CHEMICAL ENGINEERING JOURNAL
·
2013
·
IF 3.473
Bo Yang,Yunfei Zhang,Shubo Deng,Gang Yu,Yonghong Lu,Jinhua Wu,Jianzhong Xiao,Gang Chen,Xiaobing Cheng,Lili Shi
The Pd/Al nanoparticles (NPs) prepared by aqueous cementation were employed to probe hydrodechlorination (HDC) efficiencies of 4-chlorophenol (4-CP) in aqueous solution and 2-chlorobiphenyl (2-PCB) in surfactant solution. Major factors affecting HDC performance were investigated including acidic types, pH conditions, and surfactant types and their concentrations. Among HCl, H 2 SO 4 , H 3 PO 4 , formic acid, and acetic acid, only HCl was the proper pH adjustor to initiate HDC reaction of 4-CP with Pd/Al NPs at pH 3.0 due to the particular penetration function of active Cl − on the compact oxide film of Al. Aqueous pH states obviously influenced HDC efficiency and its values stable at pH 3–4 were the optimum range for HDC with HCl adjustor. 0.389 mM of 4-CP could be almost completely dechlorinated into phenol after 30-min reaction using 2 g/L of Pd/Al NPs with 1.2 wt.% of Pd loading. In addition, the effect of surfactants on HDC process of highly hydrophobic 2-PCB was explored, which were employed for its better solubilization. The addition of surfactants including SDS, CTAB, Tween 80, or Brij 30 had adverse effect on HDC activity of Pd/Al NPs due to their inhibiting effect on Al corrosion. The adverse effect was closely related with the concentrations of surfactants especially for each CMC level and molecular structures.
研究领域:
环境化学
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纳米修复
·
水处理
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催化
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污染物降解
✓ 已验证
DOI
高影响因子
Journal of Physical Chemistry C
·
2021
·
IF 4.126
Yifan Li,Le Lin,Lijun Gao,Rentao Mu,Qiang Fu,Xinhe Bao
Oxygen vacancies (Vos) play a vital role in the physical and chemical properties of oxide materials and their applications. Because Vos are first produced on oxide surfaces, it has been often recognized that they are richer at the top surface than at the subsurface or bulk region. Here the depth distribution of Vos in reduced manganese oxide (MnOx) films has been studied by a combination of ion-sputtering treatment and variable-angle X-ray photoelectron spectroscopy measurement. The density of Vos on the top surface is determined to be ∼8% lower than that in the subsurface region after reduction treatment of the oxide in CO at 573 K. Density functional theory calculations show that lattice oxygen atoms in the bulk tend to migrate and fill into the Vos on the top surface with a barrier of 0.94 eV at most. The stability of Vos in the bulk is higher than that on the surface via a reduced Mn3O4 skeleton, which can be reflected by the energy of oxygen filling at the Vo.
研究领域:
材料科学
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表面化学
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催化
·
固态物理
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计算材料科学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2019
·
IF 8.456
Xue Zhao,Changjun Xiang,Fulin Zhang,Fengze Yao,Ruiqing Sheng,Qiong Ding,Wenjing Liu,Haibo Zhang,Xiaohai Zhou
The increasing global demands for eco-friendly and low-cost catalysts have propelled the advent of nanosized non-noble-metal catalysts to replace traditional noble metals. In this work, ultrafine NiO nanoparticles were prepared rapidly in situ by the strategy of transforming three-dimensional (3D) metal boron organic polymers (BOPs@Ni2+) to one-dimensional (1D) boron organic polymers (BOPs@Ni) nanorod arrays at room temperature. The 3D BOPs@Ni2+ can be quickly obtained by the interaction of 4,4′-bipyridine with Ni2+ and dodecaborate (B12H122–) in an aqueous solution. When Ni2+ is converted into NiO in situ, 1D BOPs@Ni nanostructure transformation from the 3D BOPs@Ni2+ framework was achieved due to the B–H···π interaction between B12H122– and 4,4′-bipyridine. Furthermore, BOPs@Ni exhibits high catalytic activity and rapid kinetics in the conversion of 4-nitrophenol to 4-aminophenol, and the high stability of 1D nanorod arrays guarantees the catalytic activity of BOP@Ni to barely change under recycling for at least 10 times. BOPs@Ni also exhibits good catalytic performance and high selectivity characteristics in the catalytic reduction of a series of nitrobenzene derivatives. This strategy of using BOPs@Ni2+ for loading self-supporting nanometal not only exhibits a highly efficient catalytic hydrogenation of nitrobenzene and its derivative but also provides an effective technical route for designing self-supported nanometal materials.
研究领域:
材料化学
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纳米技术
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催化
·
绿色化学
·
高分子科学
✓ 已验证
DOI
高影响因子
ENERGY CONVERSION AND MANAGEMENT
·
2019
·
IF 7.181
Zhong Ma,Shuai Zhang,Rui Xiao
The Fe 2 O 3 -Al 2 O 3 oxygen carrier is regarded to a promising candidate for chemical looping combustion (CLC). However, Fe 2 O 3 -Al 2 O 3 oxygen carrier was often subjected to a decrease of oxygen carrying capacity. The deactivation mechanism of Fe 2 O 3 -Al 2 O 3 oxygen carrier in chemical looping combustion was investigated over consecutive 20 cycles. The Fe 2 O 3 -Al 2 O 3 oxygen carrier exhibited relatively poor redox stability in a fixed bed reactor. The physico-chemical properties of cycled Fe 2 O 3 -Al 2 O 3 oxygen carrier were characterized by different characterization methods. No carbon deposit was detected in the reduction process, indicating that carbon deposition was not the cause for Fe 2 O 3 -Al 2 O 3 oxygen carrier deactivation under this experimental condition. The characterization results showed that the deactivation of Fe 2 O 3 -Al 2 O 3 oxygen carrier in redox cycles was mainly attributed to thermal sintering. The cycled Fe 2 O 3 -Al 2 O 3 oxygen carrier showed lower surface area, lower reducibility and oxygen mobility than that of fresh sample. After a certain number of redox cycles, Fe diffusion and enrichment at the surface of cycled oxygen carrier was observed. The surface Fe is unstable under high reaction temperature, leading to accelerate thermal sintering. A deactivation mechanism of Fe 2 O 3 -Al 2 O 3 oxygen carrier in CLC was proposed based on the Fe diffusion and surface sintering.
研究领域:
化学工程
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能源技术
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材料科学
·
催化
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2017
·
IF 7.504
Lu-Nan Zhang,Si-Heng Li,Hua-Qiao Tan,Shifa Ullah Khan,Yuan-Yuan Ma,Hong-Ying Zang,Yong-Hui Wang,Yang-Guang Li
During the exploration of highly efficient noble-metal-free electrocatalysts for the hydrogen evolution reaction (HER), a promising and challenging strategy is to fabricate composite nanocatalysts by finely tuning metal and/or nonmetal element components. Herein, we report a new HER electrocatalyst, which is composed of molybdenum phosphide and molybdenum carbide composite nanoparticles (NPs) coated by few-layer N-doped graphitic carbon shells (denoted as MoP/Mo2C@C). Such a new combination mode of electrocatalysts is realized by a one-step annealing route with the mixture of a Mo/P-based polyoxometalate (POM) and dicyandiamide. On the basis of this method, the simultaneous phosphorization and carbonization in a nanoscale confined space can be easily achieved by the use of POM as the molecular-element-regulating platform. MoP/Mo2C@C exhibits more remarkable HER performance over the whole pH range than those of MoP, Mo2C, and the physical mixture of MoP and Mo2C. The low overpotentials of 89, 136, and 75 mV were obtained at a current density of 10 mA cm–2 in the media of pH = 0, 7, and 14, respectively. Furthermore, MoP/Mo2C@C shows a long-term durability for 14 h over the entire pH range (0–14). Because of the protection of carbon shells, such composite electrocatalyst also possesses better transition-metal tolerance exemplified by Fe2+, Co2+, and Ni2+ than that of 20% commercial Pt/C. This work demonstrates the advantage of POM precursors in adjusting the component and properties of nanoscale composite electrocatalysts for HER, which may suggest new options for the fabrication of highly efficient composite electrocatalysts.
研究领域:
电化学
·
材料科学
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催化
·
能量转换
·
纳米材料
✓ 已验证
DOI
高影响因子
International Journal of Electrochemical Science
·
2023
·Vol. 11
·期 1
·498-505
·
IF 1.5
Jian Lu,Jianling Li,Zhixun Zhu,Yuguang Zhao,Cheng Chen,Feiyu Kang
Porous Co 3 Mo 3 N nanorods were prepared by hydrothermal process combined with ammonia annealing and applied as catalyst in Li-O 2 battery cell. The battery with the porous Co 3 Mo 3 N nanorods showed a higher initial discharge capacity of 7902.8 mAh/g c at current density of 100 mAh/g c than that with the pure Ketjen black. Moreover, the Co 3 Mo 3 N-based electrode displayed lower overpotential and better cycling performance than that of the carbon-only cathode. Such performance can be associated with the synergistic effects of high electrocatalytic activity and porous structure of the Co 3 Mo 3 N nanorods.
研究领域:
材料科学
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电化学
·
储能
·
纳米材料
·
催化
✓ 已验证
DOI
高影响因子
Advanced Science
·
2023
·Vol. 10
·期 21
·2301324
·
IF 15.1
Hanqing Dai,Wenqing Dai,Yuanyuan Chen,Yukun Yan,Guangzheng Zuo,Zhe Hu,Jinxin Wei,Wenjie Zhou,Wanlu Zhang,Wei Wei,Guoqi Zhang,Ruiqian Guo
Sulfide minerals hold significant importance in both fundamental science and industrial advancement. However, certain natural sulfide minerals, such as NaFe 3 S 5 ·2H 2 O (NFS), pose great challenges for exploitation and synthesis due to their high susceptibility to oxidation. To date, no successful precedent exists for synthesizing NFS. Here, a novel approach to synthesizing low-cost and pollution-free NFS with high stability using the high-pressure hydrothermal method based solely on knowledge of its chemical formula is presented. Moreover, an innovative strategy inspired by the cicada's molting process to develop unstable natural materials is proposed. The mechanical, thermal, optical, electrochemical, and magnetic properties of the NFS are thoroughly investigated. The storage of lithium, sodium, and potassium ions is primarily concentrated in the gap between (0 0 1) crystal planes. Additionally, as a catalyst for hydrogen evolution reaction (HER) at 10 mA cm −2 , micron-sized NFS exhibits an excellent overpotential of 6.5 mV at 90 °C, surpassing those of reported HER catalysts of similar size. This research bridges the gap in the sulfide mineral family, overcomes limitations of the high-pressure hydrothermal method, and paves the way for future synthesis of natural minerals, lunar minerals, and Martian minerals.
研究领域:
材料科学
·
无机化学
·
矿物合成
·
能源存储
·
催化
·
固态化学
·
电化学
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2020
·
IF 6.215
Xiangxi Wang,Lei Li,Zhao Wang,Zhuoyan Wu,Min Zhu,Shili Gai,Zhiliang Liu,Piaoping Yang
Boosting stability, durability, and intrinsic activity of electrocatalysts are the world’s concerns in promoting the application of oxygen evolution reaction (OER). Ni is averagely required in efficient electrocatalysts for OER, while Mo is familiar to hydrogen evolution reaction (HER). Herein, we introduce Mo into electrocatalysts for OER and synthesize an echinoids-like MoS 2 @NiS 2 electrocatalyst with unique morphology, which demonstrates rapid reaction kinetics and impressive catalysis activity. Furthermore, the electrocatalyst shows low overpotentials of 356 mV at 100 mA cm −2 as well as a Tafel slope of 82.6 mV dec −1 in alkaline media. Meanwhile, the electrocatalyst has a large double-layer capability ( C dl ) and electrochemically active surface areas (ECSA) values. The OER performances remarkably enhanced with the help of MoS 2 affiliation. Owning to the Ni compounds as the substrate, the catalyst can maintain a good stability in alkaline solution even after 10 h of chronoamperometry test at 1.51 V. Our study proposes a feasible way to obtain a high-efficient and robust OER electrocatalyst for the practical application.
研究领域:
电化学
·
材料科学
·
能量转换
·
催化
✓ 已验证
DOI
高影响因子
INORGANIC CHEMISTRY
·
2022
·
IF 5.436
Chenya Zhao,Weiyang Xu,Jie Ren,Lanshan He,Congcong Wu,Wenting Jia,Daojian Ye,Hang Zhou,Ce Hu,Ting Yu,Xingfang Luo,Cailei Yuan
Defective quantum dots (QDs) are the emerging materials for catalysis by virtue of their atomic-scale size, high monodispersity, and ultra-high specific surface area. However, the dispersed nature of QDs fundamentally prohibits the efficient charge transfer in various catalytic processes. Here, we report efficient and robust electrocatalytic oxygen evolution based on defective and highly conductive copper selenide (CuSe) QDs confined in an amorphous carbon matrix with good uniformity (average diameter 4.25 nm) and a high areal density (1.8 × 1012 cm–2). The CuSe QD-confined catalysts with abundant selenide vacancies were prepared by using a pulsed laser deposition system benefitted by high substrate temperature and ultrahigh vacuum growth conditions, as evidenced by electron paramagnetic resonance characterizations. An ultra-low charge transfer resistance (about 7 Ω) determined by electrochemical impedance spectroscopy measurement indicates the efficient charge transfer of CuSe quantum-confined catalysts, which is guaranteed by its high conductivity (with a low resistivity of 2.33 μΩ·m), as revealed by electrical transport measurements. Our work provides a universal design scheme of the dispersed QD-based composite catalysts and demonstrates the CuSe QD-confined catalysts as an efficient and robust electrocatalyst for oxygen evolution reaction.
研究领域:
材料科学
·
电化学
·
纳米技术
·
催化
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2021
·
IF 9.229
Qianru Ma,Wei Zhong,Guangyuan Du,Yuruo Qi,Shu-juan Bao,Maowen Xu,Changming Li
Room-temperature (RT) sodium–sulfur batteries hold great promise for the development of efficient, low-cost, and environmentally friendly energy storage systems. Nevertheless, the dissolution of long-chain polysulfides is a huge obstacle. In this work, a composite cathode which integrates Ni/Co bimetal nanoparticles as the catalyst and carbon spheres with abundant channels as the host is prepared for RT Na–S batteries. Moreover, a valuable strategy to reduce the dissolution of polysulfides by accurately regulating the two-step reaction kinetics of polysulfide transformation (from Na2S to long-chain polysulfides and then from polysulfides to sulfur) is presented. Through adjusting the ratio of Ni and Co, the optimal cathode with a Ni/Co ratio of 1:2 can retard the first conversion of Na2S to polysulfides and simultaneously accelerate the subsequent transformation of polysulfides to sulfur. In this case, the soluble polysulfides can immediately transform to solid sulfur as soon as it appears, thus avoiding the shuttle of polysulfides. The galvanostatic intermittent titration method and in situ Raman are employed to supervise the transformation of polysulfides during the discharge/charge process. As a result, the composite shows excellent performance as the cathode of RT liquid/quasi-solid-state Na–S batteries in terms of specific capacities, rate capability, and cycle stability.
研究领域:
储能
·
电化学
·
材料科学
·
电池技术
·
催化
✓ 已验证
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2019
·
IF 6.97
Ziqiang Wang,Kang Zheng,Songliang Liu,Zechuan Dai,You Xu,Xiaonian Li,Hongjing Wang,Liang Wang
Electrocatalytic nitrogen fixation provides a green and facile strategy for efficient synthesis of ammonia under ambient conditions, but it lacks efficient and inexpensive electrocatalysts for the nitrogen reduction reaction. Here, we report the synthesis of porous Fe2O3 nanorods grown on carbon cloth (p-Fe2O3/CC) via a surfactant-free hydrothermal reaction coupled with high-temperature calcination. The obtained p-Fe2O3/CC serves as a superior electrocatalyst for producing ammonia by electrolysis of nitrogen and water in neutral electrolytes (0.1 M Na2SO4). Benefiting from its binder-free characteristic and porous structure, p-Fe2O3/CC achieves superior catalytic performance and excellent long-term stability. This study is significant to design low-cost and binder-free porous Fe-based arrays as effective and stable electrocatalysts for electrochemical ammonia synthesis.
研究领域:
电化学
·
材料科学
·
催化
·
可持续能源
·
纳米材料
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2021
·
IF 6.901
Wenli Pei,Xiaoyang Wang,Chunhong Liu,Dong Zhao,Chun Wu,Kai Wang,Qiang Wang
Hyperbranched transition metal phosphides (TMPs) nanocrystals are an interesting class of materials, which can be used as an efficient catalyst for hydrogen evolution reaction (HER). However, big challenge remains for the preparation of ternary hyperbranched TMPs, and relationship between their HER performances and the splitting degree is also not well understood. Here, hyperbranched Co-Ni-P nanocrystals with different splitting degrees were prepared via a novel strategy, and their alkaline HER performances were studied. During the synthesis process, hyperbranched Co 2 P nanocrystals were used as template, and Ni precursors were injected into the reaction solution at different holding stage. When the Ni precursor was injected earlier, the podgy particles with low splitting degree would be obtained. Conversely, delaying the injection of Ni precursor would lead to high splitting degree. The formation process of ternary phase was also studied. After Ni precursor was injected, a Co-Ni-P amorphous layer was formed on the surface of the Co 2 P particles, and then the Ni atoms diffused into the Co 2 P phase to form Co-Ni-P nanocrystals. Electrochemical performances tests show that the splitting degree has great impact on HER performances. The higher splitting degree usually leads to larger electrochemical surface area, and higher catalytic activity can be achieved. The sheaf-like Co-Ni-P nanocrystals demonstrate a small overpotential of 119 mV at current density of 10 mA cm −2 , and good durability over 23 h in 1 M KOH solution. We believe that this work can help understand the relationship between the HER performances of hyperbranched TMPs nanocrystals and their splitting degree, and provide a synthetic strategy for the preparation of highly efficient TMPs catalysts.
研究领域:
材料科学
·
电化学
·
纳米技术
·
催化
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）