lifetime imaging microscopy, time-resolved photoluminescence spectroscopy, and Kelvin probe force microscopy measurements. 相似文献
8.
Saba Gharibzadeh Ihteaz M. Hossain Paul Fassl Bahram Abdollahi Nejand Tobias Abzieher Moritz Schultes Erik Ahlswede Philip Jackson Michael Powalla Sren Schfer Michael Riencker Tobias Wietler Robby Peibst Uli Lemmer Bryce S. Richards Ulrich W. Paetzold 《Advanced functional materials》2020,30(19)
Wide‐bandgap perovskite solar cells (PSCs) with optimal bandgap (Eg) and high power conversion efficiency (PCE) are key to high‐performance perovskite‐based tandem photovoltaics. A 2D/3D perovskite heterostructure passivation is employed for double‐cation wide‐bandgap PSCs with engineered bandgap (1.65 eV ≤ Eg ≤ 1.85 eV), which results in improved stabilized PCEs and a strong enhancement in open‐circuit voltages of around 45 mV compared to reference devices for all investigated bandgaps. Making use of this strategy, semitransparent PSCs with engineered bandgap are developed, which show stabilized PCEs of up to 25.7% and 25.0% in four‐terminal perovskite/c‐Si and perovskite/CIGS tandem solar cells, respectively. Moreover, comparable tandem PCEs are observed for a broad range of perovskite bandgaps. For the first time, the robustness of the four‐terminal tandem configuration with respect to variations in the perovskite bandgap for two state‐of‐the‐art bottom solar cells is experimentally validated. 相似文献
9.
Dongguen Shin Fengshuo Zu Edgar R. Nandayapa Lennart Frohloff Emily Albert Emil J. W. List-Kratochvil Norbert Koch 《Advanced functional materials》2023,33(2):2208980
The success of using 2D Ruddlesden-Popper metal halide perovskites (MHPs) in optoelectronic devices has ignited great interest as means for energy level tuning at the interface with 3D MHPs. Inter alia, the application of 2D phenylethylammonium lead quaternary iodide (PEA2PbI4)/3D MHPs interfaces has improved various optoelectronic devices, where a staggered type-II energy level alignment is often assumed. However, a type-II heterojunction seems to contradict the enhanced photoluminescence observed for 2D PEA2PbI4/3D MHP interfaces, which raises fundamental questions about the electronic properties of such junctions. In this study, using direct and inverse photoelectron spectroscopy, it is revealed that a straddling type-I energy level alignment is present at 2D PEA2PbI4/3D methylammonium lead triiodide (MAPbI3) interfaces, thus explaining that the photoluminescence enhancement of the 3D perovskite is induced by energy transfer from the 2D perovskite. These results provide a reliable fundamental understanding of the electronic properties at the investigated 2D/3D MHP interfaces and suggest careful (re)consideration of the electronic properties of other 2D/3D MHP heterostructures. 相似文献
10.
Bolun Li Xi Huang Xiang Wu Qiong Zuo Yunhao Cao Qi Zhu Yaohui Li Yuanhuan Xu Guanhaojie Zheng Dongcheng Chen Xu-Hui Zhu Fei Huang Hongyu Zhen Lintao Hou Jian Qing Wanzhu Cai 《Advanced functional materials》2023,33(28):2300216
Quasi-two-dimensional (Q-2D) perovskites are emerging as one of the most promising materials for photodetectors. However, a significant challenge to Q-2D perovskites for photodetection is their insufficient charge transport ability, which is mainly attributed to their hybrid low-dimensional n-phase structure. This study demonstrates that evenly-distributed 3D-like phases with vertical orientation throughout the film can greatly facilitate charge transport and suppress charge recombination, outperforming the prevalent phase structure with a vertical dimension gradient. Based on such a phase structure, a Q-2D Ruddlesden−Popper perovskite self-powered photodetector achieving a combination of exceptional figures-of-merit is realized, including a responsivity of 0.45 AW−1, a peak specific detectivity of 2.3 × 1013 Jones, a 156 dB linear dynamic range, and a rise/fall time of 2.89 µs/1.93 µs. The desired phase structure is obtained by utilizing a double-hole transport layer (HTL), combining hydrophobic PTAA and hydrophilic PEDOT: PSS. Besides, the dependence of the hybrid low-dimensional phase structure is also identified on the surface energy of the buried HTL substrate. This study gives insight into the correlation between Q-2D perovskites’ phase structure and performance, providing a valuable design guide for Q-2D perovskite-based photodetectors. 相似文献
11.
Highly Sensitive Low‐Bandgap Perovskite Photodetectors with Response from Ultraviolet to the Near‐Infrared Region
下载免费PDF全文
![点击此处可从《Advanced functional materials》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Wenbin Wang Dewei Zhao Fujun Zhang Ludong Li Mingde Du Changlei Wang Yue Yu Qianqian Huang Miao Zhang Lingliang Li Jianli Miao Zheng Lou Guozhen Shen Ying Fang Yanfa Yan 《Advanced functional materials》2017,27(42)
It is a great challenge to obtain broadband response perovskite photodetectors (PPDs) due to the relatively large bandgaps of the most used methylammonium lead halide perovskites. The response range of the reported PPDs is limited in the ultraviolet–visible range. Here, highly sensitive PPDs are successfully fabricated with low bandgap (≈1.25 eV) (FASnI3)0.6(MAPbI3)0.4 perovskite as active layers, exhibiting a broadband response from 300 to 1000 nm. The performance of the PPDs can be optimized by adjusting the thicknesses of the perovskite and C60 layers. The optimized PPDs with 1000 nm thick perovskite layer and 70 nm thick C60 layer exhibit an almost flat external quantum efficiency (EQE) spectrum from 350 to 900 nm with EQE larger than 65% under ?0.2 V bias. Meanwhile, the optimized PPDs also exhibit suppressed dark current of 3.9 nA, high responsivity (R ) of over 0.4 A W?1, high specific detectivity (D* ) of over 1012 Jones in the near‐infrared region under ?0.2 V. Such highly sensitive broadband response PPDs, which can work well as self‐powered conditions, offer great potential applications in multicolor light detection. 相似文献
12.
Zhi Zheng Haiyang Li Liang Hai Ruiqi Ma Rui Liu Chunpeng Zhai Zongdong Sun Fei Wang Ying Ma Qingguo Xie Xiaoding Lou Tianyou Zhai Fan Xia 《Advanced functional materials》2024,34(1):2307093
2D perovskites have attracted wide attention for optoelectronic applications because of their unique layer structure and tunable outstanding optical/electrical properties. In addition, 2D Cs3Bi2Br9 nanoflakes possess large effective atomic number, high resistivity, high density as well as excellent stability, rendering it a promising material for X-ray detection. Nevertheless, it is full of challenges to synthesize 2D Cs3Bi2Br9 nanoflakes by conventional inversion temperature crystallization (ITC) strategy due to the existence of Br- vacancies in the Cs3Bi2Br9 crystal nucleus. Herein, an Ag+ assisted ITC (SAITC) strategy to grow 2D Cs3Bi2Br9 nanoflakes is proposed. The synthesis mechanism revealed by both experiments and theoretical calculations can be mainly ascribed to the passivated Br− vacancies and enhanced structure stability by adding Ag+ which can effectively prevent the oxidation of 2D Cs3Bi2Br9 nanoflakes from growth of hybrid crystals. The synthesized high-crystallinity 2D Cs3Bi2Br9 nanoflakes possess direct bandgap characteristic, and the mobility lifetime can reach 9.8 × 10−4 cm2 V−1. Excitingly, the fabricated device based on 2D Cs3Bi2Br9 nanoflakes demonstrates ultrahigh sensitivity of detecting X-ray (1.9 CGyair−1cm−2) at very low driven voltage (0.5 V) due to the photoconductive gain mechanism. The 2D Cs3Bi2Br9 nanoflakes synthesized by SAITC method have great potential for developing highly sensitive optoelectronic devices. 相似文献
13.
Pesi Mwitumwa Hangoma Insoo Shin Hyun‐Seock Yang Danbi Kim Yun Kyung Jung Bo Ram Lee Joo Hyun Kim Kwang Ho Kim Sung Heum Park 《Advanced functional materials》2020,30(34)
Despite the record power conversion efficiencies, inverted perovskite solar cells (PSCs) are still looking to overcome the challenge of moisture instability. This is mitigated by introducing 2D perovskite at the base of a 3D perovskite via coating of ethylenediamine bications on top of the hole transport layer of p–i–n planar configured devices. The cations induce thin 2D perovskite growth beneath the 3D perovskite to create a 2D/3D hybrid active layer. This 2D layer in turn acts as a template for the growth of relatively large grains compared to that of pure 3D perovskite films. This stems from the merging of grain boundaries. The hydrophobicity of the 2D/3D perovskite film consequently improves, as evidenced by a large contact angle of 93.1°, compared to 68.9° for the 3D perovskite film. Because there are fewer defects sourced from grain boundaries, the air‐processed 2D/3D perovskite devices yield a high power conversion efficiency of 15.02%, compared to 13.10% from 3D perovskite devices. When stored in moderately humid environment of 55% relative humidity, the 2D/3D devices exhibit longer stabilities, with 75% of their power conversion efficiencies maintained after 150 h, compared to a total loss in efficiency for 3D device in the same time frame. 相似文献
14.
In Situ Fabrication of Highly Luminescent Bifunctional Amino Acid Crosslinked 2D/3D NH3C4H9COO(CH3NH3PbBr3)n Perovskite Films
下载免费PDF全文
![点击此处可从《Advanced functional materials》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Taiyang Zhang Liqiang Xie Liang Chen Nanjie Guo Ge Li Zhongqun Tian Bingwei Mao Yixin Zhao 《Advanced functional materials》2017,27(1)
The perovskite quantum dots are usually synthesized by solution chemistry and then fabricated into film for device application with some extra process. Here it is reported for the first time to in situ formation of a crosslinked 2D/3D NH3C4H9COO(CH3NH3) n Pbn Br3n perovskite planar films with controllable quantum confine via bifunctional amino acid crosslinkage, which is comparable to the solution chemistry synthesized CH3NH3PbBr3 quantum dots. These atomic layer controllable perovskite films are facilely fabricated and tuned by addition of bi‐functional 5‐aminovaleric acid (Ava) of NH2C4H9COOH into regular (CH3NH3)PbBr3 (MAPbBr3) perovskite precursor solutions. Both the NH3+ and the COO? groups of the zwitterionic amino acid are proposed to crosslink the atomic layer MAPbBr3 units via Pb? COO bond and ion bond between NH3+ and [PbX6] unit. The characterizations by atomic force microscopy, scanning electron microscopy, Raman, and photoluminescence spectroscopy confirm a successful fabrication of ultrasmooth and stable film with tunable optical properties. The bifunctional crosslinked 2D/3D Ava(MAPbBr3)n perovskite films with controllable quantum confine would serve as distinct and promising materials for optical and optoelectronic applications. 相似文献
15.
Yangyang Cai Siyu Yan Xinran Du Tingting Lin Yue-jian Lin Longzhen Qiu Weizhi Wang 《Advanced functional materials》2023,33(5):2211191
2D perovskite is an organic–inorganic hybrid material with good photoelectric properties, generally prepared by using organic groups as isolation molecules. In this study, using manganese chloride and potassium halide as raw materials, all-inorganic 2D lead-free perovskites are prepared by the Bridgeman melting and cooling method. Different from the 2D perovskites synthesized by organic spacer molecules, the prepared all-inorganic 2D perovskites have smaller layer spacings and good crystallization performance due to the use of potassium halide as spacer molecules. They are direct bandgap semiconductors and their energy bandgaps are tuned by the different types of potassium halides. High degree orientation crystal thin films with (001) lattice plane parallel to silicon wafer substrate are prepared by double-source evaporation. The physical morphology of the films is characterized by grazing angle X-ray diffraction, transmission electron microscopy, and electron diffraction. The field effect transistors prepared from these 2D films show excellent electronic characteristics. The mobility of the optimized device is ≈24 cm2 v−1 s−1 and the on/off ratio reaches 105. This study reveals the potential of lead-free manganese 2D perovskite as a high-performance perovskite field effect transistor. 相似文献
16.
Ultra-Stable and Sensitive Ultraviolet Photodetectors Based on Monocrystalline Perovskite Thin Films
Xu Li Chang Liu Feng Ding Zheyi Lu Peng Gao Ziwei Huang Weiqi Dang Liqiang Zhang Xiaohui Lin Shuimei Ding Bailing Li Ying Huangfu Xiaohua Shen Bo Li Xuming Zou Yuan Liu Lei Liao Yiliu Wang Xidong Duan 《Advanced functional materials》2023,33(15):2213360
The detection of ultraviolet (UV) radiation with effective performance and robust stability is essential to practical applications. Metal halide single-crystal perovskites (ABX3) are promising next-generation materials for UV detection. The device performance of all-inorganic CsPbCl3 photodetectors (PDs) is still limited by inner imperfection of crystals grown in solution. Here wafer-scale single-crystal CsPbCl3 thin films are successfully grown by vapor-phase epitaxy method, and the as-constructed PDs under UV light illumination exhibit an ultralow dark current of 7.18 pA, ultrahigh ON/OFF ratio of ≈5.22 × 105, competitive responsivity of 32.8 A W−1, external quantum efficiency of 10867% and specific detectivity of 4.22 × 1012 Jones. More importantly, they feature superb long-term stability toward moisture and oxygen within twenty-one months, good temperature tolerances at low and high temperatures. The ability of the photodetector arrays for excellent UV light imaging is further demonstrated. 相似文献
17.
Liwei Tang Wen Weng Huaixi Chen Lina Hua Wuqian Guo Yi Liu Yu Ma Yaoyao Chen Junhua Luo Zhihua Sun 《Advanced functional materials》2023,33(22):2214858
Photoexcited pyroelectricity in ferroelectrics allows the direct conversion of light radiation into electric signal without external power source, thus paving an avenue to promote optoelectronic device performances. However, it is urgently demanded to exploit new ferroelectrics with this attribute covering ultraviolet (UV)-to-infrared (IR) region for self-powered photodetection. Herein, broadband light-induced pyroelectric effects in a new 2D perovskite-type ferroelectric, (BBA)2(EA)2Pb3Br10 (1; BBA = p-bromobenzylammonium, EA = ethylammonium), showing a high Curie temperature of 425 K and notable pyroelectric coefficient (≈5.4 × 10−3 µC cm−2 K−1) is presented. Especially, photo-induced change of its electric polarization leads to ultraviolet-to-infrared pyroelectricity in a wide spectral region (377–1950 nm). Broadband photoactivities actualized by this property break the limitation of its optical bandgap. Thus, single-crystal detectors of 1 are sensitive to UV-to-IR light with a small temperature fluctuation of 0.3 K, exhibiting a high transient responsivity up to ≈0.28 mA W−1 and specific detectivity of 1.31 × 1010 Jones under zero bias (at 405 nm); such figure-of-merits are beyond than those self-powered photodetectors using oxide ferroelectrics. It is anticipated that the findings of light-induced pyroelectricity afford a feasible strategy to assemble newly-conceptual smart photoelectric devices, such as self-powered broadband detectors. 相似文献
18.
Yilin Sun Liu Qian Dan Xie Yuxuan Lin Mengxing Sun Weiwei Li Liming Ding Tianling Ren Toms Palacios 《Advanced functional materials》2019,29(28)
Recently, several light‐stimulated artificial synaptic devices have been proposed to mimic photonic synaptic plasticity for neuromorphic computing. Here, the photoelectric synaptic plasticity based on 2D lead‐free perovskite ((PEA)2SnI4) is demonstrated. The devices show a photocurrent activation in response to a light stimulus in a neuron‐like way and exhibit several essential synaptic functions such as short‐term plasticity (STP) and long‐term plasticity (LTP) as well as their transmission based on spike frequency control. The strength of synaptic connectivity can be effectively modulated by the duration, irradiance, and wavelength of light spikes. The ternary structure of (PEA)2SnI4 causes it to possess varied photoelectric properties by composition control, which enhances the complexity and freedoms required by neuromorphic computing. The physical mechanisms of the memory effect are attributed to two distinct lifetimes of photogenerated carrier trapping/detrapping processes modulated by controlling the proportion of Sn vacancies. This work demonstrates the great potential of (PEA)2SnI4 as a platform to develop future multifunctional artificial neuromorphic systems. 相似文献
19.
Yan Wang Shidong Chen Xiaohan Cheng Wang Chen Ziyu Xiong Ziyu Lv Chunyan Wu Li Wang Guohua Zhang Xiaobo Zhu Linbao Luo Su-Ting Han 《Advanced functional materials》2024,34(3):2309807
The neuromorphic computing architecture is a promising artificial intelligence for implementing hierarchical processing, in-memory computing, event-driven operation and functional specialization in computing systems. However, current investigations mainly focus on unisensory processing without objective experience which is contrary to the flexible sensory learning capability in the human brain that can sense and process information according to the ever-changing environment. For example, a dominant paradigm for reconfigurable bio-learning features is the emotional experience. The neurotransmitter dopamine is released during arousal, influencing the vital brain functions involved in cognition, reward learning, movement and motivation. Here, the on-demand configuration of a biorealistic synaptic connection based on a 2D CaTa2O7 (CTO) device is demonstrated that can be adaptively reconfigured for a reinforcement learning purpose by the light-active resistive switching, which originated from the photon-regulated metaplasticity. The low energy consumption of 12.4 fJ endows the reinforcement learning system with high power efficiency and reliability. Finally, in-sensor computing with a CTO synapse is implemented with a filtering function to process digital data in a neuromorphic engineering manner. This work demonstrates the feasibility of 2D perovskite neuromorphic device with enhanced biological plausibility in the approaching post-Moore era. 相似文献
20.
Silvia G. Motti Manuel Kober-Czerny Marcello Righetto Philippe Holzhey Joel Smith Hans Kraus Henry J. Snaith Michael B. Johnston Laura M. Herz 《Advanced functional materials》2023,33(32):2300363
Metal halide perovskite (MHP) semiconductors have driven a revolution in optoelectronic technologies over the last decade, in particular for high-efficiency photovoltaic applications. Low-dimensional MHPs presenting electronic confinement have promising additional prospects in light emission and quantum technologies. However, the optimisation of such applications requires a comprehensive understanding of the nature of charge carriers and their transport mechanisms. This study employs a combination of ultrafast optical and terahertz spectroscopy to investigate phonon energies, charge-carrier mobilities, and exciton formation in 2D (PEA)2PbI4 and (BA)2PbI4 (where PEA is phenylethylammonium and BA is butylammonium). Temperature-dependent measurements of free charge-carrier mobilities reveal band transport in these strongly confined semiconductors, with surprisingly high in-plane mobilities. Enhanced charge-phonon coupling is shown to reduce charge-carrier mobilities in (BA)2PbI4 with respect to (PEA)2PbI4. Exciton and free charge-carrier dynamics are disentangled by simultaneous monitoring of transient absorption and THz photoconductivity. A sustained free charge-carrier population is observed, surpassing the Saha equation predictions even at low temperature. These findings provide new insights into the temperature-dependent interplay of exciton and free-carrier populations in 2D MHPs. Furthermore, such sustained free charge-carrier population and high mobilities demonstrate the potential of these semiconductors for applications such as solar cells, transistors, and electrically driven light sources. 相似文献