Carbon Capture Science & Technology
·
2023
·
IF 0
Xuan Wang,Yaoxing Wang,Xueqi Li,Jian Li,Yanjun Xie,Daxin Liang,Wentao Gan
Utilizing abundantly available biomass materials to prepare adsorbent substances is a simple and cost-effective method for CO 2 adsorption, which, however, is often hampered by low adsorption capacity. Here, we demonstrate near-spherical active carbon (C-DWP/Zn) with high CO 2 adsorption ability, employing delignification combination with ZnCl 2 activation of natural wood powder. Removing lignin from wood cell walls facilitates easy absorption of Zn ions by the cellulose nanofibers (CNFs), thereby promoting micro/nano pores formation. Moreover, rapid dehydration of cellulose molecular chains alters the morphology of activated carbon, resulting in a transition from a granular to a near-spherical shape. Consequently, C-DWP/Zn with high specific surface area of 1769 m 2 g −1 , shows a significantly higher microporous volume than that of a control sample without delignification. The CO 2 adsorption capacity of C-DWP/Zn, with values of 3.51 mmol g −1 and 5.12 mmol g −1 at 1 bar, 25 °C and 0 °C, respectively, is superior to that of commercial activated carbon. Attributable to its optimal micropore structure, C-DWP/Zn exhibits high CO 2 /N 2 selectivity. Furthermore, the high carbon dioxide adsorption efficiency of C-DWP/Zn was maintained and the substance could be reused at least 20 times. Near-spherical active carbon adsorbents prepared from low-value wood powders, all featuring high CO 2 adsorption performances, reasonable CO 2 /N 2 selectivity, good recoverability, suitable heat of adsorption, and fast adsorption kinetics, which are promising candidates for practical CO 2 adsorption.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2020
·Vol. 167
·期 4
·040505
·
IF 3.721
Longfei Qin,Zuoyi Xiao,Shangru Zhai,Shifu Wang,Haisong Wang,Guoxiang Wang,Weijie Cai,Zhongcheng Li,Qingda An
Biomass-derived hierarchical porous carbons have attracted considerable attention due to their low cost, environmental friendliness and sustainability. However, the preparation of porous carbon with typically hierarchical pores is still challengeable. In this work, a facile and efficient strategy was proposed to obtain alginate-derived porous carbon by a combination of hard-template and chemical-activation technique. During the fabrication process the nano-ZnO particles displayed triple functions: (a) The nano-ZnO particles were behaved as the hard template to generate more pores. (b) ZnCl2 derived from the nano-ZnO particles acted as a cross-linking agent for obtaining zinc alginate (Zn-SA) hydrogel beads. (c) ZnCl2 was also employed as an activating agent to form micropores during the high-temperature carbonization process. As a subsequence, the obtained carbon exhibited well-developed hierarchical porous structure with high specific surface area of up to 2589 m2 g−1. Due to the high specific surface area, good electrical conductivity and synergistic effect among the typically hierarchical pores, the PC-ZnO-ZnCl2-650 exhibited a high specific capacitance of 316 F g−1 at the current density of 0.5 A g−1 and excellent cycling stability with capacitance retention of 94.4% at 5 A g−1 over 5000 cycles. This ingenious synthesis strategy can provide a new way for efficient preparation of hierarchical porous material.
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
Materials
·
2024
·Vol. 17
·期 4
·942
·
IF 3.1
Hao Zhang,Zhaozhou Wei,Deyuan Xiong,Yao Wu,Menglong Tong,Huiping Su,Zuoyuan Zhang,Jian Liao
Using sodium lignosulfonate as feedstock, ZnCl2and NaHCO3co-activated the hierarchical porous carbons (HPCs) were prepared by one-pot pyrolysis with different NaHCO3dosages (0–4 g) and carbonization temperatures (400–600 °C). Subsequently, phosphotungstate (HPW) was supported with the resulting biochar for the α-pinene hydration reaction to produce α-terpineol. The optimum preparation conditions were determined according to the yield of α-terpineol. The formation mechanism and physicochemical properties of HPCs were analyzed through TG, SEM, XPS, XRD, FT-IR, and N2adsorption–desorption isotherms. The results demonstrated that NaHCO3underwent a two-step reaction which liberated a substantial quantity of CO2, thereby enhancing activated carbon’s macroporous and mesoporous structures. Simultaneously, NaHCO3mitigated strong acid gas (HCl) emissions during ZnCl2activation. Compared with AC450-4:8:0 prepared by ZnCl2activation alone, the total pore volume of AC450-4:8:2 prepared by co-activation is increased from 0.595 mL/g to 0.754 mL/g and the mesopore rate from 47.7% to 77.8%, which is conducive to reducing the steric hindrance of the hydration reaction and improving the selectivity. Hydration experiments show that the selectivity of α-terpineol is 55.7% under HPW/AC450-4:8:2 catalysis, higher than 31.0% for HPW and 47.4% for HPW/AC450-4:8:0.
研究领域:
材料科学
·
催化化学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2021
·Vol. 46
·期 2
·533-541
·
IF 3.591
Mei-Jiao Zeng,Xiaofeng Li,Shu-Meng Hao,Jin Qu,Wei Li,Jing Wu,Tianyu Zhao,Zhong-Zhen Yu
Although wood-derived carbon (WC) and its derivatives are promising electrodes for supercapacitors because of their hierarchically porous architecture, superior mechanical flexibility, and environmental friendliness, pure WC electrodes usually exhibit poor wettability, inferior areal capacitance, and unsatisfactory electrical conductivity. Herein, hierarchically porous graphene/wood-derived carbon (GWC) aerogels are fabricated for high-performance supercapacitor electrodes by chemical reduction of graphene oxide/wood hydrogels, followed by directional-freezing, freeze-drying, and carbonization at 1000 °C. An activated GWC (AGWC) anode is prepared by activating GWC using ZnCl2 to create more mass transport paths and increase wettability, while the cathode is synthesized by in situ growth of NiCo2O4 (NCO) in the channels of GWC to bring about pseudocapacitance and increase energy storage sites. The resultant NCO@GWC cathode and AGWC anode exhibit superior capacitances of 8540 and 10 965 mF cm−2 (854 and 183 F g−1) at 1 mA cm−2, respectively. The assembled NCO@GWC//AGWC asymmetric supercapacitor exhibits a superior areal capacitance of 7116 mF cm−2 at 1 mA cm−2, a high energy density of 2.2 mW h cm−2 (5.6 mW h cm−3), a power density of 45.1 mW cm−2 (112.8 mW cm−3), and an excellent cycling stability of 100% capacitance retention over 1000 cycles at 10 mA cm−2.
研究领域:
材料科学
·
能源存储与转换
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2011
·
IF 2.072
Juan Yang,Keqiang Qiu
Doehlert matrix was used to optimize the experimental conditions for the preparation of activated carbons from herb residues by vacuum chemical activation and traditional chemical activation using ZnCl2 as activation agent. The effects of activation temperature and impregnation ratio, the most influential factors of ZnCl2 chemical activation, were studied. The obtained activated carbons were characterized by total yield and methylene blue and iodine adsorption value. Each response has been described by a second-order model, and the predicted model presented a good agreement with experimental data. The results showed that activated carbons prepared by vacuum chemical activation have higher yield and better adsorption capacity. The removal percentages of methylene blue for the two optimal activated carbons and a commercial activated carbon were determined. The activated carbon prepared by vacuum chemical activation exhibited the highest methylene blue removal efficiency.
研究领域:
环境科学
·
材料科学
·
化学工程
·
资源循环利用
·
吸附技术
✓ 已验证
DOI
高影响因子
MOLECULES
·
2023
·Vol. 28
·期 3
·956
·
IF 4.6
Fangjie Lu,Qinqin Wang,Mingyuan Zhu,Bin Dai
The poor stability of carbon materials doped with nitrogen limited their development in acetylene hydrochlorination. Therefore, investigating the deactivation reasons of carbon catalysts and researching regeneration methods became the research focus. Herein, carbon-nitrogen materials were synthesized by one-step pyrolysis, which using biomass materials with high nitrogen content, the synthesized material was used in an acetylene hydrochlorination reaction. The acetylene conversion rate of D-GH-800 catalyst was up to 99%, but the catalytic activity decreased by 30% after 60 h reaction. Thermogravimetric analysis results showed that the coke content was 5.87%, resulting in catalyst deactivation. Temperature-programmed desorption verified that the deactivation was due to the strong adsorption and difficult desorption of acetylene by the D-GH-800 catalyst, resulting in the accumulation of acetylene on the catalyst surface to form carbon polymers and leading to the pore blockage phenomenon. Furthermore, based on the catalyst deactivation by carbon accumulation, we proposed a new idea of regeneration by ZnCl2activation to eliminate carbon deposition in the pores of the deactivated catalyst. As a result, the activity of D-GH-800 was recovered, and lifetime was also extended. Our strategy illustrated the mechanism of carbon deposition, and the recoverability of the catalyst has promising applications.
研究领域:
化学工程
·
催化
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry A
·
2018
·Vol. 6
·期 36
·17730-17739
·
IF 9.931
Rui Zhang,Xiangxia Jing,Yanting Chu,Lei Wang,Wenjun Kang,Denghu Wei,Haibo Li,Shenglin Xiong
A novel monolithic carbon sponge is prepared by a ZnCl2-assisted carbonization of commercial melamine foam (MF) at 800 °C in a N2 atmosphere. The as-prepared nitrogen/oxygen co-doped carbon sponges (NOCSs) can be directly applied as monolithic electrodes for supercapacitors without using any additives. It is found that ZnCl2 activation plays an important role in improving the supercapacitive behavior of NOCSs. Compared with the NOCS without ZnCl2 activation treatment, the optimal NOCS-1/10, obtained with a ZnCl2/MF weight ratio of 1 : 10, has the best capacitive performance due to its unique porous architecture, rich pseudocapacitance-active species, and good electron/ion transfer feature. It exhibits a high specific capacitance (242 F g−1 at a current density of 0.5 A g−1 and 325 F g−1 at a scan rate of 10 mV s−1) and good electrochemical cyclability (97% after 10 000 cycles at 5.0 A g−1). When being further assembled into an all-solid-state supercapacitor (PVA/KOH electrolyte), it can deliver an energy density of 4.33 W h kg−1 at a power density of 250 W kg−1 and 3.13 W h kg−1 at a power density of 3 kW kg−1.
研究领域:
材料科学
·
电化学
·
能量存储
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2017
·
IF 4.798
Chaozhong Guo,Rong Hu,Wenli Liao,Zhongbin Li,Lingtao Sun,Dongping Shi,Yanrong Li,Changguo Chen
Recycling and utilizing organic biowastes will effectively help to decrease the damage to the natural environment and synchronously facilitate the development of new carbon materials for energy applications. In this study, we directly convert protein-rich fish-scale biowaste to hierarchically porous three-dimentional (3D)-network nanocarbons via two-step pyrolysis process combined with ZnCl 2 activation and acidic-treatment. It is interestingly found that this material exhibits more excellent oxygen reduction electrocatalytic activity and stability compared to the commercial 20 wt% Pt/C catalyst in both alkaline and acidic solutions, which can be closely correlated to its chemical state of nitrogen atoms, BET surface area and inner porous structure. The addition of ZnCl 2 activator during pyrolysis process can help to produce the 3D network nanostructure and then to enhance the mesopore surface area, making for the improvement of oxygen reduction performance. More remarkably, the ORR onset potential on our material is about 60 mV higher than that on the Pt/C catalyst in alkaline electrolyte. In addition, we also propose that pyridinic- and graphitic-nitrogen species may be key factors to be responsible for the electrocatalytic activity. This study can encourage the exploration of high porosity nanocarbons from widely-existed biowastes, functioning as highly active and stable oxygen reduction electrocatalysts.
研究领域:
材料科学
·
环境科学
·
能源材料
·
电化学
✓ 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）