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Recent Development of Photocatalysts Containing Carbon Species: A Review
摘要： Undoubtedly, carbon-based (nano)composites can be promising photocatalysts with improved photocatalytic activity due to the coupling effect from the incorporation of carbon species. In this mini-review, we focus on the recent development of photocatalysts based on carbon-based (nano)composites. TiO2 is well-known as a typical photocatalyst. Special attention is paid to the various types of carbon–TiO2 composites such as C-doped TiO2, N–C-doped TiO2, metal–C-doped TiO2, and other co-doped C/TiO2 composites. Various synthetic strategies including the solvothermal/hydrothermal method, sol–gel method, and template-directed method are reviewed for the preparation of carbon-based TiO2 composites. C/graphitic carbon nitride (g-C3N4) composites and ternary C-doped composites are also summarized and ascribed to the unique electronic structure of g-C3N4 and the synergistic effect of the ternary interfaces, respectively. In the end, we put forward the future perspective of the photocatalysts containing carbon species based on our knowledge.
关键词： (nano)composites,synergistic effect,g-C3N4,C-doped,photocatalysts,TiO2
更新于2025-09-23 15:22:29
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Charge Transfer Tuned by the Surrounding Dielectrics in TiO2-Ag Composite Arrays
摘要： TiO2/Ag bilayer ?lms sputtered onto a 2D polystyrene (PS) bead array in a magnetron sputtering system were found to form a nanocap-shaped nanostructure composed of a TiO2-Ag composite on each PS bead, in which the Ag nanoparticles were trapped partially or fully in the TiO2 matrix, depending on the TiO2 thickness. X-ray Photoelectron Spectroscopy (XPS) results showed the opposite shifts of binding energy for Ti 2p and Ag 3d, indicating the transfer of electrons from metallic Ag to TiO2 owing to the Ag-O-TiO2 composite formation. UV-Vis absorption spectra showed the blue shifts of the surface plasma resonance peaks, and the maximum absorption peak intensity was obtained for TiO2 at 30 nm. The surface-enhanced Raman scattering (SERS) peak intensity ?rst increased and then decreased when the TiO2 thickness changed. The observations of SERS, XPS, and UV-Vis absorption spectra were explained by the dependency of the charge-transfer process on TiO2 thickness, which was ascribed to the changing dielectric properties in the metal/semiconductor system.
关键词： electronic transfer,TiO2-Ag composites,surrounding dielectrics
更新于2025-09-23 15:22:29
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Enhanced Photocatalytic Hydrogen Evolution with TiO <sub/>2</sub> -TiN Nanoparticle Composites
摘要： Metal nitrides have potential in energy applications due to their physical and optical properties. Nanoparticle composites of titanium nitride (TiN) and titanium dioxide (TiO2) were investigated for their photocatalytic hydrogen (H2) activity via methanol reformation. Physical mixing of the nanoparticulate TiO2 and TiN was employed to prevent the oxy-nitride formation and particle aggregation observed in thermal preparations. This convenient combination of TiO2 and TiN demonstrated a substantial synergistic effect with enhanced activity (9.4 μmol/h TiO2-TiN vs 1.8 μmol/h TiO2) under combined UV/Vis light. Irradiation under only UV light resulted in a similar enhancement factor compared to using combined UV/Vis light, demonstrating that the enhanced activity of the composites occurs essentially for UV-driven photocatalysis. No activity/enhancement was observed with only visible light irradiation, however, minor enhancement was observed when switching between UV and UV/Vis irradiation, suggesting a contribution from the TiN plasmon. We propose that the plasmonic contribution is dependent on the band gap excitation of TiO2, which reduces the degree of band bending at the TiO2/TiN interface. This promotes the migration of hot electrons from TiN away from the TiO2/TiN interface to be used for H2 evolution.
关键词： TiO2-TiN Nanoparticle Composites,Plasmonics,Optical,Magnetic,and Hybrid Materials,Photocatalytic Hydrogen Evolution
更新于2025-09-23 15:22:29
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A poly (vinyl butyral)/graphene oxide composite with NIR light-induced shape memory effect and solid-state plasticity
摘要： A NIR light-induced shape memory composite with light-induced plasticity was prepared by incorporating graphene oxide (GO) into cross-linked poly (vinyl butyral) (PVB). The cross-linked reaction between PVB and aromatic diisocyanate not only endowed the composites with excellent shape memory properties, but also offered the performance of solid-state plasticity due to the formation of carbamate bonds. The photo-responsive performance was introduced to the system by doping GO, a conventional photothermal reagent, resulting in excellent NIR light-induced shape memory properties and light-induced plasticity. According to the stress relaxation tests, the solid-state plasticity of composites could be regulated by the cross-linked density, GO, catalyst dosage and temperature. Moreover, the composites can be repeatedly programmed to a new permanent shape via a light-induced plasticity process, which still exhibited excellent light-induced shape memory properties even after 5 cycles of reconfiguration. The results demonstrate the promising prospect of these composites as actuator elements for applications in self-deployment devices and soft robotic.
关键词： Smart materials,Functional composites,Shape memory polymers,Polymer-matrix composites (PMCs),Plastic deformation
更新于2025-09-23 15:21:21
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A novel reduced graphene oxide/epoxy sandwich structure composite film with thermo-, electro- and light-responsive shape memory effect
摘要： Development of multi-responsive shape recovery polymers and their composites is critical and has great potential. In this study, a novel reduced graphene oxide (RGO)/water-borne epoxy (WEP)/RGO sandwich structure composite film was fabricated and investigated. The results showed that the composite film exhibited excellent thermo-, electro- and light-responsive shape memory effect, which has potential applications for the sensors, switching devices, deployable structures, and medical apparatus.
关键词： Shape memory materials,Epoxy,RGO paper,Polymeric composites,Functional
更新于2025-09-23 15:21:21
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Photoemissive polymer composite based on new Y(III), Gd(III), and Tb(III) complexes with N-hydroxyphthalimide
摘要： In the present work, a green emitting composite with attractive photoluminescent properties was obtained through the embedding of the Tb 3+ complex with N-hydroxyphthalimide in a poly-(N-vinyl-pyrrolidone) matrix, which was further processed in thin or thick films. First, several complexes of Gd 3+ , Tb 3+ , and Y 3+ with N-hydroxyphthalimide with the general formula [M(NHF) 3 (DMF) 2 ] were prepared at a 1:3 metal/ligand ratio. The Tb 3+ complex presents specific emission peaks, with the most intense peak located at 543 nm, thus being selected for incorporation in the poly(N-vinyl-pyrrolidone) matrix. The prepared complexes and composites were investigated through elemental analysis, thermal analysis, FT-IR, P-XRD, and SEM. The photoluminescent properties were studied in detail. Remarkably, through the embedding in the poly(vinyl-pyrrolidone) matrix, the photoluminescent properties of the Tb 3+ complex are notably enhanced compared to the free complex.
关键词： Luminescent complexes,luminescent polymer composites,poly-(N-vinyl-pyrrolidone)
更新于2025-09-23 15:21:21
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3-Hydroxyflavone and N-phenylglycine in High Performance Photoinitiating Systems for 3D Printing and Photocomposites Synthesis
摘要： In this work, we propose to use 3-hydroxyflavone as a versatile high performance visible light photoinitiator (PIs) in combination with an amino acid (N-phenylglycine) for the free radical polymerization (FRP) of methacrylates in thick samples or composites upon visible light exposure (Light-Emitting Diode LED@405 nm or LED@477 nm). The high originality of this approach is the use of safer compounds in photoinitiating systems (flavone derivative/amino acid). 3-Hydroxyflavone can also be used in three-component systems with an iodonium salt and an amine for the cationic polymerization of epoxides upon exposure to near UV light LED@385 nm. Also interestingly, a charge transfer complex CTC between N-phenylglycine NPG and iodonium salt gives also remarkable initiating performance for free radical polymerization of methacrylates upon mild light irradiation conditions (LED@405 nm). High polymerization initiating abilities are found and high final reactive function conversions are obtained. The use of the new proposed initiating systems as materials for laser write or 3D printing experiments was also especially carried out with the formation of printed green fluorescent photopolymers. This green fluorescence obtained with naturally occurring 3-hydroxyflavone compound can be ascribed to the excited state intramolecular proton transfer ESIPT character. A full picture of the included photochemical mechanisms is given. Remarkably, 3-hydroxyflavone is also very efficient for photocomposites synthesis with glass fibers (thick samples with good depth of cure) using UV or LED@395 nm conveyor.
关键词： 3D printing,Cationic polymerization,Light-Emitting Diodes (LEDs),Free radical polymerization,photoinitiators,composites
更新于2025-09-23 15:21:21
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Preparation and Comparison of Hybridized WO3-V2O5 Nanocomposites Electrochemical Supercapacitor performance in KOH and H2SO4 Electrolyte
摘要： The rod shape WO3-V2O5 hybrid nanocomposites were prepared by microwave assisted wet chemical route. The electrochemical investigations of as-prepared composites were carried in two electrolytes such as KOH and H2SO4 for comparison. Their maximum capacitance was calculated as 44 F/g for WO3 and 173 F/g for WO3-V2O5 composites in KOH electrolyte and its efficiency is 100 % up to 5000 cycles and its capacitance retention is 126% in KOH electrolyte. In H2SO4 electrolyte, the specific capacitance of WO3 was recorded as 246 F/g and WO3-V2O5 showed poor performance such as less than 12 F/g.
关键词： Energy storage and conversion,supercapacitor,hybrid composites,WO3-V2O5
更新于2025-09-23 15:21:21
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Study on properties of barium titanate/polyethersulfone dielectric composites prepared by physical dispersion method
摘要： Composite materials applied to capacitors with high dielectric constant, low dielectric loss and outstanding thermal stability are concerned widely in the field of dielectrics. So committed to the development of dielectric materials with excellent performance is the key factor. In this work, the barium titanate/polyether sulfone (BaTiO3/PES) composite films were prepared by a physical dispersion technology, which utilized a ball milling machine by high-speed circulation, scattered the PES solution contained BaTiO3 in deionized water with the aid of a surfactant. Then, the BaTiO3/PES composite films were obtained through a series of operations, containing reclaimed organic solvent, washed with deionized water, filtered, dried and hot pressed. The morphology of the BaTiO3/PES emulsion was investigated by TEM and SEM. The results showed that the BaTiO3 particles were covered in the PES resin matrix homogeneously. For 50?wt% BaTiO3 reinforced PES composite film. The dielectric constant increased by ~ 227% compared with pure PES resin (4.1 at 1?kHz) and the dielectric loss maintained around 10?2 magnitude, which performed better dielectric properties. The tensile strength of 10?wt% BaTiO3/PES composite films (72?MPa) reached the highest value in comparison with those of pure PES (58?MPa) due to the strengthened interaction between particles and matrix. Further increase of BaTiO3 content, the tensile strength and elongation at break decreased slightly but remained an excellent flexibility from the PES matrix. The temperature at weight loss 5% (T5%) of composite film with 40?wt% of BaTiO3 content reached up to 503?°C in N2 atmosphere. All the BaTiO3/PES composite films performed the concentrated glass transition temperature (Tg) around 229?°C. In sum, excellent thermal stability and dielectric properties would make the BaTiO3/PES composite films become the fine potential candidates for dielectric composites in the capacitors.
关键词： barium titanate,dielectric composites,polyethersulfone,physical dispersion method
更新于2025-09-23 15:21:21
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Reinforcement of a laser-textured 316L steel with CuCoBe-diamond composites through laser sintering
摘要： The aim of this work was the production and the characterization of a laser textured 316L stainless steel reinforced with CuCoBe-diamond composites by laser sintering. The composites were obtained from CuCoBe and synthetic diamond with different particle sizes by mechanical alloying. The influence of the reinforcement on the physical, chemical and surface properties was analyzed. The results showed that the textured pattern consisted of square pyramids with a machined area of approximately 80%. The interfaces between the steel and the reinforcement after sintering are well defined and sharp. A good adherence of the diamond particles to the CuCoBe matrix was achieved. The laser sintering process did not induce any phase transformations or oxidation of the reinforcement. The steel reinforced with the biggest diamond particles exhibited substantially better surface performance than the untextured material.
关键词： composites,sintering,diamond,steel,Mechanical,316L,CuCoBe,alloying,texturing,laser
更新于2025-09-23 15:21:01