Nanomaterials
·
2016
·Vol. 6
·期 8
·152
·
IF 2.69
Zongjie Li,Weimin Kang,Huihui Zhao,Min Hu,Na Wei,Jiuan Qiu,Bowen Cheng
A novel polyvinylidene fluoride (PVDF) tree-like nanofiber membrane (PVDF-TLNM) was fabricated by adding tetrabutylammonium chloride (TBAC) into a PVDF spinning solution via one-step electrospinning. The structure of the prepared membranes was characterized by field emission scanning electron microscopy (FE-SEM), Fourier transform infrared spectroscopy (FT-IR) and pore size analysis, and the hydrophilic property and microfiltration performance were also evaluated. The results showed that the tree-like nanofiber was composed of trunk fibers and branch fibers with diameters of 100–500 nm and 5–100 nm, respectively. The pore size of PVDF-TLNM (0.36 μm) was smaller than that of a common nanofiber membrane (3.52 μm), and the hydrophilic properties of the membranes were improved significantly. The PVDF-TLNM with a thickness of 30 ± 2 μm showed a satisfactory retention ratio of 99.9% against 0.3 μm polystyrene (PS) particles and a high pure water flux of 2.88 × 104L·m−2·h−1under the pressure of 25 psi. This study highlights the potential benefits of this novel PVDF tree-like nanofiber membrane in the membrane field, which can achieve high flux rates at low pressure.Keywords:electrospinning;polyvinylidene fluoride;tree-like;nanofibers;microfiltration
研究领域:
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MATERIALS & DESIGN
·
2015
·
IF 3.501
Zongjie Li,Yongzheng Xu,Lanlan Fan,Weimin Kang,Bowen Cheng
A novel polyvinylidene fluoride (PVDF) tree-like nanofiber was controllably fabricated via one-step electrospinning by adding certain amount of salt into PVDF solution. A possible mechanism for the formation of the tree-like nanofibers was proposed by analyzing high speed camera photos of the spin jet and the result showed that the formation of tree-like nanofibers was due to the splitting of jets. The effects of salt type, salt content and processing parameter on the content of tree-like branches were investigated. The electrospun nanofibers were characterized by field emission scanning electron microscopy (FE-SEM), energy disperse spectroscopy (EDS), X-ray diffraction (XRD), pore size meter and mechanical properties measurement. It was found that the PVDF/TBAC tree-like nanofibers with improved crystallinity and mechanical strength . The decreased average pore size caused by the tree-like structure and the resistance to organic solvent , can make it as a potential candidate for membrane separation .
研究领域:
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 14
·8220-8229
·
IF 3.108
Zongjie Li,Weimin Kang,Na Wei,Jiuan Qiu,Cheng Sun,Bowen Cheng
A novel polyvinylidene fluoride/tetrabutylammonium chloride (PVDF/TBAC) tree-like nanofiber mat loaded with manganese dioxide (MnO2) as a highly efficient lead adsorbent was successfully fabricated. The adsorbent was prepared by in situ polymerization of pyrrole monomer on the surface of the PVDF/TBAC tree-like nanofiber mat, and subsequently reacted with KMnO4 solution to deposit MnO2. The morphology and structure of the as-prepared adsorbent were measured by field emission scanning electron microscopy (FE-SEM) and the tree-like structures can be clearly seen from the FE-SEM images. Fourier transform infrared spectroscopy (FT-IR) results confirmed the presence of PPy and MnO2 layers on the surface of PVDF/TBAC tree-like nanofibers. Thermo-gravimetric analysis (TGA) results exhibited that MnO2 accounted for about 43.27% in the PVDF/TBAC–polypyrrole–MnO2 (PVDF/TBAC–PPy–MnO2) nanofiber mat. The kinetics of Pb2+ adsorption was found to follow a pseudo-second-order rate model. The adsorption isotherms were fitted best with the Langmuir isotherm model. The thermodynamic analysis confirmed that the adsorption process was endothermic and spontaneous. The regeneration experiments showed that the obtained tree-like PVDF/TBAC–PPy–MnO2 nanofiber mat also exhibited high recyclable removal efficiency. XPS analysis showed that ion exchange was the main mechanism for Pb2+ adsorption.
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
RSC Advances
·
2016
·Vol. 6
·期 94
·91243-91249
·
IF 3.289
Zongjie Li,Weimin Kang,Huihui Zhao,Min Hu,Jingge Ju,Nanping Deng,Bowen Cheng
A novel polyvinylidene fluoride (PVDF) tree-like nanofiber web was successfully fabricated via one-step electrospinning. The effect of the tree-like structure on the pore size distribution and specific surface area were measured, and the filtration properties of the tree-like nanofiber webs with different basis weights were investigated. The results showed that the tree-like structure significantly decreased the pore size and narrowed the range of pore size distribution, and dramatically enhanced the specific surface area. In comparison with common PVDF nanofiber webs, the tree-like nanofiber webs exhibited excellent filtration performance. The filtration efficiency of the tree-like nanofiber webs with the basis weight of 1 g m−2 to 0.26 μm NaCl particles was 99.999% and the pressure drop was only 124.2 Pa which was comparable to ultra low penetration air filters (ULPA). The tree-like nanofiber webs will be widely used in the field of high efficiency and precision filter materials and medical protective materials.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2023
·
IF 8.6
Zongjie Li,Shuye Wang,Xinhui Wang,Xiaobin Sun,Weimin Kang,Yong Liu
The development of membrane with strong sunlight absorption and high energy efficiency is the key to improve the water production efficiency in photothermal membrane distillation (PMD). In this paper, a hierarchical Cu-based metal–organic framework-functionalized polyvinylidene fluoride (PVDF) tree-like nanofiber membrane (Cu-CAT@TLNM-TLNMs) was developed for high-efficient PMD. The Cu-CAT@TLNM-TLNM was prepared by in-situ growth of Cu-CAT on the surface of PVDF tree-like nanofiber membrane (TLNM) as photothermal layer and PVDF TLNM as support layer, which exhibited excellent photothermal conversion performance, high energy utilization and high permeate flux. The PVDF TLNM with high specific surface area provided more active sites for the growth of Cu-CAT, thus forming a uniform Cu-CAT nanoarray. The spinous structure of the Cu-CAT photothermal layer can increase the length of the light-matter interaction and improve light absorption. In addition, the tree-like structure of the support layer with high porosity and small pore size can improve the permeate flux and long-term stability. Under the illumination of 1 kW·m −2 , the surface temperature of the Cu-CAT@TLNM-TLNMs reached about 80 °C within 50 s, with a permeate flux of 1.37 kg·m −2 ·h −1 , a salt rejection of >99.99 %, and a photothermal conversion efficiency of 76 %. More importantly, the permeate flux of the Cu-CAT@TLNM-TLNMs was still stable at 0.79 kg·m −2 ·h −1 with a salt rejection of >99.99 % after 84 h of continuous operation. This photothermal nanofiber composite membrane can be applied to solve the problem of freshwater shortage in areas where freshwater and fuel resources are scarce and solar energy is abundant.
研究领域:
材料科学
·
环境工程
·
纳米技术
·
水处理
✓ 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）