Surfaces and Interfaces
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2023
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IF 6.2
Tingyu Chen,Shuaiqi Zhao,Jiajin Lin,Yanan Chong,Yifei Li,Yun Zhao,Guangxu Chen,Yongcai Qiu
As a nontoxic and cheap catalyst, the Al 2 O 3 catalyst can be used to catalyze the propane dehydrogenation (PDH) process. However, due to its poor activity, it has been used as a catalyst carrier rather than catalysis. In this work, the experimental results indicate that γ- Al 2 O 3 -(110)-S catalysts can improve the yield of propane dehydrogenation more effectively than γ-Al 2 O 3 -(110) catalyst. We investigate the potential barrier of propane dehydrogenation reaction catalyzed by Al 2 O 3 -(110) under different conditions and found that the substitution of the S atom for partial O atom can modify the acid-base properties of the surface active site of γ-Al 2 O 3 -(110), thus reducing the reaction energy barrier. In particular, the yield of the reaction can be further improved by the active sites of oxygen vacancies generated by removing partial S atoms in γ-Al 2 O 3 -(110)-S, which is consistent with our theoretical calculation results. At the same time, theoretical calculation shows that Cu clusters can effectively remove the S atoms on the surface of γ-Al 2 O 3 -(110)-S and form oxygen vacancies. This strategy provides a new path to form oxygen vacancies on γ-Al 2 O 3 -(110), which opens up a new way for the study of propane dehydrogenation.
研究领域:
催化化学
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材料科学
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产品关联
DOI
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2025
·
IF 3.5
Kexin Li,Huifang Zhang,Mingzhe Dong,Zhongmei Song,Mingzhen Li,Chunyan Wang,Haining Liu,Xiushen Ye,Guosheng Shi,Zhijian Wu
Anhydrous magnesium chloride is a conventional raw material for the electrolytic production of magnesium metal. Its preparation contributes about 50 % of the overall cost of the electrolytic production of magnesium metal. The search for a new process for the preparation of anhydrous magnesium chloride at a low cost has attracted much attention. In this study, the effects of graphene on the pyrolysis of MgCl 2 ⋅6H 2 O were investigated by comparing the thermal decomposition processes of MgCl 2 ·6H 2 O and MgCl 2 ·6H 2 O-graphene, using TG, DTG, DSC, XRD, FTIR techniques and theoretical calculations. It was found that the addition of graphene can reduce the energy barrier for the pyrolysis of MgCl 2 ⋅6H 2 O, accelerate the pyrolysis reactions, reduce the reaction temperature and energy consumption. The cation-π interactions between graphene and Mg 2+ , and the good thermal conductivity of graphene accelerate the thermal decomposition. The results obtained would be helpful for understanding the decomposition processes and mechanisms of MgCl 2 ·6H 2 O under the assistance of graphene, and for exploring new techniques for MgCl 2 ·6H 2 O dehydration.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
Surfaces and Interfaces
·
2024
·
IF 5.7
Hele Hua,Nan Zhang,Zhidan Wang,Rui Li,Yunfang Wang,Jianxin Liu,Peide Han,Caimei Fan,Yawen Wang
Electrocatalytic NO 3 − reduction reaction (NO 3 RR) has attracted much attention as a promising NH 3 synthesis pathway, and Cu-based catalysts have been proven to lead to advantages in nitrate reduction . However, the active hydrogen (H*) produced by the Cu-based catalyst is insufficient to satisfy the hydrogenation process of the NO 3 RR intermediate, resulting in a large generation of NO 2 − . In this paper, the Co(OH) 2 /Cu 2 O heterojunction was constructed to improve the kinetics of H 2 O dissociation to generate H* and Co(OH) 2 /Cu 2 O (5.87 %) showed lower faradaic efficiency (FE) of NO 2 − than Cu 2 O (50.95 %). Mechanistic studies reveal that the introduction of Co(OH) 2 can help Cu 2 O lower the energy barrier of H 2 O dissociation, greatly boosting the supply of active hydrogen (H*). Not only that, but the reaction energy barriers of *NO to *NOH can be greatly reduced. The final twofold reason works together to greatly improve the efficiency of hydrogenation of NO 2 − , largely solving the problem of FE reduction due to the delayed consumption of NO 2 − , thus realizing improved performance.
研究领域:
化学
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材料科学
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催化
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产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2020
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IF 8.758
Xinyi Chen,Wen Shi,Kun Zhang
Without sacrificing the intrinsic softness and flexibility of conducting polymers, their blends have been demonstrated to be promising to improve thermoelectric properties of conducting polymers. However, the underlying mechanism for the thermoelectric enhancement is hitherto far from clear and is worthy of being explored deeply. In this work, we report novel conducting polymer nanowire blends by physically mixing poly(3,4-ethylenedioxythiophene) (PEDOT) nanowires and polypyrrole (PPy) nanowires. By carefully tuning the energetic structure of PPy nanowires (nanofillers), the Seebeck coefficients and power factors of nanowire blends are surprisingly increased by ∼20 and ∼32% (compared to PEDOT nanowires), respectively. By means of first-principles calculations and experimental characterizations, we qualitatively confirm that the improved thermoelectric property is a consequence of a built-in energy barrier at nanowire interfaces rather than the commonly used doping/de-doping effect. Subsequently, we further employ the Kang–Snyder transport model and quantitatively demonstrate that the energy barrier involves energy-dependent carrier scattering (thus, a change of total relaxation time) at nanowire heterojunctions, which contributes to the enhanced Seebeck coefficients and power factors. Our work sheds light on the mechanism that can be adopted to design soft but high-performance thermoelectric materials with conducting polymer blends.
研究领域:
材料科学
·
物理学
✓ 已验证
DOI
高影响因子
Energy Storage Materials
·
2023
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IF 20.4
Liping Duan,Haowei Tang,Xifan Xu,Jiaying Liao,Xiaodong Li,Guangmin Zhou,Xiaosi Zhou
Potassium-ion batteries (PIBs), with their high theoretical energy density and abundant natural resources , are emerging as one of the most promising candidates for next-generation energy storage systems . Nevertheless, they suffer from large volume expansion and sluggish K + transport due to the huge ionic radius of K + , resulting in limited cyclic life and rate performance. Therefore, accelerated transport kinetics may be the key to designing electrodes with excellent potassium storage properties. Herein, we develop a new synthetic method to in-situ construct a high-efficiency PIB cathode, N-doped P3-typed K 0.5 Mn 0.67 Fe 0.33 O 1.95 N 0.05 nanosheets (denoted KMFON), using the low cost Prussian blue analogue Mn 2 [Fe(CN) 6 ] as a precursor. Combining experimental results and theoretical calculations, the as-synthesized KMFON exhibits large interlayer spacing, small K + migration energy barrier, high electronic conductivity , and fast K + transport kinetics, which are attributed to the larger-sized N substitution O. It also manifests an initial reversible capacity of 104.2 mAh g −1 at 20 mA g −1 , a rate capability of 41.5 mAh g −1 at 500 mA g −1 , and a high discharge capacity of 52.2 mAh g −1 after 300 cycles at 100 mA g −1 . Moreover, the KMFON//pitch-derived soft carbon full cell exhibits a satisfactory rate performance of 49.4 mAh g −1 at 200 mA g −1 and a good cycling performance of 46.8 mAh g −1 after 200 cycles at 100 mA g −1 , indicating the great potential of KMFON as a cathode material for PIBs.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
Energy Storage Materials
·
2022
·
IF 20.831
Pengxiang Lin,Jianlong Cong,Jiyang Li,Minghao Zhang,Pengbin Lai,Jing Zeng,Yang Yang,Jinbao Zhao
Aqueous zinc-ion batteries (ZIBs) have received extensive attention due to the intrinsic advantages of high safety, low cost and environmental friendliness. But detrimental side reactions and dendrite problems resulting from high desolvation penalty and inhomogeneous Zn 2+ flux at the interface severely hindered their practical applications. Herein, a novel polyacrylamide-poly (ethylene glycol) diacrylate-carboxymethyl cellulose (PMC) hydrogel electrolyte is designed to overcome these obstacles through reducing the desolvation energy barrier and guiding the preferential orientation of Zn deposition simultaneously. Theoretical calculation and experimental results reveal that the desolvation activation energy of the PMC hydrogel electrolyte (36.42 kJ mol −1 ) is substantially lower than that of conventional ZnSO 4 aqueous electrolyte (62.31 kJ mol −1 ) due to the regulated Zn 2+ solvation structure. Based on the high binding energy between amide groups and Zn 2+ , polymer chains in PMC also serve as facile Zn 2+ transport channels to guide the uniform deposition behavior on the Zn (002) crystal surface, which is verified by the grazing incidence XRD analysis . Consequently, an ultra-long cycle life of 5000 h with a high coulombic efficiency of 99.5% is achieved by using the PMC hydrogel electrolyte. Considering the simple one-pot synthesizing method, the PMC hydrogel electrolyte provides new opportunities for developing practical ZIBs .
研究领域:
材料科学
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电化学
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能源存储
✓ 已验证
DOI
高影响因子
ACS Nano
·
2025
·
IF 16
Shikang Jiang,Yuqiu Wang,Hao Ge,Binkai Yu,Ting Wang,Tong Wang,Hanlin Wang,Xianlin Qu,Huatong Zuo,Zhengwei Zhao,Limin Zhou,Weibo Hua,Mingzhe Chen,Hui Xia
Na4Fe3(PO4)2(P2O7) (NFPP) is currently receiving a lot of attention, as it combines the advantages of NaFePO4 and Na2FeP2O7 in terms of cost, energy density, and cycle stability. However, the issues of intrinsic poor electronic conductivity and difficult high-purity preparation may impede its practical application. Herein, the pivotal role of Cu doping in strengthening the polyanion structure and improving its electrochemical properties is comprehensively investigated. It is found that trace Cu doping not only expands the lattice volume of NFPP but also suppresses the formation of the inactive NaFePO4 impurity phase. In addition, Cu doping can effectively reduce the structural variations of NFPP during sodiation/desodiation processes (2.02%) while decreasing the band gap and lowering the ion mobility energy barrier (from 0.46 to 0.426 eV). Consequently, the Cu-doped NFPP electrode exhibits superior rate capability and long-term cycling performance. The computational simulations reveal a strong electronic interaction between Fe and Cu that tunes the electron localization and distribution, and additional Na+ transport channels can be created in NFPP by distorting the [PO4] units adjacent to the doping site, which provides a reference to enhance the performance of NFPP and reveals the great application potential of NFPP materials.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Advanced Powder Materials
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2024
·
IF 28.6
Jingjing Yan,Rundong Wu,Guoqiang Jin,Litao Jia,Gang Feng,Xili Tong
Water electrolysis via alkaline hydrogen evolution reaction (HER) is a promising approach for large-scale production of high-purity hydrogen at a low cost, utilizing renewable and clean energy. However, the sluggish kinetics derived from the high energy barrier of water dissociation impedes seriously its practical application. Herein, a series of hybrid Pt nanoclusters/Ru nanowires (Pt/Ru NWs) catalysts are demonstrated to accelerate alkaline HER. And the optimized Pt/Ru NWs (10 % wt Pt) exhibits exceptional performance with an ultralow overpotential (24 mV at 10 mA cm −2 ), a small Tafel slope (26.3 mV dec −1 ), and long-term stability, outperforming the benchmark commercial Pt/C-JM-20 % wt catalyst. This amazing performance also occurred in the alkaline anion-exchange membrane water electrolysis devices, where it delivered a cell voltage of about 1.9 V at 1 A cm −2 and an outstanding stability (more than 100 h). The calculations have revealed such a superior performance exhibited by Pt/Ru NWs stems from the formed heterointerfaces, which significantly reduce the energy barrier of the decisive rate step of water dissociation via cooperative-action between Pt cluster and Ru substance. This work provides valuable perspectives for designing advanced materials toward alkaline HER and beyond.
研究领域:
材料科学
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催化化学
·
可再生能源
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产品关联
DOI
高影响因子
ChemSusChem
·
2022
·Vol. 15
·期 11
·e202200297
·
IF 9.14
Panfeng Wu,Tianyu Wang,Qi Xue,Mengkai Wang,Ruihua Zhong,Jun Hu,Zhong Chen,Danjun Wang,Ganglin Xue
Graphical Dual active sites : Ti is introduced into the δ-Bi 2 O 3 lattice (Ti−Bi 2 O 3 ) to tune its local electronic structure. The interaction of nitrogen and the bridging oxygen in Ti−Bi local lattice realizes the activation of nitrogen, and the Ti−Bi dual active sites reduce the hydrogenated energy barrier (*NN→*NNH) from 2.65 to 2.13 eV; thus, the ammonia production rate reaches 508.6 μmol g cat −1 h −1 without sacrificial agent. Under mild conditions, nitrogen undergoes the associative pathways to be reduced with solar energy as the driving force for fixation, avoiding the high energy consumption when undergoing dissociation. Nevertheless, this process is hindered by the high hydrogenation energy barrier. Herein, Ti was introduced as hard acid into the δ-Bi 2 O 3 (Ti−Bi 2 O 3 ) lattice to tune its local electronic structure and optimize its photo-electrochemistry performance (reduced bandgap, increased conduction band maximum, and extended carrier lifetime). Heterokaryotic Ti−Bi dual-active sites in Ti−Bi 2 O 3 created a novel adsorption geometry of O−N 2 interaction proved by density functional theory calculation and N 2 temperature-programmed desorption. The synergistic effect of dual-active sites reduced the energy barrier of hydrogenation from 2.65 (Bi 2 O 3 ) to 2.13 eV (Ti−Bi 2 O 3 ), thanks to the highly overlapping orbitals with N 2 . Results showed that 10 % Ti-doped Bi 2 O 3 exhibited an excellent ammonia production rate of 508.6 μmol g cat −1 h −1 in water and without sacrificial agent, which is 4.4 times higher than that of Bi 2 O 3 . In this work, bridging oxygen activation and synergistic hydrogenation for nitrogen with Ti−Bi dual active sites may unveil a corner of the hidden nitrogen reduction reaction mechanism and serves as a distinctive strategy for the design of nitrogen fixation photocatalysts.
研究领域:
材料科学
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环境科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Nano Materials
·
2023
·
IF 5.9
Yi Jiang,Yile Dai,Xianfei Xie,Qing Wang,Jianfeng Dai
In this work, we propose a strategy that is different from the traditional technology of increasing the specific area of the TiO2 film to improve the carrying capacity of QDs in QDSSCs. Transparent anatase TiO2 films are prepared by improving the optical transmittance of the photoanode TiO2 film so that the attached QDs can capture more photons and improve the efficiency of utilizing QDs. This QDSSC preparation technology sacrifices part of QDs loading but improves the utilization efficiency of QDs. At the same time, the transparent bulk TiO2 film decreases the transmission distance of photogenerated charge carriers, reduces the cross-interface transport, optimizes the transmission path, and reduces the carrier capture composite rate compared with the TiO2 particle film. Therefore, it not only increases the Voc, FF, and PCE of QDSSCs to 0.628 V, 54.7, and 6.166%, respectively, but also has greater transparency. It meets the demand for solar cell transparency in practical applications and has a wider range of applications and better aesthetics. The mechanism simulation and theoretical analysis of photothermal conversion and electromagnetic mechanism show that the barrier of carrier transfer in bulk transparent anatase TiO2 is lower than the physical barrier between anatase TiO2 NPs. The advantages of the anatase transparent TiO2 film in the process of photogenerated charge carrier transmission are verified. It provides an idea for the development of QDSSCs. It also brings the technology of transparent TiO2 film to related fields.
研究领域:
材料科学
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光伏技术
·
界面物理
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产品关联
DOI
高影响因子
ACTA PHYSICO-CHIMICA SINICA
·
2024
·
IF 10.8
Wenxiu Yang,Jinfeng Zhang,Quanlong Xu,Yun Yang,Lijie Zhang
Covalent organic frameworks (COFs) represent a kind of novel crystalline porous organic substances with extended π -conjugation framework and tunable structures, which display great promise in photocatalysis. However, unadorned COFs suffer from sluggish reaction kinetics, and a cocatalyst is essentially needed to reduce the activation barrier toward specific surface reaction and accelerate reaction kinetics. In this work, bimetallic alloys serving as co-catalysts were decorated on COFs to enhance the photocatalytic hydrogen evolution performance. By precisely-tuning the ratio of AuCu alloy, the resultant Au 1 Cu 5 /COF-TpPa displays the highest photocatalytic hydrogen generation rate (8.24 mmol∙g −1 ∙h −1 ), even surpassing the Pt modified COF-TpPa (6.51 mmol∙h −1 ∙g −1 ). According to the systematic characterizations and theoretical calculation, Au 1 Cu 5 /COF-TpPa exhibits the significantly enhanced charge carrier separation efficiency and reduced H* formation energy barrier, thus possessing high photocatalytic performance. This work affords a valuable approach to advancing COF-based photocatalysts by employing bimetallic alloy cocatalysts. Download: Download high-res image (117KB) Download: Download full-size image
研究领域:
材料科学
·
光催化
✓ 已验证
产品关联
DOI
高影响因子
EUROPEAN POLYMER JOURNAL
·
2024
·
IF 5.8
Tianfeng Zhou,Haotian Duan,Beibei Li,Yuxia Pang,Hongming Lou,Dongjie Yang,Xueqing Qiu
The synthesis and performance optimization of solid polycarboxylate superplasticizers (PCEs) present significant challenges. In our study, a rapid synthesis of a solid polycarboxylate superplasticizer (IPCE10) was achieved using photoinitiated free radical polymerization. IPCE10 exhibited good dispersibility and improved compressive strength in concrete. Dynamic light scattering tests and molecular dynamics simulations demonstrated that the adsorption conformation of IPCE10 on the calcium silicate hydrate surface was relatively dispersed, with a thicker adsorption layer. This indicates that IPCE10 has stronger steric hindrance, resulting in superior dispersibility. Additionally, density functional theory calculations of the reaction energy barriers for radical generation by photoinitiated and azo-initiated monomers revealed that the energy barrier in the photoinitiated system was significantly lower than that in the azo-initiated system, indicating that photoinitiated polymerization is more feasible. This study proposes a simple and rapid method for the preparation of solid polycarboxylate superplasticizers, providing valuable insights for the development of high-value-added construction materials.
研究领域:
建筑材料化学
·
高分子化学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）