- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Facile Construction of Defect-rich Rhenium Disulfide/Graphite Carbon Nitride Heterojunction via Electrostatic Assembly for fast Charge Separation and Photoactivity Enhancement
摘要： Graphite carbon nitride (CN) is one of the most researched visible light photocatalysts, but it still cannot be used practically because of its low photoactivity resulting mainly from rapid photogenerated charge recombination. To accelerate charge separation, CN was herein electrostatically assembled with ReS2, a two-dimensional semiconductor to construct heterojunction for the first time. The electrostatic and coordination interactions between CN and defect-rich ReS2 make them close contact to form heterojunctions. The ReS2/CN heterojunction exhibits higher photocatalytic performance in pollutant degradation owing to faster generation of reactive oxygen species than CN, as well as increased visible and near-infrared light absorption because of strong photoabsorption of defect-rich ReS2. The accelerated reactive oxygen species generation for the heterojunction arises from accelerated charge separation, especially fast transfer of holes from CN to ReS2 in assistance of interfacial electric field and great valance-band edge difference. This work provides a novel CN-based heterojunction for photoactivity improvement and illustrates significance of electrostatic attraction in fabricating heterojunctions.
关键词： electrostatic interaction,photocatalytic,rhenium disulfide,graphite carbon nitride,charge separation
更新于2025-11-21 11:03:13
-
Preparation of Ag-AgVO3/g-C3N4 composite photo-catalyst and degradation characteristics of antibiotics
摘要： The degradation of tetracycline by silver vanadate (AgVO3), graphite-like carbon nitride (g-C3N4) and their composites was studied by visible light photocatalysis. Their structures and morphologies were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Their degradation intermediates were analyzed by GC-MS. Nanorod silver vanadate was synthesized by hydrothermal method. The results show that the gap between nanorods is reduced by adding spinning carbon nitride, and the photocatalytic performance of the composite is stronger than that of single material. The reaction rate constants of Ag-AgVO3/g-C3N4 composites were 0.0298 min-1, 2.4 and 2.0 times that of g-C3N4 (K=0.0125 min-1) and AgVO3 (K=0.0152 min-1), respectively. At 120 minutes, the degradation rate of the composites reached 83.6%. The degradation of tetracycline was confirmed by GC-MS, and a possible degradation process was proposed.
关键词： Photo-catalysis,Carbon nitride,Antibiotics,Visible light,Silver vanadate
更新于2025-11-21 10:59:37
-
Aminoboronic acid-functionalized graphitic carbon nitride quantum dots for the photoluminescence multi-chemical sensing probe
摘要： This paper reports a highly sensitive photoluminescence glucose sensor based on aminoboronic acid-functionalized carbon nitride quantum dots (g-CNQDs/3APBA) fabricated using melamine and 3-aminophenylboronic acid via a facile two-step synthesis process. By introducing the covalent bonds between g-CNQDs and boronic acid groups, it can be effectively used as “on-off-on” based multi-chemical sensor. The g-CNQDs/3APBA exhibited quantum yields (QYs) as high as 78.5%, which is the highest QYs among fluorescence sensors based on g-CNQDs reported thus far. The material showed a wide linear range of 0 – 10 mM and a detection limit as low as 42 nM with excellent selectivity. In addition, it exhibited comparable performance compared to those of a commercial glucometer in a real blood test. Owing to the excellent bio-imaging properties and low cytotoxicity, g-CNQDs/3APBA is a promising candidate as a sensing material for biomedical and clinical applications.
关键词： quantum dots,glucose sensor,multi-chemical sensor,fluorescence,Graphitic carbon nitride,3-aminophenylboronic acid
更新于2025-11-20 15:33:11
-
Laser-induced synthesis and photocatalytic properties of hybrid organic–inorganic composite layers
摘要： A laser-based method was developed for the synthesis and simultaneous deposition of multicomponent hybrid thin layers consisting of nanoentities, graphene oxide (GO) platelets, transition metal oxide nanoparticles, urea, and graphitic carbon nitride (g-C3N4) for environmental applications. The photocatalytic properties of the layers were tested through the degradation of methyl orange organic dye probing molecule. It was further demonstrated that the synthesized hybrid compounds are suitable for the photodegradation of chloramphenicol, a widely used broad-spectrum antibiotic, active against Gram-positive and Gram-negative bacteria. However, released in aquatic media represents a serious environmental hazard, especially owing to the formation of antibiotic-resistant bacteria. The obtained results revealed that organic, urea molecules can become an alternative to noble metals co-catalysts, promoting the separation and transfer of photoinduced charge carriers in catalytic composite systems. Laser radiation induces the reduction of GO platelets and the formation of graphene-like material. During the same synthesis process, g-C3N4 was produced, by laser pyrolysis of urea molecules, without any additional heat treatment. The layers exhibit high photocatalytic activity, being a promising material for photodegradation of organic pollutants in wastewater.
关键词： transition metal oxide nanoparticles,urea,photocatalytic properties,hybrid organic–inorganic composite layers,graphene oxide,graphitic carbon nitride,methyl orange,laser-based synthesis,chloramphenicol
更新于2025-11-14 17:04:02
-
Sulfur doped carbon nitride quantum dots with efficient fluorescent property and their application for bioimaging
摘要： Heteroatom doping can drastically alter electronic characteristics of carbon nitride quantum dots, thus resulting in unusual properties and related applications. Herein, we used sulfur as the doping element and investigated the influence of doping on the electronic distribution of carbon nitride and the corresponding fluorescent property. A simple synthetic strategy was applied to prepare sulfur-doped carbon nitride (S-g-C3N4) quantum dots through ultrasonic treatment of bulk S-g-C3N4. Characterization results demonstrated that the prepared S-g-C3N4 quantum dots with an average size of 2.0 nm were successfully prepared. Fluorescent properties indicated that S-g-C3N4 quantum dots have an emission peak at 460 nm and cover the emission spectra region up to 550 nm. Furthermore, the fluorescent intensity is greatly increased due to the sonication of bulk S-g-C3N4 into quantum dots. As a result, S-g-C3N4 quantum dots not only show a blue cell imaging, but have a bright green color. Therefore, S-g-C3N4 quantum dot is a promising candidate for bioimaging benefiting from the efficient fluorescent property, good biocompatibility, and low toxicity.
关键词： Doped carbon nitride,Fluorescent property,In vitro cytotoxicity,Quantum dots,Bioimaging
更新于2025-11-14 17:04:02
-
Electrochemiluminescence sensing platform for ultrasensitive DNA analysis based on resonance energy transfer between graphitic carbon nitride quantum dots and gold nanoparticles
摘要： Electrogenerated chemiluminescence (ECL) of semiconductor quantum dots (QDs) is considered as a powerful technique in the fabrication of biosensor, however, the inherent toxicity of the heavy metal ion containing in QDs limits their further applications. Thus, searching for environment-friendly luminescent nanomaterials with high electrochemiluminescence (ECL) e?ciency is an urgent goal. In this work, a solid-state method under low temperature was adopted to prepare graphitic carbon nitride quantum dots (g-CNQDs). By using coreactant K2S2O8, a strong cathodic ECL signal of g-CNQDs could be observed in phosphate bu?er. A novel ECL resonance energy transfer procedure was constructed between g-CNQDs (emitter) and gold nanoparticles (acceptor). A signal probe was formed by connecting gold nanoparticles at the hairpin DNA (Hai-DNA) terminal. When the signal probe was anchored on g-CNQDs, ECL resonance energy transfer occurred due to the ECL quenching of gold nanoparticles to g-CNQDs. This phenomenon decreased the ECL signal. In the presence of target DNA (T-DNA), the looped structure of Hai-DNA could be destroyed by T-DNA, and gold nanoparticles were separated from g-CNQDs. Accordingly, the ECL resonance energy transfer procedure was hindered, and the ECL signal was recovered again. The ECL intensities exhibited linear correlation with the logarithm of T-DNA concentration from 0.02 fM to 0.1 pM, and the limit of detection was 0.01 fM (3σ). With the developed ECL resonance energy transfer system, good selectivity and high sensitivity were achieved in T-DNA detection.
关键词： Graphitic carbon nitride quantum dots,Electrochemiluminescence,DNA,Resonance energy transfer,Biosensor
更新于2025-11-14 17:04:02
-
In-Situ Synthesis of Nb2O5/g-C3N4 Heterostructures as Highly Efficient Photocatalysts for Molecular H2 Evolution under Solar Illumination
摘要： This work focuses on the synthesis of heterostructures with compatible band positions and a favourable surface area for the efficient photocatalytic production of molecular hydrogen (H2). In particular, 3‐dimensional Nb2O5/g‐C3N4 heterostructures with suitable band positions and high surface area have been synthesized employing a hydrothermal method. The combination of a Nb2O5 with a low charge carrier recombination rate and a g‐C3N4 exhibiting high visible light absorption resulted in remarkable photocatalytic activity under simulated solar irradiation in the presence of various hole scavengers (triethanolamine (TEOA) and methanol). The following aspects of the novel material have been studied systematically: the influence of different molar ratios of Nb2O5 to g‐C3N4 on the heterostructure properties, the role of the employed hole scavengers, and the impact of the co‐catalyst and the charge carrier densities affecting the band alignment. The separation/transfer efficiency of the photogenerated electron‐hole pairs is found to increase significantly as compared to that of pure Nb2O5 and g‐C3N4, respectively, with the highest molecular H2 production of 110 mmol/g·h being obtained for 10 wt % of g‐C3N4 over Nb2O5 as compared with that of g‐C3N4 (33.46 mmol/g·h) and Nb2O5 (41.20 mmol/g·h). This enhanced photocatalytic activity is attributed to a sufficient interfacial interaction thus favouring the fast photogeneration of electron‐hole pairs at the Nb2O5/g‐C3N4 interface through a direct Z‐scheme.
关键词： Z‐Scheme,H2 evolution,hydrothermal synthesis,graphitic carbon nitride,photocatalysis,heterostructures,Niobium(V) oxide
更新于2025-11-14 17:03:37
-
Acetylene black quantum dots as a bridge for few-layer g-C3N4/MoS2 nanosheet architecture: 0D–2D heterojunction as an efficient visible-light-driven photocatalyst
摘要： Great progress has been made based on photocatalytic theory research in the past few years. There is, however, still a long way to go to popularize the application of photocatalytic materials. Here, we introduce a simple synthetic 0D–2D (D: dimensional) heterogeneous material with more efficient photocatalytic degradation. We construct acetylene black (AB) as a bridge to connect a graphitic carbon nitride (g-C3N4) nano-layer and two-dimensional MoS2 sandwich structure based on a simple hydrothermal synthesis and ultrasonic chemical loading. Loading 1% AB onto 2D g-C3N4/(x%)MoS2 not only accelerates the transfer of charge, but also reduces electron–hole recombination, which increases the photocatalytic efficiency per unit time. Studies have shown that the degradation rate of the ternary g-C3N4/AB/3.1%MoS2 catalytic materials can reach 94.29%, which is obviously higher than that of the pure g-C3N4 (80%) or MoS2 (51.74%) in degradation of methyl blue within 130 min. In this work, the ternary heterogeneous catalyst realizes the complementary characteristics between materials, broadens the photocatalytic properties and accelerates the degradation rate of pollutants, and provides a feasible solution to environmental friendliness.
关键词： Graphitic carbon nitride,Ternary photocatalyst,Photocatalytic degradation,QDs/g-C3N4/MoS2
更新于2025-11-14 15:32:45
-
Efficient visible light driven degradation of sulfamethazine and tetracycline by salicylic acid modified polymeric carbon nitride via charge transfer
摘要： Photocatalysis has been widely studied as a promising technique for removal of organic pollutants in wastewater. A modified carbon nitride has been designed for this purpose. In this study, a facile method to synthesize distorted carbon nitride by simply copolymerizing urea and salicylic acid (SA) has been explored. The incorporation of SA induced the structure change from planar structure to distorted curls structure. Compared to pristine CN, the CN-SA shows wide light absorption, which is attributed to the n → π* transition at the nitrogen atoms with lone pair electrons of heptazine units. The photoelectrode of CN-SA exhibited higher photocurrent and lower charge resistance than that of pristine CN electrode, indicating that the photogenerated charge carriers of CN-SA are more efficiently separated. As a result, the optimal CN-SA shows 2-fold enhancement in degradation of tetracycline (TC) as compared to pristine CN. Furthermore, we found that the degradation rate of sulfamethazine (SMZ) was 0.0823 min?1 using the CN-SA photocatalyst, which is three times higher than that of pristine CN (0.0293 min?1). In addition, the CN-SA shows good stability without structural change or loss of photocatalytic performance after four cycles. According to the radical species trapping experiments and electron spin resonance analyses, ?O2? and h+ were the main active species involved in the degradation of organic pollutants. The developed strategy provides a novel approach to design the tunable band structure of organic semiconductor materials for various applications.
关键词： Salicylic acid,Photocatalysis degradation,Carbon nitride,Charge separation,Antibiotics
更新于2025-11-14 14:48:53
-
Visible light photocatalytic mineralization of bisphenol A by carbon and oxygen dual-doped graphitic carbon nitride
摘要： A facile thermal polymerization was applied to synthesize carbon and oxygen dual-doped graphitic carbon nitride (MACN) with controllable electronic band structure using malonic acid and urea as precursors. The C and O atoms substituted the sp2 N atom in graphitic carbon nitride (CN). The 1MACN (1 represented that the weight ratio of malonic acid to urea is 1% during the synthesis) with optimal band structure could decompose 15 ppm bisphenol A (BPA) within 150 min, and the mineralization rate reached to 52%. The superior photocatalytic performance of 1MACN was mainly ascribed to electronic band structure together with optical properties. On the one hand, the formation of delocalized big p bonds favored the electrons transfer after the introducing of carbon atoms. On the other hand, a positive charge density existed on the C atoms because of high electronegativity of contiguous O (3.44) that substituted N compared with C (2.55), which could attribute to high activity of MACN catalyst. The study will contribute to the further improvement of visible-light photocatalytic BPA degradation and mineralization.
关键词： BPA mineralization,Carbon-oxygen dual-doping,Visible-light photocatalytic,Graphitic carbon nitride
更新于2025-09-23 15:23:52