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Sunny MM, Thamankar R. Spike rate dependent synaptic characteristics in lamellar, multilayered alpha-MoO 3 based two-terminal devices - efficient way to control the synaptic amplification. RSC Adv 2024; 14:2518-2528. [PMID: 38226148 PMCID: PMC10788777 DOI: 10.1039/d3ra07757h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Accepted: 12/19/2023] [Indexed: 01/17/2024] Open
Abstract
Brain-inspired computing systems require a rich variety of neuromorphic devices using multi-functional materials operating at room temperature. Artificial synapses which can be operated using optical and electrical stimuli are in high demand. In this regard, layered materials have attracted a lot of attention due to their tunable energy gap and exotic properties. In the current study, we report the growth of layered MoO3 using the chemical vapor deposition (CVD) technique. MoO3 has an energy gap of 3.22 eV and grows with a large aspect ratio, as seen through optical and scanning electron microscopy. We used transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy for complete characterisation. The two-terminal devices using platinum (Pt/MoO3/Pt) exhibit superior memory with the high-resistance state (HRS) and low-resistance state (LRS) differing by a large resistance (∼MΩ). The devices also show excellent synaptic characteristics. Both optical and electrical pulses can be utilised to stimulate the synapse. Consistent learning (potentiation) and forgetting (depression) curves are measured. Transition from long term depression to long term potentiation can be achieved using the spike frequency dependent pulsing scheme. We have found that the amplification of postsynaptic current can be tuned using such frequency dependent spikes. This will help us to design neuromorphic devices with the required synaptic amplification.
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Affiliation(s)
- Meenu Maria Sunny
- Department of Physics, Vellore Institute of Technology Vellore TN India
- Centre for Functional Materials, Vellore Institute of Technology Vellore TN India
| | - R Thamankar
- Centre for Functional Materials, Vellore Institute of Technology Vellore TN India
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Tran DM, Son JW, Ju TS, Hwang C, Park BH. Dopamine-Regulated Plasticity in MoO 3 Synaptic Transistors. ACS APPLIED MATERIALS & INTERFACES 2023; 15:49329-49337. [PMID: 37819637 DOI: 10.1021/acsami.3c06866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/13/2023]
Abstract
Field-effect transistor-based biosensors have gained increasing interest due to their reactive surface to external stimuli and the adaptive feedback required for advanced sensing platforms in biohybrid neural interfaces. However, complex probing methods for surface functionalization remain a challenge that limits the industrial implementation of such devices. Herein, a simple, label-free biosensor based on molybdenum oxide (MoO3) with dopamine-regulated plasticity is demonstrated. Dopamine oxidation facilitated locally at the channel surface initiates a charge transfer mechanism between the molecule and the oxide, altering the channel conductance and successfully emulating the tunable synaptic weight by neurotransmitter activity. The oxygen level of the channel is shown to heavily affect the device's electrochemical properties, shifting from a nonreactive metallic characteristic to highly responsive semiconducting behavior. Controllable responsivity is achieved by optimizing the channel's dimension, which allows the devices to operate in wide ranges of dopamine concentration, from 100 nM to sub-mM levels, with excellent selectivity compared with K+, Na+, and Ca2+.
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Affiliation(s)
- Duc Minh Tran
- Division of Quantum Phases and Devices, Department of Physics, Konkuk University, Seoul 05029, Republic of Korea
| | - Jong Wan Son
- Division of Quantum Phases and Devices, Department of Physics, Konkuk University, Seoul 05029, Republic of Korea
- Quantum Spin Team, Korea Research Institute of Standards and Science, Daejeon 34113, Republic of Korea
| | - Tae-Seong Ju
- Quantum Spin Team, Korea Research Institute of Standards and Science, Daejeon 34113, Republic of Korea
| | - Chanyong Hwang
- Quantum Spin Team, Korea Research Institute of Standards and Science, Daejeon 34113, Republic of Korea
| | - Bae Ho Park
- Division of Quantum Phases and Devices, Department of Physics, Konkuk University, Seoul 05029, Republic of Korea
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3
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Chen H, Blatnik MA, Ritterhoff CL, Sokolović I, Mirabella F, Franceschi G, Riva M, Schmid M, Čechal J, Meyer B, Diebold U, Wagner M. Water Structures Reveal Local Hydrophobicity on the In 2O 3(111) Surface. ACS NANO 2022; 16:21163-21173. [PMID: 36449748 PMCID: PMC9798908 DOI: 10.1021/acsnano.2c09115] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 11/17/2022] [Indexed: 06/17/2023]
Abstract
Clean oxide surfaces are generally hydrophilic. Water molecules anchor at undercoordinated surface metal atoms that act as Lewis acid sites, and they are stabilized by H bonds to undercoordinated surface oxygens. The large unit cell of In2O3(111) provides surface atoms in various configurations, which leads to chemical heterogeneity and a local deviation from this general rule. Experiments (TPD, XPS, nc-AFM) agree quantitatively with DFT calculations and show a series of distinct phases. The first three water molecules dissociate at one specific area of the unit cell and desorb above room temperature. The next three adsorb as molecules in the adjacent region. Three more water molecules rearrange this structure and an additional nine pile up above the OH groups. Despite offering undercoordinated In and O sites, the rest of the unit cell is unfavorable for adsorption and remains water-free. The first water layer thus shows ordering into nanoscopic 3D water clusters separated by hydrophobic pockets.
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Affiliation(s)
- Hao Chen
- Institute
of Applied Physics, TU Wien, 1040Vienna, Austria
- State
Key Laboratory of Catalysis, Dalian Institute
of Chemical Physics, Chinese Academy of Sciences, Dalian116023, China
- University
of the Chinese Academy of Sciences, Beijing100049, China
| | - Matthias A. Blatnik
- Institute
of Applied Physics, TU Wien, 1040Vienna, Austria
- Central
European Institute of Technology (CEITEC), Brno University of Technology, 61200Brno, Czech
Republic
| | - Christian L. Ritterhoff
- Interdisciplinary
Center for Molecular Materials (ICMM) and Computer Chemistry Center
(CCC), Friedrich-Alexander-Universität
Erlangen-Nürnberg (FAU), 91052Erlangen, Germany
| | - Igor Sokolović
- Institute
of Applied Physics, TU Wien, 1040Vienna, Austria
| | | | | | - Michele Riva
- Institute
of Applied Physics, TU Wien, 1040Vienna, Austria
| | - Michael Schmid
- Institute
of Applied Physics, TU Wien, 1040Vienna, Austria
| | - Jan Čechal
- Central
European Institute of Technology (CEITEC), Brno University of Technology, 61200Brno, Czech
Republic
| | - Bernd Meyer
- Interdisciplinary
Center for Molecular Materials (ICMM) and Computer Chemistry Center
(CCC), Friedrich-Alexander-Universität
Erlangen-Nürnberg (FAU), 91052Erlangen, Germany
| | - Ulrike Diebold
- Institute
of Applied Physics, TU Wien, 1040Vienna, Austria
| | - Margareta Wagner
- Institute
of Applied Physics, TU Wien, 1040Vienna, Austria
- Central
European Institute of Technology (CEITEC), Brno University of Technology, 61200Brno, Czech
Republic
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4
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Jia W, Li W, Zhao X, Feng Y, Zuo M, Sun Y, Tang X, Zeng X, Lin L. Insights into the catalytic mechanism of 5-hydroxymethfurfural to phthalic anhydride with MoO 3/Cu(NO 3) 2 in one-pot. Catal Sci Technol 2021. [DOI: 10.1039/d1cy00940k] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
A synthetic approach to obtain renewable phthalic anhydride (PA) from 5-hydroxymethfurfural (HMF) with a yield of 63.2% using MoO3/Cu(NO3)2 as a catalyst in one pot.
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Affiliation(s)
- Wenlong Jia
- Xiamen Key Laboratory of Clean and High-valued Utilization for Biomass
- College of Energy
- Xiamen University
- Xiamen
- P. R. China
| | - Weile Li
- Xiamen Key Laboratory of Clean and High-valued Utilization for Biomass
- College of Energy
- Xiamen University
- Xiamen
- P. R. China
| | - Xiaoyu Zhao
- Xiamen Key Laboratory of Clean and High-valued Utilization for Biomass
- College of Energy
- Xiamen University
- Xiamen
- P. R. China
| | - Yunchao Feng
- Xiamen Key Laboratory of Clean and High-valued Utilization for Biomass
- College of Energy
- Xiamen University
- Xiamen
- P. R. China
| | - Miao Zuo
- College of Forestry
- Hebei Agricultural University
- Baoding
- P. R. China
| | - Yong Sun
- Xiamen Key Laboratory of Clean and High-valued Utilization for Biomass
- College of Energy
- Xiamen University
- Xiamen
- P. R. China
| | - Xing Tang
- Xiamen Key Laboratory of Clean and High-valued Utilization for Biomass
- College of Energy
- Xiamen University
- Xiamen
- P. R. China
| | - Xianhai Zeng
- Xiamen Key Laboratory of Clean and High-valued Utilization for Biomass
- College of Energy
- Xiamen University
- Xiamen
- P. R. China
| | - Lu Lin
- Xiamen Key Laboratory of Clean and High-valued Utilization for Biomass
- College of Energy
- Xiamen University
- Xiamen
- P. R. China
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A dual-carrier adsorbate-modulated surface conductance model better captures the thermal dependence of conductance in TiO2 and MoO3 powders than an inter-grain hopping model. REACTION KINETICS MECHANISMS AND CATALYSIS 2020. [DOI: 10.1007/s11144-020-01833-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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6
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Ma H, Fang H, Wu W, Zheng C, Wu L, Wang H. A highly transparent humidity sensor with fast response speed based on α-MoO 3 thin films. RSC Adv 2020; 10:25467-25474. [PMID: 35518604 PMCID: PMC9055238 DOI: 10.1039/d0ra03958f] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Accepted: 06/29/2020] [Indexed: 12/20/2022] Open
Abstract
Metal oxide based humidity sensors are important indicators in environmental monitoring. However, most of them are non-transparent and have a long response time, which cannot meet the application of real-time humidity sensing in transparent electronics. Here, we report a metal oxide humidity sensor based on chemically synthesized molybdenum oxide (α-MoO3) thin films. By a green reaction in an ice water bath, the stable precursor containing nanocrystalline colloids was obtained. Molybdenum oxide films with controllable morphology were fabricated through one-step spin coating. The α-MoO3 based humidity sensor exhibits extremely high transparency (85%) in the visible region and has short response and recovery times (0.97 and 12.11 s). In addition, it also shows high sensitivity, good logarithmic linearity and selectivity in a wide relative humidity range of 11% to 95%. The mechanism of humidity sensing was further studied by complex impedance spectroscopy. This novel metal oxide humidity sensor combined with high transparency and fast response speed is expected to broaden the application ranges of humidity sensors.
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Affiliation(s)
- Hailong Ma
- State Key Laboratory for Mechanical Behavior of Materials, School of Material Science and Engineering, Xi'an Jiaotong University Xi'an 710049 China
| | - Huajing Fang
- State Key Laboratory for Mechanical Behavior of Materials, School of Material Science and Engineering, Xi'an Jiaotong University Xi'an 710049 China
| | - Wenting Wu
- State Key Laboratory for Mechanical Behavior of Materials, School of Material Science and Engineering, Xi'an Jiaotong University Xi'an 710049 China
| | - Cheng Zheng
- School of Electronic and Information Engineering, State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University Xi'an 710049 China
| | - Liangliang Wu
- School of Electronic and Information Engineering, State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University Xi'an 710049 China
| | - Hong Wang
- Department of Materials Science and Engineering, Shenzhen Engineering Research Center for Novel Electronic Information Materials and Devices, Southern University of Science and Technology Shenzhen 518055 China
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