scholarly journals Effect of Heating Rate on the Photocatalytic Activity of Ag–TiO2 Nanocomposites by One-Step Process via Aerosol Routes

Catalysts ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 17
Author(s):  
Kusdianto Kusdianto ◽  
Meditha Hudandini ◽  
Dianping Jiang ◽  
Masaru Kubo ◽  
Manabu Shimada
Keyword(s):  
Photocatalytic Activity ◽  
Heating Rate ◽  
Surface Area ◽  
Vapor Deposition ◽  
Physical Vapor Deposition ◽  
Uv Light ◽  
Total Pore Volume ◽  
Nanocomposite Films ◽  
Heating Rates ◽  
One Step

Ag–TiO2 nanocomposite films, based of Ag and TiO2 nanoparticles, were fabricated in a one-step aerosol route employing the simultaneous plasma-enhanced chemical vapor deposition and physical vapor deposition systems. The as-fabricated films were subjected to different heating rates (3 to 60 °C/min) with a constant annealing temperature of 600 °C to observe the significant changes in the properties (e.g., nanoparticle size, crystalline size, crystallite phase, surface area) toward the photocatalytic performance. The photocatalytic activity was evaluated by the measurement of the degradation of a methylene blue aqueous solution under UV light irradiation, and the results revealed that it gradually increased with the increase in the heating rate, caused by the increased Brunauer–Emmett–Teller (BET) specific surface area and total pore volume.

Sol-gel synthesis, characterisation, and photocatalytic activity of porous spinel Co3O4 nanosheets

2014 ◽  
Vol 68 (8) ◽  
Author(s):  
Manoj Pudukudy ◽  
Zahira Yaakob
Keyword(s):  
Electron Microscopy ◽  
Photocatalytic Activity ◽  
Surface Area ◽  
Uv Light ◽  
Average Pore Size ◽  
Sol Gel ◽  
Spherical Particles ◽  
Cubic Phase ◽  
Face Centered Cubic ◽  
Oriented Growth

AbstractMesoporous spinel Co3O4 nanosheets were synthesised via a simple sol-gel route using the Pluronic P123 triblock copolymer as the stabilising agent. Their structural, morphological, and textural properties were characterised. FTIR spectrum revealed the formation of cobalt oxide without any surface adsorbed impurities. Face centered cubic phase of spinel Co3O4 with the mean crystalline size of 26 nm was assigned by the X-ray diffraction analysis without the formation of other phases. Porous nanosheets and cave-like morphologies were identified from the scanning electron microscopy (SEM) images. Highly agglomerated more or less spherical particles with well separated lattice fringes, representing the oriented growth of nanocrystals, were noticed on the transmission electron microscopy photographs. Surface area analysis revealed that the spinel has high surface area of about 25 m2 g−1 with monomodal mesoporosity. The average pore size distribution was found to be about 15.8 nm. The as-prepared spinel photocatalyst showed a mild photocatalytic activity in the degradation of methylene blue (2.5 mg L−1) under UV light irradiation with air as the oxidising agent. Photocatalytic activity of the as-prepared reusable Co3O4 was found to be higher than that of the commercial spinel powder.

scholarly journals Light- and magnetically actuated FePt microswimmers

2021 ◽  
Vol 44 (6) ◽  
Author(s):  
Vincent Mauricio Kadiri ◽  
Jan-Philipp Günther ◽  
Sai Nikhilesh Kottapalli ◽  
Rahul Goyal ◽  
Florian Peter ◽  
...  
Keyword(s):  
Vapor Deposition ◽  
Physical Vapor Deposition ◽  
Deposition Process ◽  
Biological Research ◽  
Rotating Magnetic Fields ◽  
Magnetically Actuated ◽  
Catalytically Active ◽  
One Step ◽  
Hard Magnetic Properties ◽  
Physical Vapor Deposition Process

AbstractExternally controlled microswimmers offer prospects for transport in biological research and medical applications. This requires biocompatibility of the swimmers and the possibility to tailor their propulsion mechanisms to the respective low Reynolds number environment. Here, we incorporate low amounts of the biocompatible alloy of iron and platinum (FePt) in its $$\hbox {L1}_{{0}}$$ L1 0 phase in microstructures by a versatile one-step physical vapor deposition process. We show that the hard magnetic properties of $$\hbox {L1}_{{0}}$$ L1 0 FePt are beneficial for the propulsion of helical micropropellers with rotating magnetic fields. Finally, we find that the FePt coatings are catalytically active and also make for Janus microswimmers that can be light-actuated and magnetically guided.

One step synthesis of efficient photocatalysts by TCAP doped g-C3N4 for enhanced visible-light photocatalytic activity

2020 ◽  
Vol 44 (3) ◽  
pp. 1127-1137 ◽  
Author(s):  
Hao Wu ◽  
Yaoxing Huo
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Surface Area ◽  
Light Absorption ◽  
Defect Structure ◽  
Charge Carriers ◽  
Visible Light Absorption ◽  
Efficient Separation ◽  
One Step ◽  
Visible Light Photocatalytic

CN/TCAP with enhanced visible light absorption, large surface area and defect structure allow efficient separation of charge carriers.

A high-performance fully nanostructured individual CdSe nanotube photodetector with enhanced responsivity and photoconductive gain

2017 ◽  
Vol 5 (28) ◽  
pp. 7057-7066 ◽  
Author(s):  
Qinwei An ◽  
Xianquan Meng ◽  
Ke Xiong ◽  
Yunlei Qiu
Keyword(s):  
Vapor Deposition ◽  
Physical Vapor Deposition ◽  
High Performance ◽  
Ambient Pressure ◽  
Volume Ratio ◽  
Deposition Process ◽  
Single Crystalline ◽  
Photoconductive Gain ◽  
One Step ◽  
Physical Vapor Deposition Process

Single-crystalline CdSe nanotubes with a perfect hollow tubular architecture and higher surface-to-volume ratio were synthesized via a simplified one-step ambient pressure physical vapor deposition process and utilized to fabricate an individual CdSe nanotube photodetector with enhanced responsivity and photoconductive gain.

scholarly journals Green synthesis of carbon-supported nanoparticle catalysts by physical vapor deposition on soluble powder substrates

2015 ◽  
Vol 5 (1) ◽  
Author(s):  
Hee-Young Park ◽  
Injoon Jang ◽  
Namgee Jung ◽  
Young-Hoon Chung ◽  
Jaeyune Ryu ◽  
...  
Keyword(s):  
Surface Area ◽  
Vapor Deposition ◽  
Physical Vapor Deposition ◽  
Metal Oxide Nanoparticles ◽  
High Surface ◽  
High Surface Area ◽  
Carbon Support ◽  
Carbon Supports ◽  
Bulk Materials ◽  
Stabilizing Effect

Abstract Metal and metal oxide nanoparticles (NPs) supported on high surface area carbon (NP/Cs) were prepared by the physical vapor deposition of bulk materials on an α-D-glucose (Glu) substrate, followed by the deposition of the NPs on carbon supports. Using Glu as a carrier for the transport of NPs from the bulk materials to the carbon support surfaces, ultrafine NPs were obtained, exhibiting a stabilizing effect through OH moieties on the Glu surfaces. This stabilizing effect was strong enough to stabilize the NPs, but weak enough to not significantly block the metal surfaces. As only the target materials and Glu are required in our procedure, it can be considered environmentally friendly, with the NPs being devoid of hazardous chemicals. Furthermore, the resulting NP/Cs exhibited an improvement in activity for various electrochemical reactions, mainly attributed to their high surface area.

HEATING RATE PREDICTION FOR INDUCTION WELDING MAGNETIC SUSCEPTORS

2021 ◽  
Author(s):  
ROMAIN G. MARTIN ◽  
CHRISTER JOHANSSON ◽  
JASON R. TAVARES ◽  
MARTINE DUBÉ
Keyword(s):  
Magnetic Field ◽  
Heating Rate ◽  
Surface Area ◽  
Magnetic Particles ◽  
Eddy Currents ◽  
Field Amplitude ◽  
Hysteresis Curve ◽  
Heating Rates ◽  
Electrically Conductive ◽  
Thermoplastic Matrix

Induction welding involves generating heat by applying an oscillating magnetic field, which produces eddy currents and Joule losses in an electrically-conductive material or hysteresis losses in a magnetic material. Most applications rely on eddy currents generation as composites are often made of electrically-conductive carbon fibres. However, in other applications, heat can be produced by a magnetic susceptor located at the weld interface of the parts to be joined. Composite films of magnetic particles dispersed in a thermoplastic matrix can serve as magnetic susceptors. Magnetic particles selection relies on various parameters that must be thoroughly defined beforehand. Firstly, the applied magnetic field amplitude and frequency is calculated, based on the generated current and the induction coil geometry. Secondly, the thermoplastic matrix is characterized, mainly with DSC measurements, to define its processing window. Finally, the magnetic properties of the particles are measured – for instance using a vibrating sample magnetometer (VSM) – to obtain the hysteresis curve for the applied field. The enclosed surface area of the hysteresis curve (i.e. absorbed energy density) is critical, as low hysteresis materials (i.e. soft magnets) will not dissipate enough heat, while high hysteresis materials (i.e. hard magnets) cannot be fully exploited as the saturation hysteresis is not reached within the used field amplitude. A methodology to approximate the hysteresis enclosed surface area with limited data is proposed, helping to anticipate the heating rate of a susceptor candidate material. Based on these parameters, the theoretical heating rates of three magnetic susceptor materials (magnetic particles of iron, nickel and magnetite) for induction welding are calculated. They are verified experimentally by comparing with the hysteresis analysis and by measuring the temperature evolution of samples made of polypropylene containing the magnetic particles.

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