- 标题
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- 实验方案
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Oxide-Core Pt-Shell Electrocatalysts for PEFCs: Photochemical Preparation Using SnO <sub/>2</sub> Nanoparticles
摘要： Core-shell electrocatalyst, in which a Pt atomic layer covers a nano-size core of a different metal, is attractive in reducing Pt usage for PEFC cathode electrocatalyst. Whilst such core-shell electrocatalysts exhibit very high mass activity for oxygen reduction reaction (ORR), their cost and durability still remain as a challenge. If inexpensive and thermochemically-stable conductive oxide could be applied to the core instead of a noble metal, cost reduction and durability improvement of such core-shell electrocatalysts may be expected. In this study, we try to develop oxide-core Pt-shell electrocatalysts by directly depositing Pt on SnO2 at an atomic level via a photochemical preparation procedure. SnO2 cores with a diameter down to ca. 3 nm could be prepared by comparing various preparation procedures of SnO2 and types of fillers. Electrochemical activities of such oxide-core Pt-shell electrocatalysts are characterized and discussed.
关键词： PEFC,SnO2,photochemical preparation,Pt-shell,Core-shell electrocatalyst
更新于2025-09-23 15:21:01
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An all-solid-state lamellar-nanostructured polymer electrolyte in-situ-prepared from smectic liquid crystal for thermally stable dye-sensitized solar cells
摘要： A novel all-solid-state polymer electrolyte based on thiolate/disulfide redox couple was in-situ prepared from a lamellar-assembled liquid crystal precursor for dye-sensitized solar cells (DSSCs). The use of the thiolate/disulfide redox couple allowed the in-situ polymerization, which ensured both preservation of the lamellar nanostructure in electrolyte and sufficient interfacial contact in DSSC. Electrochemical analysis revealed that the lamellar-nanostructured electrolyte possessed charge transport ability and photovoltaic performance quite close to the liquid crystal electrolyte precursor. The resultant all-solid-state DSSCs showed a thermally stable photovoltaic performance with PCE higher than 2% from 35 to 90 °C. The method in using in-situ polymerization of nanostructured liquid crystals to prepare solid-state electrolytes shed a new light for efficient and stable all-solid-state DSSC preparation, especially in large-scale actual application.
关键词： All-solid-state polymer electrolyte,In-situ preparation,Smectic liquid crystal,Dye-sensitized solar cell
更新于2025-09-23 15:21:01
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Reference Module in Chemistry, Molecular Sciences and Chemical Engineering || Surface-Enhanced Infrared Absorption Spectroscopy
摘要： It has been well established that infrared (IR) spectroscopy is a very useful tool for the investigation of gas–solid interfaces, which provides molecular and geometrical information of adsorbed species. Such information obtained for electrode–electrolyte interfaces would be invaluable for understanding electrochemical processes. However, to record IR signals of species in the proximity of an electrode surface, a problem concerning strong IR absorption by the solvent, especially very strong absorption by water, has to be overcome. A way to do so is to minimize the path length which the IR beam has to travel through the solution.
关键词： metal film preparation,Surface-Enhanced Infrared Absorption Spectroscopy,electrochemical processes,SEIRAS,IR spectroscopy
更新于2025-09-23 15:21:01
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[IEEE 2019 IEEE 11th International Conference on Communication Software and Networks (ICCSN) - Chongqing, China (2019.6.12-2019.6.15)] 2019 IEEE 11th International Conference on Communication Software and Networks (ICCSN) - Research of All-optical Broadcast Doublet Signals Based on Semiconductor Fiber Ring Laser
摘要： Attack traceability and attribution are two of the main tasks of IT forensics. To support this, IT forensics is not limited to investigate data after the attack has taken place. Already before the attack, an optimal environment for a subsequent investigation has to be created. While this is primarily focused on ordinary logging, we propose to set both degree and characteristics of logging, based on geolocation. Thus, for conspicuous locations, more knowledge is gathered and stored in advance (georeputation). Next to this, due to the fact that the distribution of IP addresses is not static, additional information is stored to, e.g., determine the Internet service provider, which was responsible for the IP at the time the crime was committed. This additional data also contains geoinformation that can be used later to reconstruct attack routes and to identify and analyze distributed attacks. For these purposes, however, the IP localization mechanisms, i.e., the underlying method for geolocation, must be very accurate. Therefore, next to highlighting, the bene?ts of including geobased information and providing our architecture in order to do so, this publication also investigates accuracy and reliability of geoinformation and provides its own geolocation architecture and a corresponding prototype, including an evaluation.
关键词： georeputation,Attribution,preincident preparation,geolocation,IT forensics
更新于2025-09-23 15:19:57
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Design Rules to Fully Benefit From Bifaciality in Two-Terminal Perovskite/Silicon Tandem Solar Cells
摘要： Attack traceability and attribution are two of the main tasks of IT forensics. To support this, IT forensics is not limited to investigate data after the attack has taken place. Already before the attack, an optimal environment for a subsequent investigation has to be created. While this is primarily focused on ordinary logging, we propose to set both degree and characteristics of logging, based on geolocation. Thus, for conspicuous locations, more knowledge is gathered and stored in advance (georeputation). Next to this, due to the fact that the distribution of IP addresses is not static, additional information is stored to, e.g., determine the Internet service provider, which was responsible for the IP at the time the crime was committed. This additional data also contains geoinformation that can be used later to reconstruct attack routes and to identify and analyze distributed attacks. For these purposes, however, the IP localization mechanisms, i.e., the underlying method for geolocation, must be very accurate. Therefore, next to highlighting, the bene?ts of including geobased information and providing our architecture in order to do so, this publication also investigates accuracy and reliability of geoinformation and provides its own geolocation architecture and a corresponding prototype, including an evaluation.
关键词： geolocation,preincident preparation,Attribution,IT forensics,georeputation
更新于2025-09-23 15:19:57
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Current trends in laser-induced breakdown spectroscopy: a tutorial review
摘要： The purpose of this tutorial article is to provide a brief update on the advances available for laser-induced breakdown spectroscopy (LIBS), focusing broad experimental and instrumental possibilities. Due to the inherent versatility of LIBS, this technique can be elegantly applied to various applications. However, during the method development one should have prior knowledge about its analytical limitations in order to obtain reliable results. In the present review, we summarize key analytical variables required for proper sample treatment, analytical signal enhancement, data processing, qualitative and quantitative approaches as well as recent research and developments using LIBS. Remarkable analytical advances have recently been proposed for LIBS and raised its analytical performance to a level never reached before. Most prominent perhaps, have been the development of many nontraditional calibration approaches based on transition atomic energies (emission wavelengths), the use of a single standard for calibration, increase of the ablated sample mass (accumulated laser pulses), and even overcoming severe LIBS problems such as the matrix effects.
关键词： LIBS,signal enhancement,calibration,qualitative analysis,data processing,sample preparation
更新于2025-09-23 15:19:57
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Phytochemical properties and antioxidant activity of Echinops persicus plant extract: green synthesis of carbon quantum dots from the plant extract
摘要： Echinops persicus is a species of Echinops that can be found in Europe and western Asia especially in Iran. In this paper, the phytochemical properties of Echinops persicus were thoroughly investigated and studied. In this way, total amounts of flavonoid, tannins, phenols, carotenoids, saponins, alkaloids, and anthocyanin were measured by various analytical methods. The major phenolic and flavonoid content was found in the root acetone and flower ethanolic extract of the plant. Also, major saponins and carotenoid contents was found in root and leaf of the plant. These measurements were also performed for root, leaf, and flower of the plant in various solvent extracts. The results indicated that Echinops persicus is a rich source of secondary metabolites. Also, the plant extract demonstrated a considerable antiradical activity, which evaluated qualitatively as well as quantitatively. The largest capacity to neutralize DPPH radicals was found for root water extract of Echinops persicus plant. Finally, the possibility of the plant extract was evaluated for the green preparation of carbon quantum dots (CQDs). As-prepared CQDs were characterized by TEM, HRTEM, UV–Vis, XRD, and EDX analyses.
关键词： Antioxidant,Echinops persicus,Secondary metabolites,Green preparation of CQDs,Carbon quantum dots
更新于2025-09-23 15:19:57
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Ultrafast Response Polyelectrolyte Humidity Sensor for Respiration Monitoring
摘要： Respiration monitoring is important for evaluating human health. Humidity sensing is a promising way to establish a relationship between human respiration and electrical signal. This work describes polymer humidity sensors with ultrafast response for respiration monitoring. The humidity-sensitive polyelectrolyte is in situ crosslinked on the substrate printed with interdigitated electrodes by a thiol-ene click reaction. The polyelectrolyte humidity sensor owns rapid water adsorption/desorption ability, excellent stability and repeatability. The sensor with ultrafast response and recovery (0.29 s/0.47 s) when changing humidity between 33% and 95% shows good application prospects in breath monitoring and touchless sensing. Different respiration patterns can be distinguished and the breath rate/depth of detection subjects can also be determined by the sensor. In addition, the obtained sensor can sense the skin evaporation by a non-contact way.
关键词： breath monitoring,in situ preparation,ultrafast response,click reaction,polyelectrolyte humidity sensors
更新于2025-09-19 17:15:36
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Alkylamine-mediated synthesis and photocatalytic properties of ZnO
摘要： A simple approach to synthesize ZnO microstructures was reported using dodecylamine, hexadecylamine and oleylamine as template agents. The synthesized ZnO was characterized by XRD, FESEM, TEM, EDS mapping, FTIR, UV-vis DRS, Raman spectroscopy and BET analysis. Hierarchical oriented ZnO microstructures were obtained. The photocatalytic performance of ZnO prepared with different types of alkylamines was evaluated by the degradation of methylene blue (MB) and methyl orange (MO). The results suggested that alkylamine control the nucleation, growth and morphology of ZnO. The photocatalytic properties of ZnO on the degradation of MB and MO decreased with increasing the alkyl chain length in alkylamine.
关键词： photocatalytic property,controlled preparation,ZnO,alkylamine
更新于2025-09-19 17:15:36
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Na incorporation controlled single phase kesterite Cu2ZnSnS4 solar cell material
摘要： It is theoretically and experimentally challenging to fabricate single phase Cu2ZnSnS4 (CZTS) and more difficult to synthesize it by sol-gel method. Theoretical work reveals that Na can passivate the dangling bonds in the grain boundaries of CZTS and thus enhance the photovoltaic performance. Therefore, Na incorporation may be an effective way in passivating defects in CZTS films and fabricating CZTS with high quality and single phase. In this study, we will try to incorporate Na into CZTS films by sol-gel method to help passivate defects in CZTS and achieve single phase kesterite CZTS films using a different solvent 2-methoxybutanol. Different Na/(Cu+Zn+Sn) atomic ratios (0%-3%) will be employed. Through controlling Na incorporation amount in solution, we can prevent the generation of other phases like SnO2 and a pure single phase kesterite CZTS can be achieved. The optical band gap of the optimal CZTS film is 1.24 eV. All Na doped CZTS films show p-type conduction behavior.
关键词： Solar energy materials,Sol-gel preparation,Crystal structure
更新于2025-09-19 17:13:59