Materials Today Communications
·
2024
·
IF 3.7
Lianqing Yu,Wenjing Xie,Xiaomeng Ji,Yaping Zhang,Haifeng Zhu
The availability of low-cost precious metal-free photocatalysts is critical for sustainable and large-scale hydrogen production. Constructing heterojunctions is considered as an effective strategy to enhance the transfer/separation of photo-induced charges. Nanoflower structures of ZnCdS can significantly enhance light absorption and increase the specific surface area available for reactions involving photo-generated carriers. Herein, MoS 2 are attached to ZnCdS nanoflowers through electrostatic adsorption, forming a ZnCdS-MoS 2 composite photocatalyst for hydrogen evolution reaction (HER). Under visible light irradiation, the ZCS-MoS 2 -8 % photocatalyst demonstrates an impressive photocatalytic HER rate of 42.07 mmol·h −1 ·g −1 , which is 5.8 times higher than that of the pure ZnCdS photocatalyst (outperforming many reported results). The MoS 2 nanocrystals greatly benefit the transfer of photoinduced electrons to ZnCdS for proton reduction and facilitate the transfer of holes for water oxidation. The constructed ZnCdS-MoS 2 photocatalyst for hydrogen evolution shows promising chemical and economic value.
研究领域:
材料科学
·
能源化学
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DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
·
2018
·
IF 3.956
Longfei Tang,Songjiang Chen,Shiwei Wang,Xiuxiang Tao,Huan He,Lei Zheng,Chenyan Ma,Yidong Zhao
The present work investigated the feasibility of heterocyclic sulfur (HS) removal for coal utilizing potassium tert-butoxide and hydrosilane system. Changes of sulfur forms with treatment time in Xinyu (XY) coal were determined by XANES . Results showed that reductions of total sulfur and organic sulfur for XY coal were 55% and 53%, respectively. >85% sulfoether and thiophene sulfur were removed after treated for 4 h, suggesting that the HS could be removed to a high extent from coal. However, contents of sulfonate and sulfonic ester increased with treatment time due to the hydrolysis and oxidation of intermediate products containing Si S bands. Furthermore, it indicated that the HS could be removed selectively from coal without destroying the macromolecular structure of coal based on analysis of desulfurization mechanism. These findings suggested that the desulfurization of refractory HS in coal could be obtained using the potassium tert-butoxide/hydrosilane reductive system, which provided a reference for desulfurization of high organic sulfur coal .
研究领域:
能源化学
·
煤化工
·
环境化学
·
应用化学
·
清洁燃料技术
✓ 已验证
DOI
高影响因子
FUEL
·
2020
·
IF 5.578
Bowen Lu,Zewu Zhang,Xiaoshan Li,Cong Luo,Yongqing Xu,Liqi Zhang
Cu catalysts have been widely used in CO 2 utilization due to their low reduction temperature and excellent CO 2 hydrogenation performance. It is important to well design Cu catalyst with high efficiency and durability for CO 2 hydrogenation. In this work, CuCe(rod) catalysts with various Cu contents were prepared. The physicochemical properties of the CuCe(rod) catalysts were described by XRD, TEM, N 2 -physisorption and H 2 -TPR.The effect of Cu content on catalytic performance of CO 2 hydrogenation with CuCe(rod) catalysts was also studied. Results showed that a high Cu content enhanced CO 2 conversion. The 40CuCe(rod) catalyst exhibited the best CO 2 conversion performance. At the reaction temperature of 400 °C, the CO production rate (CO 2 conversion) and CO selectivity based on the 40CuCe(rod) catalyst could reach 1.69 mol/g cat /h (41.1%) and nearly 100%, respectively. The analysis of kinetic measurements revealed that the activation energy of the 40CuCe(rod) catalyst was lower than that of other catalysts with different Cu contents during a reverse water–gas shift reaction. The lower activation energy and the interface structure of Cu-O x -Ce were closely related to CO 2 hydrogenation activity and remarkable stability for 96 h with minimal loss of CO 2 conversion activities.
研究领域:
化学工程
·
环境科学
✓ 已验证
DOI
高影响因子
FLUID PHASE EQUILIBRIA
·
2022
·
IF 2.745
Feng Liu,Li Chen,Kangling Yin,Taotao Fan,Zongcheng Yan
In this work, a novel liquid–liquid biphasic system of sugar-based deep eutectic solvents (DESs) was studied. The liquid–liquid biphasic system was formed when sugar-based DESs and n-propanol (NPA) showed incompatibility in an aqueous solution at above critical concentrations and 298.15 K. The DESs were prepared by choline chloride and sugars (sucrose, glucose, fructose, and xylose). The influence of the hydroxyl group and structure of HBD on the phase behavior was evaluated using phase diagrams and tie-lines length (TLL). Results showed that the biphasic region of DESs-based system was expanded by enhancing the hydrophilic of HBD. Each HBD (sucrose, glucose, fructose) and choline chloride can form ternary system with NPA and water. With this phase behavior, the molar ratio of DESs in two phases is the same as the original ratio of the DES formation. A non-random two-liquid (NRTL) model was used to correlate the tie-lines data of the systems, and the binary interaction parameters of the model were then obtained. Shikimic and vanillic acids used as biomolecule probes in two phases was studied to further explore the extraction potential of these DES-based systems. This work showed that the nature of HBDs influences the distribution behavior of shikimic and vanillic acids. And the DES-based systems presented higher extraction efficiencies (from 88.02% to 91.90%) for shikimic acid, which shows good extraction levels.
研究领域:
化学工程
·
生物技术
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DOI
高影响因子
CRYSTENGCOMM
·
2022
·Vol. 24
·期 46
·8060-8069
·
IF 3.756
Shu-Qin Qin,Wei Xu,Wen-Cai Ye,Ren-Wang Jiang
Guanidinium–naphthalenedisulfonic acid (GNPS) was used as a molecular catcher because (i) it contains a cavity and channel in the network; (ii) NH2+ can be used as a hydrogen bond donor, and SO3− can be used as a hydrogen bond acceptor; (iii) the co-planar naphthalene rings can form aromatic interactions with guest molecules. The liquid guests 1–8 [(−)-isopulegol (1), (−)-menthyl acetate (2), isoeugenol (3), 2,6-dimethylaniline (4), methyleugenol (5), 2,6-diisopropylaniline (6), methyl salicylate (7) and L(−)-carvone (8)] are successfully encapsulated in the cavity of GNPS and eight new crystals were obtained. Both aromatic and non-aromatic molecules form hydrogen bonds and C–H⋯π interactions with GNPS. Co-crystallization of 1–4 with GNPS led to stronger C–H⋯π interactions as compared to the previously reported GBPS. Furthermore, compounds 5–8 which were not co-crystallized with GBPS were found to be encapsulated in the cavity of GNPS. We found that the aromatic cavity of GNPS with hydrogen bonding and enhanced C–H⋯π interactions can be regarded as a useful tool for the structural determination of liquid molecules. Furthermore, the correct absolute configurations of 1, 2 and 8 can be assigned based on the small Flack parameters because of the presence of sulfur atoms in the host molecule GNPS.
研究领域:
化学晶体学
·
分子结构分析
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材料科学
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DOI
高影响因子
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
·
2014
·Vol. 71
·期 3
·597-605
·
IF 1.547
Zhang Hui,Zhan Kan,Chen Yulu,Chen Guoxia,Zhou Xiaomei,Liu Junxiu,Wu Min,Ni Henmei
Three dimensional Liesegang spherical layers of CaHPO 4 in gelatin ball were performed by employing CaCl 2 and Na 2 HPO 4 as the inner and outer electrolyte, respectively. Effects of concentrations of inner and outer electrolyte as well as pH on the morphologies of Liesegang rings (LRs) were investigated. As a result, it was observed that the time law, spacing law and width law found in 1D/2D gel systems were obeyed in this 3D gelatin system. The interaction of Ca 2+ and HPO 4
2− with gelatin matrix played a key role to the formation of LRs due to the existence of carboxylic groups on the gelatin chains. Using Ca 2+ as the inner electrolyte, LRs were prepared. However, employing HPO 4
2− as inner electrolyte, LRs were not obtained. Moreover, pH of gelatin solution greatly impacted on the formation of LRs. The number of LRs increased with the decrease of pH, whereas the width inversely decreased. pH 4.40 was a turn point, from which the spacing coefficient abruptly increased as pH increased. All these results indicated that the network was created by the interaction of Ca 2+ and –COO − of gelatin chains, which dominated the formation of CaHPO 4 LRs in gelatin.
研究领域:
生物材料学
·
物理化学
·
软物质物理
·
胶体科学
·
生物矿化
✓ 已验证
DOI
高影响因子
CRYSTENGCOMM
·
2020
·Vol. 22
·期 23
·4030-4038
·
IF 3.117
Jin Yan,Lei Dai,Penghui Shi,Jinchen Fan,Yulin Min,Qunjie Xu
A limited light absorption range and low electron transfer efficiency have always been the major problems in semiconductor photocatalysis. Here, a defect-rich heterophase junction-containing TiO2 porous nanostructure was designed and synthesized to improve the low utilization rate of photoexcited carriers in photocatalysis. Defects were first introduced into titanium dioxide, and co-doping was used to obtain defect-rich materials. At the same time, heterophase junction TiO2 with anatase and rutile phases was obtained under temperature control. The TiO2 phase junction could significantly improve the interface charge recombination. These two synergistically regulated the hydrogen production favorably, thus improving the carrier separation efficiency and reducing the band gap from the ultraviolet to the visible region, which resulted in the construction of the most effective defects. Theoretical predictions and empirical characterizations indicate that TiO2 with defects introduced into it presents a porous structure, and the doped phase exposes the internal defects of the bulk phase of the material to the surface and adjusts the defect position. The experimental results confirmed that the synergistic effect of B and Rh co-doping increased the photocatalytic hydrogen production yield of TiO2 by 10 times. This study provides new insights into photocatalyst defect regulation.
研究领域:
材料科学
·
纳米技术
·
能源化学
·
光催化
·
半导体物理
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DOI
高影响因子
CHINESE JOURNAL OF POLYMER SCIENCE
·
2015
·Vol. 33
·期 10
·1431-1441
·
IF 1.835
Zhao Wen,Lin Bao-ping,Zhang Xue-qin,Sun Ying,Yang Hong
We describe in this work an alkyne-hydrosilylation approach to synthesize a series of novel polysiloxane side-chain LCPs attaching end-on or side-on mesogenic side groups. Their properties are characterized by NMR, FTIR, gel permeation chromatography, thermogravimetric analysis, differential scanning calorimetry, polarized optical microscopy and small-angle X-ray scattering. These obtained alkenylsilane linked novel LCPs exhibit higher glass transition temperatures and clearing points, and especially display the tendency of forming smectic phases, in strong contrast with the nematic phases of their comparative conventional alkylsilane linked analogues, which manifests more rigid features of the alkenylsilane linkages and their significant influence on the mesomorphic properties.
研究领域:
高分子化学
·
材料科学
·
液晶材料
·
有机合成
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2022
·
IF 12.92
Huapeng Li,Bin Sun,Tingting Gao,Huan Li,Yongqiang Ren,Guowei Zhou
ABSTRACT Photocatalytic degradation and hydrogen production using solar energy through semiconductor photocatalysts are deemed to be a powerful approach for solving environmental and energy crisis. However, the biggest challenge in photocatalysis is the efficient separation of photo-induced carriers. To this end, we report that the mesoporous TiO 2 nanoparticles are anchored on highly conductive Ti 3 C 2 MXene co-catalyst by electrostatic self-assembly strategy. The constructed mesoporous TiO 2 /Ti 3 C 2 composites display that the mesoporous TiO 2 nanoparticles are uniformly distributed on the surface of layer structured Ti 3 C 2 nanosheets . More importantly, the as-obtained mesoporous TiO 2 /Ti 3 C 2 composites reveal the significantly enhanced light absorption performance, photo-induced carriers separation and transfer ability, thus boosting the photocatalytic activity . The photocatalytic methyl orange degradation efficiency of mesoporous TiO 2 /Ti 3 C 2 composite with an optimized Ti 3 C 2 content (3 wt%) can reach 99.6% within 40 min. The capture experiments of active species confirm that the •O 2 − and •OH play major role in photocatalytic degradation process. Furthermore, the optimized mesoporous TiO 2 /Ti 3 C 2 composite also shows an excellent photocatalytic H 2 production rate of 218.85 μmol g –1 h –1 , resulting in a 5.6 times activity as compared with the pristine mesoporous TiO 2 nanoparticles . This study demonstrates that the MXene family materials can be applied as highly efficient noble-metal-free co-catalysts in the field of photocatalysis .
研究领域:
材料科学
·
环境科学
·
能源科学
✓ 已验证
DOI
高影响因子
Crystals
·
2023
·Vol. 13
·期 2
·342
·
IF 2.7
Yang Yu,Yuzhen Zhao,Yongsheng Mi,Fengmei Fang,Huimin Zhang,Zhun Guo,Yang Zhao,Dong Wang
A symmetrical pyrene derivative chemical structure was prepared by a classical synthetic method such as the Sonogashira cross-coupling reaction. The molecular structure of the product was characterised in detail by nuclear magnetic resonance (NMR), mass spectrometry (MS) and other methods. Furthermore, the optical properties of the novel products were studied by UV-vis and photoluminescence spectroscopy. The electrochemical properties of the molecules were fully characterised by comparison of electrochemical experiments and DFT simulation. Scanning electron microscope (SEM) observed that the product successfully formed a regular self-assembly structure. The product verifies the role of the molecular structure of the disc-mounted molecules on the optical and self-assembly properties, and is of reference value in the field of organic optoelectronic molecules
研究领域:
有机化学
·
材料科学
·
光电子学
✓ 已验证
DOI
高影响因子
JOURNAL OF THE ENERGY INSTITUTE
·
2024
·
IF 5.6
Mingxuan Zhong,Chenxuanzi Wang,Jiajun Xu,Yongcheng Cai,Bo Xiao,Tingting Xu,Xun Wang
Sr–Fe oxides are suitable oxygen carriers (OCs) with excellent cyclic stability. However, the moderate redox activity causes a deficiency in H 2 yield in chemical looping reforming coupled with water splitting (CLR-WS) process. Herein, we designed and prepared the composite xNiFe 2 O 4 /(1-x)SrFe 12 O 19 OCs by ball milling method, which exhibited both high redox activity and high cyclic stability during reactions. A series of characterizations showed that the introduction of NiFe 2 O 4 promoted the oxygen vacancy formation and the release of lattice oxygen, facilitating the reforming of bioethanol in fuel reactor (FR). During CLR-WS process, a high carbon conversion of 79.20 % and a H 2 yield of 13.23 mmol/g OC were achieved by 3Ni7Sr OC at 800 °C, outperforming that of the conventional SrFe 12 O 19 OC. Moreover, the severe carbon deposition and sintering issues inherent to NiFe 2 O 4 were avoided due to the presence of Sr. All Sr-containing composite OCs showed H 2 purity exceeding 99.26 % and excellent cycling stability with no apparent activation of oxygen transport capacity over 3000 min redox reactions.
研究领域:
化学工程
·
材料科学
·
能源工程
·
环境工程
✓ 已验证
DOI
高影响因子
Nano Research
·
2024
·Vol. 17
·期 6
·4898-4907
·
IF 9.5
Geng Jing,Ji Sihan
Electrocatalytic nitrate ( \({\rm{N}}{{\rm{O}}_3}^ -\) ) reduction to ammonia (NH 3 ) offers a viable approach for sustainable NH 3 production and environmental denitrification. Copper (Cu) possesses a distinctive electronic structure, which can augment the reaction kinetics of \({\rm{N}}{{\rm{O}}_3}^ -\) and impede hydrogen evolution reaction (HER), rendering it a promising contender for the electrosynthesis of NH 3 from \({\rm{N}}{{\rm{O}}_3}^ -\) . Nevertheless, the role of Cu 2 O in copper-based catalysts still requires further investigation for a more comprehensive understanding. Herein, the Cu 2 O/Cu(OH) 2 heterostructures are successfully fabricated through liquid laser irradiation using CuO nanoparticles as a precursor. Experimental and theoretical researches reveal that Cu 2 O/Cu(OH) 2 heterostructure exhibits enhanced electrocatalytic performance for \({\rm{N}}{{\rm{O}}_3}^ -\) to NH 3 because Cu(OH) 2 promotes electron transfer and reduces the valence state of Cu active site in Cu 2 O. At −0.6 V (vs. reversible hydrogen electrode (RHE)), the NH 3 yield reaches its maximum at 1630.66 ± 29.72 \({\rm{\mu g}} \cdot {{\rm{h}}^{ - 1}} \cdot {\rm{m}}{{\rm{g}}_{{\rm{cat}}}}^{ - 1}\) , while the maximum of Faraday efficiency (FE) is 76.95% ± 5.51%. This study expands the technical scope of copper-based catalyst preparation and enhances the understanding of the electrocatalytic mechanism of \({\rm{N}}{{\rm{O}}_3}^ -\) to NH 3 .
研究领域:
电化学
·
催化
·
环境科学
·
纳米材料
·
能量转换
·
表面化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）