Small
·
2020
·Vol. 16
·期 13
·1906880
·
IF 11.459
Weikang Wang,Hongjian Zhou,Yanyan Liu,Shengbo Zhang,Yunxia Zhang,Guozhong Wang,Haimin Zhang,Huijun Zhao
It is an important issue that exposed active nitrogen atoms (e.g., edge or amino N atoms) in graphitic carbon nitride (g-C 3 N 4 ) could participate in ammonia (NH 3 ) synthesis during the photocatalytic nitrogen reduction reaction (NRR). Herein, the experimental results in this work demonstrate that the exposed active N atoms in g-C 3 N 4 nanosheets can indeed be hydrogenated and contribute to NH 3 synthesis during the visible-light photocatalytic NRR. However, these exposed N atoms can be firmly stabilized through forming B N C coordination by means of B-doping in g-C 3 N 4 nanosheets (BCN) with a B-doping content of 13.8 wt%. Moreover, the formed B N C coordination in g-C 3 N 4 not only effectively enhances the visible-light harvesting and suppresses the recombination of photogenerated carriers in g-C 3 N 4 , but also acts as the catalytic active site for N 2 adsorption, activation, and hydrogenation. Consequently, the as-synthesized BCN exhibits high visible-light-driven photocatalytic NRR activity, affording an NH 3 yield rate of 313.9 µmol g −1 h −1 , nearly 10 times of that for pristine g-C 3 N 4 . This work would be helpful for designing and developing high-efficiency metal-free NRR catalysts for visible-light-driven photocatalytic NH 3 synthesis.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Small
·
2021
·Vol. 17
·期 46
·2101887
·
IF 13.281
Jian Feng,Shao-hua Luo,Sheng-xue Yan,Yang Zhan,Qing Wang,Ya-hui Zhang,Xin Liu,Long-jiao Chang
Transition-metal selenides (TMSs) have emerged as prospective anode materials for sodium ion batteries (SIBs), owing to their considerable theoretical capacity and intrinsic high electronic conductivity. Whereas, TMSs still suffer from poor rate capability and inferior cycling stability induced by sluggish kinetics and severe volume changes during de/sodiation processes. Herein, a hierarchical composite consisting of a zinc-cobalt bimetallic selenide yolk and nitrogen-doped double carbon shell (denoted as Zn Co Se@NDC) is engineered and fabricated successfully. The architecture of the as-fabricated material improves the Na-ion storage performance via increasing the electron transfer kinetics, accommodating volume expansion, and mitigating the generation of by-products. As expected, the Zn Co Se@NDC electrode delivers superior sodium storage performance with long cycling stability (344.5 mAh g −1 at 5.0 A g −1 over 2000 long-term cycles) and high-rate performance (319.2 mAh g −1 at 10.0 A g −1 ). Meanwhile, the NVP@C//Zn Co Se@NDC full SIB cells are constructed successfully, retaining 96.3% of its initial capacity at 0.5A g −1 after 200 loops. The outstanding electrochemical performance and the construction of hybrid SIBs will have far-reaching influences on the development of the various rechargeable batteries.
研究领域:
材料科学
·
能源存储
✓ 已验证
DOI
PubMed
高影响因子
Advanced Energy Materials
·
2019
·Vol. 9
·期 22
·1900149
·
IF 24.884
Jiabin Wu,He Zhou,Qun Li,Ming Chen,Jun Wan,Nian Zhang,Liukang Xiong,Song Li,Bao Yu Xia,Guang Feng,Meilin Liu,Liang Huang
Atomically dispersed transition metals confined with nitrogen on a carbon support has demonstrated great electrocatalytic performance, but an extremely low concentration of metal atoms (usually below 1.5%) is necessary to avoid aggregation through sintering which limits mass activity. Here, a salt-template method to fabricate densely populated, monodispersed cobalt atoms on a nitrogen-doped graphene-like carbon support is reported, and achieving a dramatically higher site fraction of Co atoms (≈15.3%) in the catalyst and demonstrating excellent electrocatalytic activity for both the oxygen reduction reaction and oxygen evolution reaction. The atomic dispersion and high site fraction of Co provide a large electrochemically active surface area of ≈105.6 m 2 g −1 , leading to very high mass activity for ORR (≈12.164 A mg Co −1 at 0.8 V vs reversible hydrogen electrode), almost 10.5 times higher than that of the state-of-the-art benchmark Pt/C catalyst (1.156 A mg Pt −1 under similar conditions). It also demonstrates an outstanding mass activity for OER (0.278 A mg Co −1 ). The Zn-air battery based on this bifunctional catalyst exhibits high energy density of 945 Wh kg Zn −1 as well as remarkable stability. In addition, both density functional theory based simulations and experimental measurements suggest that the Co N 4 sites on the carbon matrix are the most active sites for the bifunctional oxygen electrocatalytic activity.
研究领域:
材料科学
·
电化学
·
能量存储与转换
·
纳米催化
✓ 已验证
DOI
高影响因子
JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY
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2011
·Vol. 49
·期 12
·2755-2760
·
IF 3.894
Jing Xu,Yuhong Ma,Jingyi Xie,F.J. Xu,Wantai Yang
A universal photoassisted pathway to functionalize polymeric surfaces is presented by transferring the inert surface sp 3 C H bonds into reactive groups, such as SO 3 H, NH 2 , SH, and COOH. The proposed method uses acetone as photoinitiator and different phenols with a para substituent XR as the reactants. Acetone excited by UV irradiation acts as a pair of scissors cutting both the surface C H bonds of the polymer substrate and the O H bonds of phenol, leading to the formation of carbon-centered surface chain free radicals and oxygen-centered phenoxy free radicals. By coupling of these two radicals, a variety of functional X groups with an R spacer from XR species of different phenol reactants were readily bonded to the polymeric surfaces, where phenol reactants included 4-hydroxylbenzene sulfonic acid for SO 3 H, p -aminophenol and tyramine for NH 2 , 4-hydroxythiophenol for SH, and tyrosine for COOH. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
·
2024
·
IF 2.8
Boyun Gao,Huijiang Huang,Mooeez Ur Rehman,Bin Ren,Yuruo Liu,Weipeng Fan,Pengfei Li,Lizhi Zhang,Yan Xu,Yujun Zhao
BACKGROUND The synthesis of fatty amines via fatty alcohol amination offers a promising avenue for environmentally friendly production, particularly when compared with the methods employing hydrocyanic acid which often involve significant emissions. RESULT This study explores the synthesis of n-hexylamine through one-step amination of n-hexanol utilizing a series of Ru-doped Ni catalysts supported over γ-Al 2 O 3 , achieving 61% n-hexanol yield, 35% dihylamine yield and 3.5% trihylamine yield at the n-hexanol conversion of 99%. CONCLUSION The characterization results of the catalysts revealed a significant interaction between ruthenium and nickel in the bimetallic catalysts, leading to the enhanced reducibility of Ni species and improved metal dispersion. Moreover, ruthenium species were found to play an important role in the dissociation of NH 3 into NH x (x = 1, 2), thereby significantly improving the dehydrogenation process of n-hexanol at Ni sites. The synergistic effect between the two kinds of metal sites emerges as crucial factor for the boosted alcohols amination process. © 2024 Society of Chemical Industry (SCI).
研究领域:
催化化学
·
环境科学
✓ 已验证
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2017
·Vol. 27
·期 23
·1700359
·
IF 12.124
Yafei Cheng,Shunkai Lu,Fan Liao,Liangbin Liu,Yanqing Li,Mingwang Shao
High overpotentials and low efficiency are two main factors that restrict the practical application for MoS 2 , the most promising candidate for hydrogen evolution catalysis. Here, Rh MoS 2 nanocomposites, the addition of a small amount of Rh (5.2 wt%), exhibit the superior electrochemical hydrogen evolution performance with low overpotentials, small Tafel slope (24 mV dec −1 ), and long term of stability. Experimental results reveal that 5.2 wt% Rh MoS 2 nanocomposite, even exceeding the commercial 20 wt% Pt/C when the potential is less than −0.18 V, exhibits an excellent mass activity of 13.87 A mg metal −1 at −0.25 V, four times as large as that of the commercial 20 wt% Pt/C catalyst. The hydrogen yield of 5.2 wt% Rh MoS 2 nanocomposite is 26.3% larger than that of the commercial 20 wt% Pt/C at the potential of −0.25 V. The dramatically improved electrocatalytic performance of Rh MoS 2 nanocomposites may be attributed to the hydrogen spillover from Rh to MoS 2 .
研究领域:
材料科学
·
电化学
·
催化
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纳米技术
·
能量转换
✓ 已验证
DOI
高影响因子
APPLIED ORGANOMETALLIC CHEMISTRY
·
2016
·Vol. 30
·期 8
·680-683
·
IF 2.452
Lulu Wang,Minxin Yang,Xiaochong Liu,He Song,Lu Han,Wenyi Chu,Zhizhong Sun
A bidentate-chelation assistant palladium-catalyzed direct C-H cyanation of picolinamides with TMSCN is described. The reaction of various derivatives gave the corresponding cyanated products in moderate to good yields under mild conditions. In addition, the cyanated product could transform into some valuable functional groups in good yields. Copyright © 2016 John Wiley & Sons, Ltd.
研究领域:
有机化学
·
药物化学
✓ 已验证
产品关联
DOI
高影响因子
AICHE JOURNAL
·
2022
·Vol. 68
·期 9
·e17760
·
IF 4.167
Liu Yang,Pengfei Yu,Wenyuan Li,Fengliang Cao,Xin Jin,Sheng Xue,Xianglong Zhang,Tingwei Zhang,Mingbo Wu,Wenting Wu
Hydrogen peroxide (H 2 O 2 ) has been listed as one of the 100 most important chemicals in the world. However, huge amount of residual H 2 O 2 is hard to timely decomposed into O 2 and H 2 O under acidic condition, easily resulting in explosion hazard. Here, we reported a core–shell structure catalyst, that is graphene with Co N structure encapsulated Co nanoparticles. Co N graphene shell serves as the active site for the H 2 O 2 decomposition, and Co core further enhance this decomposition. Benefiting from it, the H 2 O 2 decomposition were close to 100% after 6 cycles without pH adjustment, which increased 6 orders of magnitude compared with no catalyst. At the same time, the O 2 generation reached 99.67% in 2 h with little metal leaching, and ·OH has been greatly inhibited to only 0.08%. This work can cleanly remove H 2 O 2 with little deep oxidation and protect the process of H 2 O 2 utilization to achieve a safer world.
研究领域:
材料科学
·
化学工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
Small
·
2023
·Vol. 19
·期 20
·2207480
·
IF 13.3
Yuli Tao,Zheng Liang,Jiajiu Ye,Huifen Xu,Guozhen Liu,Dmitry Aldakov,Xu Pan,Peter Reiss,Xingyou Tian
Mixed lead-tin (Pb Sn) perovskite solar cells (PSCs) possess low toxicity and adjustable bandgap for both single-junction and all-perovskite tandem solar cells. However, the performance of mixed Pb Sn PSCs still lags behind the theoretical efficiency. The uncontrollable crystallization and the resulting structural defect are important reasons. Here, the bidirectional anions gathering strategy (BAG) is reported by using Methylammonium acetate (MAAc) and Methylammonium thiocyanate (MASCN) as perovskite bulk additives, which Ac − escapes from the perovskite film top surface while SCN − gathers at the perovskite film bottom in the crystallization process. After the optoelectronic techniques, the bidirectional anions movement caused by the top-down gradient crystallization is demonstrated. The layer-by-layer crystallization can collect anions in the next layer and gather at the broader, enabling a controllable crystallization process, thus getting a high-quality perovskite film with better phase crystallinity and lower defect concentration. As a result, PSCs treated by the BAG strategy exhibit outstanding photovoltaic and electroluminescent performance with a champion efficiency of 22.14%. Additionally, it demonstrates excellent long-term stability, which retains ≈92.8% of its initial efficiency after 4000 h aging test in the N 2 glove box.
研究领域:
材料科学
·
能源技术
·
物理化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Small
·
2020
·Vol. 17
·期 27
·1907114
·
IF 11.459
Qinzhen Li,Jinsong Chai,Sha Yang,Yongbo Song,Tao Chen,Cheng Chen,Hui Zhang,Haizhu Yu,Manzhou Zhu
Thiolate-protected nanoclusters with different charge states usually show similar structure frameworks but different electronic configurations, which are proved to dramatically affect their properties such as magnetism, photoluminescence, and catalytic activity. Until now, few nanoclusters with alterable charge states have been reported and only some of them are structurally solved, limiting the in-depth studies on their interesting properties. Here, a new Au Cu alloy nanocluster [Au 18 Cu 32 (SPhCl) 36 ] 2− (HSPhCl = 4-chlorophenylthiophenol) is synthesized and structurally solved by X-ray crystallography. Interestingly, it is found that this nanocluster can be reduced to another nanocluster with a different charge state, that is, [Au 18 Cu 32 (SPhCl) 36 ] 3− . This change in charge states is clearly proved by X-ray crystallography, electrospray ionization mass spectrometry, thermogravimetric analysis, and electron paramagnetic resonance. Furthermore, several redox methods are carried out to realize the reversible interconversion between these two nanoclusters, including electrochemical redox, introduction of H 2 O 2 /NaBH 4 , and oxidation with silica under air atmosphere. This work offers new insight into the transform progress of charge states with Au Cu alloy nanoclusters which contributes to the understanding of the relationship between electronic structure and properties of nanoclusters and further development of Au Cu nanoclusters with excellent performance.
研究领域:
材料科学
·
化学
✓ 已验证
DOI
高影响因子
ADVANCED MATERIALS
·
2019
·Vol. 31
·期 49
·1906051
·
IF 25.809
Wanbing Gong,Qinglin Yuan,Chun Chen,Yang Lv,Yue Lin,Changhao Liang,Guozhong Wang,Haimin Zhang,Huijun Zhao
Selective hydrogenation of quinoline and its derivatives is an important means to produce corresponding 1,2,3,4-tetrahydroquinolines for a wide spectrum of applications. A facile and efficient “laser irradiation in liquid” technique to liberate the inaccessible highly dispersed Co N x active sites confined inside N-doped carbon nanotubes is demonstrated. The liberated Co N x sites possess generic catalytic activities toward selective hydrogenation of quinoline and its hydroxyl, methyl, and halogen substituted derivatives into corresponding 1,2,3,4-tetrahydroquinolines with almost 100% conversion efficiency and selectivity. This laser irradiation treatment approach should be widely applicable to unlock the catalytic powers of inaccessible catalytic active sites confined by other materials.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Solar RRL
·
2021
·Vol. 5
·期 12
·2100559
·
IF 8.582
Hong-Hong Zhang,Zi-Chun Zhou,Yu-Jie Dong,Li Zhang,Hong-Yan Chen,Dai-Bin Kuang
Utilizing halide perovskites for photocatalytic aromatic C( sp 3 ) H bond activation remains a great challenge due to the serious recombination of photogenerated charge carriers and slow reaction dynamics of the materials themselves. Herein, a lead-free perovskite-based hybrid of Cs 3 Sb 2 Br 9 /g-C 3 N 4 nanosheet is constructed and applied for photocatalytic aromatic C( sp 3 ) H bond activation, which shows enhanced photocatalytic performance. By introducing ultrathin g-C 3 N 4 nanosheets as the heterogeneous nucleation sites, size-reduced and well-dispersed Cs 3 Sb 2 Br 9 nanocrystals can be obtained. The as-formed close contact and high-quality heterointerface between Cs 3 Sb 2 Br 9 and g-C 3 N 4 provides pathways for fast charge transfer which is beneficial to improve the separation efficiency of photogenerated electron−hole pairs. Under visible light irradiation, the Cs 3 Sb 2 Br 9 /g-C 3 N 4 hybrid photocatalyst can effectively oxidize toluene toward benzaldehyde and benzyl alcohol with a total conversion rate of 8346.8 μmol g −1 h −1 , which is 26.6- and 6.0-fold that of pure g-C 3 N 4 and Cs 3 Sb 2 Br 9 , respectively. This work demonstrates the potential of all-inorganic lead-free halide perovskite-based heterostructures for photocatalytic organic reactions.
研究领域:
材料科学
·
化学
·
光催化
·
纳米技术
✓ 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）