CARBON
·
2021
·
IF 9.594
Gaoxu Han,Jianbo Jia,Quanrun Liu,Guangxu Huang,Baolin Xing,Chuanxiang Zhang,Yijun Cao
A series of coal-based hierarchical porous carbons with adjustable pores were successfully prepared with the assistance of the soluble salt Zinc chloride (ZnCl 2 ). During the carbonization process , ZnCl 2 , with a low melting point (238 °C), “in situ occupied” and “occupied” within the coal solids to generate interconnected pores, which acted as a template. Simultaneously, the activation of ZnCl 2 reduced the oxygen content of products and further improves their electrical conductivity . Optimization of the mass of the salt and the carbonization temperature resulted in targeted product with a suitable specific surface area (1581 m 2 g −1 ) and unique pores (V meso /V total = 45%), which exhibited a high specific capacitance (470.7 F g −1 at 0.5 A g −1 ) in 6 M KOH electrolyte. The symmetrical supercapacitor of targeted product has favorable rate performance (256.7 F g −1 at 0.5 A g −1 , 84.8% capacity retention at 30 A g −1 ) and excellent cycling performance (after 10000 cycles, the specific capacitance increases to 115% of the initial capacity at 10 A g −1 ). In the EMIMBF 4 electrolyte system, the energy density is 95.31 Wh kg −1 at 213.13 W kg −1 . Therefore, this work provides an effective method to improve the green and efficient use of coal.
研究领域:
材料科学
·
能源技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ENVIRONMENTAL MANAGEMENT
·
2022
·
IF 8.91
Xuankun Wei,Feng Xie,Chunling Dong,Pengju Wang,Jiyun Xu,Feng Yan,Zuotai Zhang
Hazardous waste incineration fly ash (HFA) is considered a hazardous waste owing to the high associated concentrations of heavy metals and soluble salts . Hence, cost effective methods are urgently needed to properly dispose HFA. In this study, geopolymers were prepared by alkali-activation technology to stabilize and solidify heavy metals in HFA. In addition, the effects of three different aluminosilicates (metakaolin, fly ash, and glass powder) on the heavy metal immobilization efficiency were investigated. Because the soluble salt content of HFA is too high for their direct placement in flexible landfill sites and water washing can lead to heavy metal leaching, water-washing experiments were conducted after alkali-activation treatment to remove soluble salts. The results suggest that the concentrations of heavy metals leached from geopolymers can satisfy the Chinese Standard limits (GB18598-2019) when the addition of aluminosilicates exceeds 20 wt%. More than 77% of Cl − and >64% of SO 4 2− in geopolymers could be removed via water-washing treatment. The Zn leaching concentration was maintained below approximately 0.52 ppm. After alkali-activation treatment, the water-washing process could efficiently remove soluble salts while inhibiting heavy metal leaching. Sodium-aluminosilicate-hydrate (N-A-S-H) gel, a product of the geopolymerization process in this study, was demonstrated to act as a protective shell that inhibited heavy metal leaching. Hence, HFA-based geopolymers are considered suitable for disposal in flexible landfills.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2022
·
IF 11.357
Danting Shi,Tengjing Gong,Weihua Qing,Xianhui Li,Senlin Shao
Scaling-induced wettinggreatly limits the application of membrane distillation (MD) for the desalination of high-salinity feed. Although highly soluble salts (e.g., NaCl) have high concentrations in this water, their scaling-induced wetting remains overlooked. To unravel the elusive wetting behaviors of highly soluble salts, in this study, we systematically investigated the scaling formation and wetting progress by in situ observation with optical coherence tomography (OCT). Through examining the influence of salt type and vapor flux on the wetting behavior, we revealed that highly soluble salt-induced wetting, especially under high vapor flux, shared several unique features: (1) occurring before the bulk feed reached saturation, (2) no scale layer formation observed, and (3) synchronized wetting progress on the millimeter scale. We demonstrated that a moving scale layer caused these interesting phenomena. The initial high vapor flux induced high concentration and temperature polarizations, which led to crystallization at the gas–liquid interface and the formation of an initial scale layer. On the one hand, this scale layer bridged the water into the hydrophobic pores; on the other hand, it blocked the membrane pores and reduced the vapor flux. In this way, the decreased vapor flux mitigated the concentration/temperature polarizations, and consequently led to the dissolution of the feed-facing side of the scale layer. This dissolution prevented the membrane pores from being completely blocked, facilitating the transportation and crystallization of salts at the distillate-facing side of the scale layer (i.e., the gas–liquid interface), thus the proceeding of the wetting layer.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Yidong Zhang,Rong Shao,Wei Xu,Jianfei Ding,Yuan Wang,Xiuhua Yan,Wenyan Shi,Min Wang
Hierarchical porous materials receive extensive attention due to their excellent electrode kinetic performance. Herein, a facile strategy is presented to fabricate hierarchical porous supercapacitor materials using NaCl-assisted MOFs gel as a structure-directing template. By controlling the additive amount of NaCl, hierarchical porous carbon-encapsulated Fe 3 C with tailored pore size distribution has been obtained with a high specific capacity of 184.1 mAh g −1 (602.3F g −1 ) at a current density of 1 A g −1 . The analysis of kinetics and impedance indicates that the tailored porosity can provide broad ion diffusion pathway and low charge-transfer resistance. Meanwhile, seawater was used instead of NaCl for preparing hierarchical porous carbon with good capacitive performance. When evaluated their practical applications, the assembled all-solid-state hybrid supercapacitor delivers a high energy density of 30.6 W h kg −1 at a power density of 600 W kg −1 , and even maintains an energy density of 15.5 W h kg −1 at a power density of 12000 W kg −1 with 86.5% capacity retention after 10,000 cycles. This work is anticipated to open up a new route of using MOFs gel and water-soluble salts for designing hierarchical porous electrode s materials, which pave the way for advanced utilization of MOFs gel and seawater.
研究领域:
材料科学
·
电化学
·
纳米能源
·
功能材料
·
储能技术
✓ 已验证
DOI
高影响因子
Nano Energy
·
2019
·
IF 15.548
Lianmeng Cui,Limin Zhou,Kai Zhang,Fangyu Xiong,Shuangshuang Tan,Maosheng Li,Qinyou An,Yong-Mook Kang,Liqiang Mai
Benefiting from high volumetric energy density and generally dendrite-free growth of Mg metal, rechargeable magnesium batteries (MBs) become a promising next-generation energy storage system . Organic electrode materials, with characteristic of sustainable resource and flexible structure, have been widely studied in alkali metal ion batteries , but are rarely reported in MBs. Herein, we demonstrate that 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA) serves as a cathode material for MBs in non-aqueous system, which realizes a fast diffusion kinetics and remarkable Mg-storage performance through a salt-dissolution inhibition approach for the electrolyte. The PTCDA exhibits a reversible capacity of 126 mAh g −1 (at 200 mA g −1 ), excellent rate performance, and good cycling stability (100 mAh g −1 even after 150 cycles). Furthermore, the evolution mechanism of the PTCDA electrode based on the transformation between carbonyl groups (C O) and enolate groups (C–O) is revealed by ex-situ phase characterization and functional group analysis. Besides, the dissolution inhibition of the PTCDA could also be realized through the incorporation of other soluble salt (KCl or NaCl) into all phenyl complex (APC) electrolyte, resulting in an enhanced cycling capacity. Considering the designable configuration of the organic materials, this work would pave way for their utilization on multi-valent ion batteries and provide efficient strategy to realize high voltage and satisfied cycle life.
研究领域:
能源存储
·
电池技术
·
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）