LANGMUIR
·
2023
·
IF 3.9
Yang Wu,Junhao Jing,Xiaojiang Li,Wenjian Yue,Jie Qi,Na Wang,Hongsheng Lu
A new form of surfactant-free microemulsion (SFME) including hydrophobic deep eutectic solvent (HDES)/ethanol/water was constructed based on its CO2 response, and three regions, that is, HDES-in-water (HDES/W), bicontinuous (B.C.), and water-in-HDES (W/HDES) regions, were recognized. It is anticipated that SFMEs with tunable microstructures have outstanding applications as nanoreactors in reaction processes. The feasibility of preparing nanoparticles from HDES/ethanol/water SFME using barium fluoride (BaF2) as a model nanoparticle was investigated. HDES-based microemulsions benefit from HDES’s excellent properties (novel, low toxicity, CO2-responsive, easy availability) and have potential in universal reactions, drug delivery, advanced material fabrication, etc. In this research, HDES-based microemulsions were prepared using HDES as the oil phase. Phase equilibria and microstructure were investigated using a ternary phase diagram, UV spectrophotometry, and the conductivity method. The CO2 switchable characteristics of the HDES-based microemulsions were investigated. HDES-based microemulsions were proposed as nanoreactors for the synthesis of barium fluoride nanomaterials. The microemulsion structure can modulate the size, morphology, and physicochemical properties of the nanoparticles through the CO2 switchable properties. It is argued that nanoreactors constructed with versatile HDES will offer a new direction for creation of cutting-edge scientific applications.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FUEL
·
2023
·
IF 7.4
Haripal Singh Malhi,Zhenzhou Zhang,Yanling Shi,Xinhua Gao,Wenqi Liu,Weifeng Tu,Yi-Fan Han
The multi-walled carbon nanotubes (MWNTs) supported Fe-based catalysts, including FeZnNa/MWNTs, FeZnK/MWNTs, and FeZnRb/MWNTs were synthesized through co-precipitation, and incipient wetness impregnation approaches. The physicochemical results demonstrated that the addition of MWNTs had significantly influenced the morphology, reduction, phase structure, adsorption behavior of Fe-based catalysts, and consequently, the reactivity of CO 2 hydrogenation to olefins. Furthermore, adding MWNTs to the alkali metal-promoted FeZn catalysts inhibits the synthesis of CH 4 and CO and favors an improved selectivity for olefins. With the incorporation of MWNTs, the heavy olefins (C 5- C 8 = ) selectivity over FeZnNa, FeZnK, and FeZnRb catalysts increased from 27.1 to 32.2, 27.0–31.1, and 24.2–28.6 %, respectively. The results proved that the superior selectivity of heavy olefin over the MWNTs-supported catalysts might be accomplished by the electron-donating ability of the MWNTs surface, the presence of extra Hägg carbide, and higher adsorption strength with light olefins. In addition, the catalyst supported by MWNTs demonstrated exceptional stability throughout the 100-hour test at 593 K.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF RARE EARTHS
·
2023
·
IF 4.9
Bolang Li,Fei Wang,Kai Li,Ping Ning,Min Chen,Changbin Zhang
The chemical transformation of CO 2 produces carbon compounds that can be used as precursors for the production of chemicals and fuels. Here, we investigated the activity and selectivity of the transition metals (Fe, Co, and Ni) supported on CeO 2 catalyst for CO 2 hydrogenation at atmospheric pressure. We found that Ni/CeO 2 shows the highest CO 2 conversion compared with Fe/CeO 2 and Co/CeO 2 . Besides, Co/CeO 2 and Ni/CeO 2 exhibit nearly 100% CH 4 selectivity while Fe/CeO 2 inclines to produce CO. The characterization results show that the metal-support interaction order is Fe/CeO 2 > Co/CeO 2 > Ni/CeO 2 , the weak metal-support interaction over Ni/CeO 2 benefits the activation of H 2 and then promotes the activity of CO 2 hydrogenation. Additionally, in situ DRIFTS results demonstrate that monodentate formate species rather than bidentate formate are the active intermediates. The main route of CO 2 hydrogenation to CH 4 is that CO 2 is firstly transformed to m-HCOO∗ and then direct hydrogenation of the m-HCOO∗ to CH 4 . This study provides insights into the understanding of the mechanisms of CO 2 hydrogenation on CeO 2 based catalysts.
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2023
·
IF 8.6
Wenting Wu,Zongqi Zhang,Lipeng Sun,Ruiping Wei,Lijing Gao,Xiaomei Pan,Jin Zhang,Jin Yu,Guomin Xiao
Well-arranged photosensitive units and catalytic sites in closeness are critical for enhancing charge separation effectiveness and promoting photocatalysis. Here, a heterogeneous interface is constructed, which binds a deprotonated carboxyl group on perylene diimide (PDI) photosensitizer to unsaturated metal sites generated by etching of different Prussian blue analogues (PBAs). The atomically-dispersed metal sites and anchored photosensitive units greatly accelerate charge transfer. Typically, the S-scheme heterojunction built by etched NiCo PBA and PDI (NCSP) possesses bond of O-Ni. Density functional theory (DFT) and in-situ technology reveals the electron density of the Ni active site is optimized. Consequently, activation barrier of CO 2 on the Ni site was reduced, thus improving the CO generation (60.0 μmol g −1 ) up to about 9 times than NiCo PBA. This work reveals key insights into the precise modulation of active moiety for efficient photocatalytic CO 2 conversion.
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2022
·Vol. 11
·期 4
·1793-1800
·
IF 14.511
Yu Nie,Tingting Bo,Wei Zhou,Huilin Hu,Xiang Huang,Huaiyuan Wang,Xin Tan,Lequan Liu,Jinhua Ye,Tao Yu
How to regulate the energy barrier of *COOH is the rate determining step of the photocatalytic reduction of CO2 to produce gaseous CO. Herein, an appropriate Zn vacancy on ZnIn2S4 was synthesised to achieve the desired photocatalytic CO2 reduction capacity (CO: 5.63 mmol g−1 h−1) and selectivity (CO: 97.9%). Various sulfhydryl groups were selected to regulate the Zn vacancy formation in ZnIn2S4, which directly generated the unsaturated coordination state of the sulfur adjacent to the Zn vacancy accompanied by less electrons when compared to ZnIn2S4 without Zn vacancy. Comprehensive experimental analysis and theoretical calculations demonstrated that the appropriate Zn vacancy tuned the Gibbs free energy of *COOH from the endothermic process to the exothermic process in the process of the photoreduction CO2. This work provided an engineering method for cation vacancies and improvement of the efficiency of photocatalytic CO2 reduction by adjusting the energy barrier of intermediate.
✓ 已验证
产品关联
DOI
高影响因子
Separations
·
2022
·Vol. 9
·期 12
·428
·
IF 3.344
Zhen Wang,Chenteng Sun,Qian Xu,Xingli Zou,Hongwei Cheng,Xionggang Lu
Sodium silicate, a new type of CO2sorbent, has a relatively low cost, but its sorption reactivity is not yet good enough. Alkali carbonate doping is commonly used as an effective means to improve the CO2uptake reactivity of solid sorbents. In this study, sodium orthosilicate, Na4SiO4, was synthesized and mixed with 5, 10, and 20 mol% of Li2CO3–Na2CO3or Li2CO3–Na2CO3–K2CO3as CO2sorbents. The promotion of alkali carbonates on Na4SiO4in CO2capture was characterized using thermal analyses in an 80 vol% CO2–20 vol% N2atmosphere. The phase evolution and structural transformations during CO2capture were characterized by in situ XRD and Raman, and the results showed that the intermediate pyrocarbonate, C2O52−, which emerged from alkali carbonates, enhanced the CO2capture of Na4SiO4to form Na2CO3and Na2SiO3from 100 °C. Isothermal analyses showed that 10 mol% of Li2CO3–Na2CO3was the optimal additive for Na4SiO4to attain better CO2uptake performance. The alkali carbonates were effective in reducing the activation energy for both chemisorption and bulk diffusion, improving the cycle stability of Na4SiO4.Keywords:CO2capture;Na4SiO4;alkali carbonates;in situ XRD;in situ Raman;isothermal analysis;double exponential model;Eyring’s model
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2022
·
IF 8.035
Leilei Xu,Chunying Xu,Bin Chen,Yufang Bian,Xueying Wen,Ge Cheng,Cai-e Wu,Jian Qiu,Mindong Chen
In this work, a series of hexagonal mesoporous silica (HMS) confined Ni-based CO 2 methanation catalysts were successfully synthesized by the facile one-pot strategy. In the Ni-HMS system, the metallic Ni active sites were embedded in the framework of HMS support. Hence, the metallic Ni active sites were highly dispersed and stably confined by the HMS framework. The kinetic study demonstrated that the Ni-HMS catalysts behaved much lower apparent activation energy than the 15Ni/HMS and 15Ni/SiO 2 catalysts, accounting for their enhanced low-temperature activities. Meanwhile, the online TPSR and in-situ DRIFTS of the CO 2 methanation were employed to study the reaction intermediates over these catalysts. The CHOO–, CH x O-, and CO x were considered as the reaction intermediates over the Ni-HMS catalysts and the possible reaction pathways were also proposed. In conclusion, the Ni-HMS catalysts were considered as a series of efficient and stable catalyst candidates for CO 2 methanation.
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2023
·
IF 6.6
Jiamin Li,Haochen Shen,Chenxi Ma,Hao Zhang,Peng Luo,Junteng Chen,Manman Mu,Xiaohong Yin
Electrocatalytic reduction of CO 2 (CO 2 RR) into value-added chemicals is a promising approach to alleviate environmental issue, but the efficiencies of electrocatalysts are limited by the poor conductivity, low current density and large overpotential. Herein, two-dimensional bimetallic porphyrin-based conjugated cobalt MOF (Co-(Co+Cu) PMOF) is deposited on g-C 3 N 4 nanosheets to construct g-C 3 N 4 @Co-(Co+Cu)PMOF which enhances electron transfer from g-C 3 N 4 to Co-(Co+Cu)PMOF. Benefiting from its larger capacitance and faster charge transfer rate than g-C 3 N 4 and Co-(Co+Cu)PMOF, g-C 3 N 4 @Co-(Co+Cu)PMOF-50% exhibits superior catalytic activity with a high Faradaic efficiency of CO (97.8%) and large current density of -2.1 mA•cm −2 at -1.4 V compared with pristine Co-(Co+Cu)PMOF and other porphyrin-based MOF analogues. The high performance might ascribe that Co centers in porphyrin rings acquire more electrons to activate CO 2 which can be converted to intermediate *COOH through evidences from the experimental results and theoretical calculations. This work provides a new insight into the rational design of electrocatalysts for the CO 2 RR using porphyrin-based conjugated MOFs.
✓ 已验证
产品关联
DOI
高影响因子
Journal of CO2 Utilization
·
2023
·
IF 7.7
Jiaxin Liang,Siyuan Wang,Change Wu,Shuanjin Wang,Dongmei Han,Sheng Huang,Zhiheng Huang,Min Xiao,Yuezhong Meng
Poly(propylene carbonate phthalate) (PPC-P) is a new biodegradable polymer which displays improved thermal and mechanical properties compared with poly(propylene carbonate) (PPC). However, PPC-P suffers from low melt viscosity at high temperature, restraining its applications in foaming and blowing materials. To address this issue, crosslinkable PPC-P is designed and synthesized by introducing vinyl moieties into PPC-P backbone. Later, the crosslinking conditions are optimized and the influences on the crosslinking density is investigated. The crosslinked PPC-P possesses tailorable melt flow rates, basically unchanged thermal properties and improved tensile performances as well as satisfactory transparency, laying a foundation for PPC-P to be applied as foaming and blowing materials.
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2022
·
IF 9.136
Qinlan Luo,Yan Ouyang,Shumin Hong,Nan Wang,Yuanyuan Li,Hongxia Gao,Gyeong S. Hwang,Bohak Yoon,Teerawat Sema,Paitoon Tontiwachwuthikul,Peng Luo,Chintana Saiwan,Zhiwu Liang
To explore the regulatory factor of phase separation and the effect of solvent structure, the phase separation behavior, absorption/desorption performance, viscosity change, heat duty and ternary phase diagram of 3 monoethanolamine(MEA)-based phasic absorbents using 3 alcohols with various carbon chain lengths and isomers were determined by comprehensive experiments. The tunable phase separation behavior of MEA-based biphasic absorbents can be achieved by adjusting the mass concentration ratio of solvent and water, and the CO 2 loading of phase separation point was much more impacted by the effect of the carbon chain length than that of isomerism. The intermolecular interactions between species in solutions before and after CO 2 absorption were analyzed by the classical molecular dynamics simulations and independent gradient model analysis. Based on the experimental and computational results, the fundamental mechanism of phase separation was elucidated, which is related to the broken of hydrogen bonds between solvent with H 2 O or MEA, and the enhanced interaction among MEACOO − , MEAH + and H 2 O. This study highlights the effect of structure effect on developing advanced CO 2 biphasic absorbents, which may reduce the energy consumption of regeneration significantly.
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2023
·
IF 7.7
Haopeng Jiang,Mengyang Xu,Xiaoxue Zhao,Huiqin Wang,Pengwei Huo
The electron density on the catalyst surface has a great influence on the multi-electron transport process of photocatalytic reduction of CO 2 . In this work, hierarchical Cu 2 O/Ni-MOF composite photocatalyst with local surface plasmon resonance (SPR) properties was prepared by simple hydrothermal and water bath methods. Through DRS, XPS and AES tests found that the SPR of Cu 0 expanded the light absorption , provided hot electrons for the reaction system, and greatly improved the photocatalytic activity in coordination with the hierarchical structure and heterostructure. In the absence of sacrificial agent, the CO yield of 30%-Cu 2 O/Ni-MOF was 4.1 times of Cu 2 O (5.32 μmol/g) and 11.1 times of Ni-MOF (1.95 μmol/g), respectively. Then, the possible photocatalytic reaction path was simply speculated based on in-situ FT-IR. In conclusion, the hierarchical structure, heterostructure and SPR effect accelerate the kinetics of Cu 2 O/Ni-MOF photocatalytic reaction, thus improving its photocatalytic activity.
✓ 已验证
产品关联
DOI
高影响因子
GREEN CHEMISTRY
·
2022
·Vol. 25
·期 1
·130-152
·
IF 11.034
Yu Xie,Junjie Wen,Zonglin Li,Jianjun Chen,Qiulin Zhang,Ping Ning,Yaoqiang Chen,Jiming Hao
With the development of carbon dioxide (CO2) capture, storage and utilization (CCSU) technologies, CO2 has gradually become a desired feedstock for the production of value-added chemicals like methane (CH4). Ceria (CeO2)-based catalysts have gained much attention because of their potential to efficiently hydrogenate CO2 to CH4 under mild conditions. Here we systematically outline the advances in CeO2-based catalysts for CO2 methanation mainly from the perspective of mechanism investigation and catalyst development. Various in situ/operando and ex situ technologies have verified that active metal and oxygen vacancies at the metal/metal oxide–CeO2 interface act as the prime active sites to promote the formation and hydrogenation of key intermediates during the CO2 methanation reaction. Kinetic analysis and in situ DRIFT characterization combined with theoretical calculations revealed that the reaction mechanism toward CO2 methanation is sensitive to active sites, and the formate route versus the carboxyl (CO*) route has been widely detected as the main methanation pathway over CeO2-based catalysts. Additionally, mainstream strategies to improve CeO2-based catalysts include optimizing reducibility, adjusting the distribution of basic sites, dispersing active metal supported on CeO2, and increasing the amount of oxygen vacancies or additional active sites for CO2 adsorption and selective hydrogenation into CH4. Finally, perspectives on the deeper understanding of active sites and intermediates’ evolution and the challenges of CeO2-based catalysts for CO2 methanation in future investigations are presented.
✓ 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）