RSC Advances
·
2020
·Vol. 10
·期 33
·19669-19685
·
IF 3.119
Shuting Zhang,Guoqiang Li,Liyuan Duan,Hongyu Wang,Yongle Zhao,Yongfa Zhang
Graphitic carbon nitride (g-C3N4) was prepared by a simple thermal polymerization method in this work. The effects of precursor type, thermal polymerization temperature, constant temperature time and atmosphere on the crystal structure, morphology, elemental composition, valence distribution, light absorption properties and photocatalytic activity of the prepared photocatalytic materials were investigated. Taking rhodamine B (RhB) as the target degradant, the blue light catalytic activity of the photocatalytic material was studied in detail. The experimental results showed that the final pyrolysis temperature and constant temperature time are positively related to the adsorption characteristics and photocatalytic ability of the prepared materials. In addition, the adsorption capacity and photocatalytic activity of the products obtained in Ar and H2 atmospheres are better than those produced in CO and CH4, which can be attributed to the combined effect of large specific surface area and structural defects of the materials. The sample's large specific surface area, wide band gap, and excellent photogenerated carrier separation and transfer capabilities make the adsorption performance and photocatalytic performance of the products obtained with ammonium thiocyanate and thiourea as precursors better than those prepared from melamine and dicyandiamide. g-C3N4 prepared by using ammonium thiocyanate as precursor at 550 °C for 5 h under a hydrogen atmosphere showed the best catalytic activity for the degradation of RhB under blue light. It was demonstrated that g-C3N4 prepared exhibited good stability and reusability after four repeat experiments. The active components that play major roles in the degradation of RhB described herein were holes and superoxide radicals, which was inferred by free radical trapping experiments. This work provides a theoretical basis for the idea of converting the mixed salts of desulfurization waste liquid containing ammonium thiocyanate into an excellent photocatalyst g-C3N4 with visible light response.
研究领域:
材料科学
·
环境科学
·
光催化技术
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产品关联
DOI
PubMed
高影响因子
SENSORS
·
2025
·Vol. 25
·期 10
·3228
·
IF 3.5
Lihua Zhang,Jiang Li,Juan Wang,Xu Yan,Jinping Song,Feng Feng
HighlightsWhat is the main findings?ATG-functionalized AuNPs were prepared as a colorimetric chemosensor with ultra-sensitivity for the simultaneous detection of MOX/CIP and Cr(III).What are the implications of the main findings?ATG-AuNPs sensor color transitions from wine-red to gray-blue indicated successful detection.The detection limits for MOX/CIP and Cr(III) are 1.57 µM, 1.30 µM, and 57.1 nM, respectively.The presented method was used to detect multiple analytes in lake and tap water samples.Water pollution by antibiotics and heavy metals threatens the ecological environment and human health globally, yet there is no rapid method to detect multiple antibiotics and metal ions simultaneously. A simple, fast, and ultra-sensitive colorimetric chemosensor for the simultaneous detection of moxifloxacin (MOX), ciprofloxacin (CIP), and Cr(III) based on the aggregation of ammonium thioglycolate (ATG)-functionalized gold nanoparticles (ATG-AuNPs) was developed. Following the addition of MOX, CIP, and Cr(III), a color change in the solution was observed from wine-red to blue-grey. The UV–Vis signal of the ATG-AuNPs system blended with MOX, CIP, and Cr(III) in the range of 0~200 µM, 0~100 µM, and 0~5 µM was assessed and measured with detection limits (LODs) of 1.57 µM, 1.30 µM, and 57.1 nM calculated by 3σ/S, respectively. Therefore, this system has the potential to act as an effective colorimetric chemosensor for simultaneously detecting MOX, CIP, and Cr(III) in complex environmental systems.
研究领域:
环境科学
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
WATER AIR AND SOIL POLLUTION
·
2025
·Vol. 236
·期 10
·1-16
·
IF 3
Li Jiatong,Song Lei,Zhang Hao,Wang Runnan,Zhu Bo,Lou Dawei
In this study, a novel composite flocculant was prepared using sodium silicate, aluminum sulfate, and thiosemicarbazone as experimental raw materials. The successful synthesis of the composite flocculant was verified through Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy-energy-dispersive X-ray spectroscopy (SEM–EDS), and X-ray photoelectron spectroscopy (XPS). The influence of pH levels in water samples, initial heavy metal ion concentrations, and flocculant dosage on copper ions removal efficiency was systematically studied. The experimental results demonstrate that the removal of Cu 2+ under optimum conditions reached 96.88%. The Langmuir isotherm model predicts a maximum Cu 2+ adsorption capacity reaching 1568.6 mg/g. The adsorption kinetics indicate that the removal of heavy metal ions by this flocculant is dominated by chemisorption. When combined with zeta potential analysis of the flocculation mechanism, charge neutralization emerged as the controlling factor during flocculation, and additional mechanisms such as chelating and precipitation, adsorption and bridging, and sweep flocculation are also involved.
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产品关联
DOI
高影响因子
BRAZILIAN JOURNAL OF CHEMICAL ENGINEERING
·
2024
·
IF 1.5
Li Yufang,Chen Yunlong,Zi Futing,Hu Xianzhi
Eco-friendly gold extraction from printed circuit boards (PCBs) is highly attractive due to the increasing demand for gold in various fields. The conventional Cu 2+ -NH 3 - S 2 O 3 2− method for PCBs involves polluting NH3 gas and requires additional copper. This study explored a new eco-friendly alternative using ethylenediamine (en) and thiosulfate to extract gold from CPU (the PCB material used in this study). The results showed that 81% of gold in CPUs could be successfully leached out after 48 h, using 10 mM ethylenediamine and 0.2 M thiosulfate. Various analyses, including SEM, ICP, XPS, were conducted to further investigate the process. It was found that the metal in CPU was Au(0) → Ni(II) → Cu(0) from the outside to the inside, and possible gold leaching mechanism was related to the oxidation of Cu(en) 2 2+ produced from CPU’s defective position and the presence of S 2 O 3 2− . As for Au(S 2 O 3 ) 2 3− recovery, different from our previous study, it is necessary to add a small amount of ethylenediamine (en) except for carbon and thiosemicarbazone (TSC); consequently, a gold adsorption efficiency of 99% was achieved. In summary, the leaching method proposed in this work solved the problem of NH 3 pollution of traditional one and achieves green, efficient, and selective gold adsorption from CPU leaching solution through a simple method, which is hopeful to replace the traditional unfriendly Cu-NH 3 - S 2 O 3 2− .
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）