Modeling Interfacial Interaction between Gas Molecules and Semiconductor Metal Oxides: A New View Angle on Gas Sensing

Advanced Science, Год журнала: 2022, Номер 9(33)

Опубликована: Сен. 18, 2022

Abstract With the development of internet things and artificial intelligence electronics, metal oxide semiconductor (MOS)‐based sensing materials have attracted increasing attention from both fundamental research practical applications. MOS possess intrinsic physicochemical properties, tunable compositions, electronic structure, are particularly suitable for integration miniaturization in developing chemiresistive gas sensors. During processes, dynamic gas–solid interface interactions play crucial roles improving sensors’ performance, most studies emphasize gas–MOS chemical reactions. Herein, a new view angle focusing more on physical during sensing, basic theory overview latest progress process molecules including adsorption, desorption, diffusion, systematically summarized elucidated. The unique mechanisms also discussed various aspects molecular interaction models, diffusion mechanism, interfacial reaction behaviors, where structure–activity relationship behavior overviewed detail. Especially, surface adsorption–desorption dynamics evaluated, their potential effects performance elucidated regulation perspective. Finally, prospect further directions processes sensors is discussed, aiming to supplement approaches high‐performance

Язык: Английский

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Metal and Metal Oxide Supported on Ordered Mesoporous Carbon as Heterogeneous Catalysts

ACS Catalysis, Год журнала: 2023, Номер 13(7), С. 4060 - 4090

Опубликована: Март 9, 2023

The evolution of model catalyst systems has experienced single-crystal surfaces different transition metals and crystal faces, two-dimensional with nanoparticles (NPs) deposited on a flat support surface, three-dimensional NPs loaded into the high-surface-area supports such as ordered mesoporous materials. latter two mimic nanoparticle properties in industrial catalysts. Ordered carbon (OMC) materials play unparalleled roles catalysis, energy storage, adsorption, chromatographic separation, etc. because their distinctive structure which allows Knudsen diffusion inside mesopores, dispersion oxides, embedment pore walls. In this review, synthesis routes OMC-supported metal or oxide catalysts, including hard-templating soft-templating methods, are briefly introduced. Mass transfer reactant chemisorption metals, discrimination active species, catalytic reaction mechanism catalysts systemically summarized, highlight advantages catalysis occurring mesopores. Understanding these molecular-dominated factors provides insight controlling highly selective reactions and, therefore, design long life.

Язык: Английский

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Synergistic Effect of Electron Scattering and Space Charge Transfer Enabled Unprecedented Room Temperature NO₂ Sensing Response of SnO₂

Small, Год журнала: 2023, Номер 19(48)

Опубликована: Июль 4, 2023

Metal oxide gas sensors have long faced the challenge of low response and poor selectivity, especially at room temperature (RT). Herein, a synergistic effect electron scattering space charge transfer is proposed to comprehensively improve sensing performance n-type metal oxides toward oxidizing NO2 (electron acceptor) RT. To this end, porous SnO2 nanoparticles (NPs) assembled from grains about 4 nm with rich oxygen vacancies are developed through an acetylacetone-assisted solvent evaporation approach combined precise N2 air calcinations. The results show that as-fabricated NPs sensor exhibits unprecedented -sensing performance, including outstanding (Rg /Ra = 772.33 @ 5 ppm), fast recovery (<2 s), extremely detection limit (10 ppb), exceptional selectivity (response ratio >30) Theoretical calculation experimental tests confirm excellent mainly attributed unique transfer. This work proposes useful strategy for developing high-performance RT using oxides, provides in-depth understanding basic characteristics on sensing, paving way efficient power consumption

Язык: Английский

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Ultrathin two-dimensional materials: New opportunities and challenges in ultra-sensitive gas sensing

Coordination Chemistry Reviews, Год журнала: 2024, Номер 505, С. 215691 - 215691

Опубликована: Янв. 31, 2024

Язык: Английский

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Increasing the Catalytic Activity of Co₃O₄ via Boron Doping and Chemical Reduction for Enhanced Acetone Detection

Advanced Functional Materials, Год журнала: 2024, Номер 34(18)

Опубликована: Янв. 14, 2024

Abstract Optimally increasing the catalytic activity of Co 3 O 4 ‐based materials is crucial for promoting their practical applications acetone detection; however, this still remains challenging. Herein, a strategy proposed in work to increase toward oxidation through synergistic effect boron doping and chemical reduction, which can substantially improve sensing performance detection. The characterization results confirm that present facilitates formation more oxygen vacancies increases content 2+ ions serving as active sites. As expected, optimal sensor yields higher response . To extend application auxiliary diagnosis diabetes exhaled breath, sensors distinguished between concentrations breath healthy individuals simulated patients with diabetes. Detailed gas‐sensing measurements reveal enhanced attributed increased by Mars–van Krevelen, Langmuir–Hinshelwood, Eley–Rideal mechanisms. This study provides new insights into fabrication high‐performance metal oxide‐based gas improving materials.

Язык: Английский

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Pt‐Pd Nanoalloys Functionalized Mesoporous SnO₂ Spheres: Tailored Synthesis, Sensing Mechanism, and Device Integration

Small, Год журнала: 2023, Номер 19(39)

Опубликована: Июнь 1, 2023

Abstract Methane (CH 4 ), as the vital energy resource and industrial chemicals, is highly flammable explosive for concentrations above limit, triggering potential risks to personal production safety. Therefore, exploiting smart gas sensors real‐time monitoring of CH becomes extremely important. Herein, Pt‐Pd nanoalloy functionalized mesoporous SnO 2 microspheres (Pt‐Pd/SnO ) were synthesized, which show uniform diameter (≈500 nm), high surface area (40.9–56.5 m g −1 large mesopore size (8.8–15.8 nm). The dispersed nanoalloys are confined in mesopores , causing generation ofoxygen defects increasing carrier concentration sensitive materials. representative Pt 1 ‐Pd /SnO exhibits superior sensing performance with ultrahigh response ( R a /R = 21.33 3000 ppm), fast response/recovery speed (4/9 s), well outstanding stability. Spectroscopic analyses imply that such an excellent process involves conversion into formic acid CO intermediates, finally . Density functional theory (DFT) calculations reveal attractive covalent bonding interaction rapid electron transfer between support, dramatically promote orbital hybridization Pd sites adsorbed molecules, enhancing catalytic activation over layer.

Язык: Английский

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Reconfigurable Manipulation of Oxygen Content on Metal Oxide Surfaces and Applications to Gas Sensing

ACS Nano, Год журнала: 2023, Номер 17(18), С. 17790 - 17798

Опубликована: Авг. 23, 2023

Oxygen vacancies and adsorbed oxygen species on metal oxide surfaces play important roles in various fields. However, existing methods for manipulating surface require severe settings are ineffective repetitive manipulation. We present a method to manipulate the amount of by modifying adsorption energy electrically controlling electron concentration oxide. The control ability is verified using first-principles calculations based density functional theory (DFT), X-ray photoelectron spectroscopy (XPS), electrical resistance analysis. presented implemented fabricating thin film transistors with embedded microheaters. can reconfigure In2O3, SnO2, IGZO so that specific chemisorption dominates. selectively increase oxidizing (e.g., NO NO) reducing gas H2S, NH3, CO) reactions be vacancy-rich or species-rich. proposed applied sensors overcomes their limitations. makes sensor insensitive one H2S) mixed-gas environments NO2+H2S) provides linear response (R2 = 0.998) target NO2) within 3 s. believe applicable applications utilizing surfaces.

Язык: Английский

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Polyoxometalates-based functional materials in chemiresistive gas sensors and electrochemical sensors

TrAC Trends in Analytical Chemistry, Год журнала: 2023, Номер 167, С. 117233 - 117233

Опубликована: Авг. 20, 2023

Язык: Английский

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3D Porous MXene Nanosheet/SnO₂ Nanoparticle Composites for H₂S Gas Sensing

ACS Applied Nano Materials, Год журнала: 2024, Номер 7(5), С. 5442 - 5453

Опубликована: Фев. 27, 2024

Due to the large band gap, most metal oxide semiconductor (MOS)-based gas sensors operate at high temperatures, which greatly limits their performance for sensing. In this work, we reported successful synthesis of nanocomposites consisting porous MXene nanosheets formed by sublimation sulfur and SnO2 nanoparticles (S-PM/SnO2). To prevent restacking flakes under van der Waals force, a sacrificial S-template method was employed transform into three-dimensional (3D) structure. The presence lowers operating temperature. With response (∼30.6 – 10 ppm H2S), rapid speed (∼16.6 s 50 sensitivity (∼3.12 ppm–1), low detection (distinct 100 ppb good selectivity °C, sensor based on optimal sample S-PM/SnO2-6 demonstrates excellent H2S sensing performance. improvement in gas-sensing capacity can be attributed development heterojunctions interface (S-PM) (NPs). This leads an enlarged surface depletion region elevated potential barrier, significantly amplifies range resistance variation. These results suggest that S-PM/SnO2 nanocomposite has promising prospects realm low-temperature highly sensitive detection.

Язык: Английский

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Loose Ag-Doped LaFeO₃ Nanotubes-Based Gas Sensor for Excellent Acetic Acid Sensing

IEEE Sensors Journal, Год журнала: 2024, Номер 24(5), С. 5821 - 5829

Опубликована: Янв. 12, 2024

The efficient and reliable monitoring of acetic acid (CH3COOH) is significant to environmental protection human healthcare. LaFeO3 a potential sensing material for CH3COOH with its good sensitivity high plasticity. To further improve the properties meet requirements applications, we successfully utilized facile electrospinning technique fabricate series CH3COOH-sensitive Ag-doped (0–5 mol%) nanotubes. systematic characterization shows that appropriate content (4 Ag doping can effectively ameliorate morphology realize loose porous structures. Meanwhile, sensitization effect ameliorated significantly enhance gas-sensing vapor. optimal nanotubes-based gas sensor results in detection limit 0.5 ppm 3.6-fold enhancement response 100-ppm compared pure compact nanotubes at low operating temperature (150 °C). It also exhibits excellent selectivity long-term stability. Therefore, be regarded as promising practical applications. Finally, mechanism enhanced discussed.

Язык: Английский

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