Nanomaterials
·
2021
·Vol. 11
·期 11
·2857
·
IF 5.076
Hui Wang,Qing Dong,Lu Lei,Shan Ji,Palanisamy Kannan,Palaniappan Subramanian,Amar Prasad Yadav
Structural engineering is an effective methodology for the tailoring of the quantities of active sites in nanostructured materials for fuel cell applications. In the present study, Co nanoparticles were incorporated into the network of 3D nitrogen-doped carbon tubes (Co@NCNTs) that were obtained via the molten-salt synthetic approach at 800 °C. Morphological representation reveals that the Co@NCNTs are encompassed with Co nanoparticles on the surface of the mesoporous walls of the carbon nanotubes, which offers a significant active surface area for electrochemical reactions. The CoNPs/NCNTs-1 (treated with CaCl2) nanomaterial was used as a potential candidate for the electro-oxidation of hydrazine, which improved the response of hydrazine (~8.5 mA) in 1.0 M NaOH, as compared with CoNPs/NCNTs-2 (treated without CaCl2), NCNTs, and the unmodified GCE. Furthermore, the integration of Co helps to improve the conductivity and promote the lower onset electro-oxidation potential (−0.58 V) toward the hydrazine electro-oxidation reaction. In particular, the CoNPs/NCNTs-1 catalysts showed significant catalytic activity and stability performances i.e., the i-t curves showed notable stability when compared with their initial current responses, even after 10 days, which indicates the significant durability of the catalyst materials. This work could present a new approach for the design of efficient electrode materials, which can be used as a favorable candidate for the electro-oxidation of liquid fuels in fuel cell applications.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
Catalysts
·
2022
·Vol. 12
·期 3
·273
·
IF 4.501
Zicong Zhang,Xiangli Ru,Xiaoli Yang,Zhengyu Bai,Lin Yang
In addition to C, H and O, some biomass is also rich in mineral elements. The recovery and utilization of special mineral elements is of great significance to prepare functional materials and alleviate the current energy shortage. Herein, we describe a facile strategy for making full use of the chemical composition (C, Fe) and special structure of red blood cells (RBCs) from waste pig blood to fabricate a dual metal (Fe, Co)-nitrogen (N)-doped porous carbon catalyst by pyrolysis of a mixture of RBCs biomass, cobaltous acetate, and melamine. The porous catalyst displays a comparable activity for oxygen reduction reaction (ORR) to that of commercial Pt/C catalyst, with a half-wave potential of 0.821 VvsRHEin alkaline media and 0.672 VvsRHEin acid electrolyte. Especially, the as-prepared catalyst shows excellent methanol tolerance and stability in both acidic and alkaline electrolytes, which is superior to commercial Pt/C catalysts. The excellent ORR activity of FeCo-N/C(RBC)can be ascribed to the porous morphology and the cooperation between metal and nitrogen species. This work provides a novel idea of exploiting the composition of renewable biomass to modulate the activity and stability of carbon-based ORR catalysts.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED PHYSICS
·
2022
·Vol. 132
·期 18
·
IF 2.877
Zheng Xiaochun,Ren Shoutian,Gai Qixiao,Wang Yidi,Liu Wenjun
Various defects of nanocomposites inevitably bring some harmful effects on their photoelectric performance, especially considering that interface defects seriously hinder the carrier interfacial transfer. Here, the interface optimization can be realized between graphitic carbon nitride (C 3 N 4 ) and CoP co-catalyst by the introduction of good conductive carbon nanosheets (CNs). As a result, the defect density of synthesized C 3 N 4 /CNs/CoP is reduced to 1.40 × 10 12 cm −3 from 2.55 × 10 12 cm −3 of C 3 N 4 /CoP, and its interface impedance is correspondingly reduced to 34% of that of C 3 N 4 /CoP. Therefore, the optimal H 2 evolution rate of 5.26 mmol g −1 h −1 and apparent quantum efficiency of 9.27% at 420 nm are realized, which are 4.8 and 8.1 times that of C 3 N 4 /CoP photocatalyst in the absence of CNs, respectively. This work provides a general solution to reduce defect density and carrier transfer resistance in nanocomposites by the introduction of a highly conductive buffer layer.
研究领域:
材料科学
·
光催化
·
能源科学
✓ 已验证
DOI
高影响因子
Journal of Water Process Engineering
·
2022
·
IF 7.34
Ying Wang,Haoyu Chen,Chao Chen,Zikun Zhang,Yin Xu,Guangjiao Chen,Yanlong Zhang
The anammox-HAP coupling process can simultaneously achieve high-efficiency nitrogen removal and phosphorus recovery from sewage. The composition and physical properties of the byproducts (aHAP) collected in the anammox-HAP process were analyzed. In addition, the application potential and mechanisms for Cd(II) adsorption by aHAP in wastewater were investigated. The results show that aHAP is mainly composed of hydroxyapatite and calcium carbonate , having granular structure with honeycombs and pores. The aHAP shows an adsorption capacity of 21.10–34.80 mg/g for Cd(II) removal, and the adsorption behavior is consistent with pseudo-second-order and intra-particle diffusion models, showing that the rate-limiting step is controlled by the chemical reaction of surface complexation, ion exchange, and precipitation. In addition, the remaining anammox biomass in aHAP can bind Cd(II). The aHAP also shows a pH buffer capacity when the initial pH ranges between 4.10 and 8.46, and the final pH can be stabilized in the range of 6.3 to 8.3, which is suitable for anammox reactions. Collectively, the anammox-HAP coupling process can not only be used to achieve high-efficiency nitrogen and phosphorus removal, but its aHAP byproduct shows good adsorption properties and pH buffering capacity, which meets the requirements of green chemistry and has high economic and environmental benefits.
研究领域:
环境科学
·
污水处理
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2020
·Vol. 8
·期 14
·6795-6803
·
IF 11.301
Lang Pei,Jiasong Zhong,Taozhu Li,Wangfeng Bai,Shiting Wu,Yongjun Yuan,Yifan Chen,Zhengtao Yu,Shicheng Yan,Zhigang Zou
Developing a highly efficient and low-cost oxygen-evolution-reaction (OER) electrocatalyst is an important route to overcome the rate-determining step of water splitting. Here, we directly grew a CoS2 nanoarray core with an N-doped graphitic carbon (NGC) shell on Ni foam (NF) to construct a core–shell nanorod array electrode, CoS2@NGC@NF. The CoS2 core with a high work function (∼5.5 eV) tends to capture electrons from the NGC layer (4.5–5.2 eV) to induce an electron-poor NGC shell with a significant downshift of the carbon Fermi level, facilitating the adsorption of O-containing intermediates and affording decreased activation energy during the OER process. As a result, the three-dimensional NGC encapsulated CoS2 array assembly exhibited excellent electrocatalytic OER activity with a low overpotential of 243 mV at a current density of 10 mA cm−2 and a small Tafel slope of 71 mV dec−1 in 1.0 M KOH. Our findings may suggest that manipulating the interface energetics by the work function difference is a potential route to the design of high-performance OER electrocatalysts.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
Catalysis Science & Technology
·
2021
·Vol. 11
·期 14
·4783-4792
·
IF 6.119
Yi Zhang,Shuo Gu,Xiaoyu Zhou,Kaiyue Gao,Kai Sun,Di Wu,Jingjing Xia,Xiufang Wang
Photocatalytic nitrogen fixation performance is mainly hampered by slow carrier transport and inefficient surface reaction, where surface oxygen vacancies have been proved to alleviate these limitations. However, there are a few reports on the introduction of metal vacancies into photocatalysts and the effect of metal vacancies on the N2 photofixing properties. Herein, we injected bismuth vacancies (VBi) into the surface of BiOBr nanospheres with oxygen vacancies (VO) via an ion exchange strategy to form hierarchical Bi2MoO6/BiOBr composite structures. The intentionally introduced VBi adjust the band structures of VO–BiOBr and act as charge separation centers in coordination with VO, which improves the separation efficiency of electron–hole pairs. The presence of VBi and the Bi2MoO6 phase enhances the light absorption of the composite materials. Additionally, the hierarchical nanosheet assembly structure facilitates the surface adsorption and activation of N2 on the catalyst. In particular, the optimal defect-rich Bi2MoO6/VBi+O–BiOBr exhibits the best photocatalytic ammonia production activity. After two hours, the NH3 yield was 412.18 mol L−1 without any noble metal cocatalyst and sacrificial agent, and was nearly 4 times higher than that of the original VO–BiOBr (96.08 mol L−1). This work provides a new inspiration for the design of efficient N2 immobilizing photocatalysts through synergistic metal and oxygen vacancy engineering.
研究领域:
材料科学
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环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
Materials
·
2024
·Vol. 17
·期 6
·1440
·
IF 3.1
Yarong Bai,Chuhan Miao,Weilong Ouyang,Lang Wang,Haiqiang Wang,Zhongbiao Wu
Barium and iridium supported on Zeolite Socony Mobil-5 (ZSM-5) are efficient catalysts for the selective catalytic reduction of nitric oxide by carbon monoxide (CO-SCR), with enhanced cyclic stability. The introduction of Ba hindered the oxidation of metallic Ir active species and enabled Ir to maintain an active metallic state, thereby preventing a decrease in catalytic activity in the CO-SCR reaction. Moreover, the Ba modification increased the NO adsorption of the catalyst, further improving the catalytic activity. Owing to the better anti-oxidation ability of Ir0in IrBa0.2/ZSM-5(27) than in Ir/ZSM-5(27), IrBa0.2/ZSM-5(27) showed better stability than Ir/ZSM-5(27). Considering that all samples in the present study were tested to simulate actual flue gases (such as sintering flue gas and coke oven flue gas), NH3was introduced into the reaction system to serve as an extra reductant for NOx. The NOxconversion to N2(77.1%) was substantially improved using the NH3-CO-SCR system. The proposed catalysts and reaction systems are promising alternatives for treating flue gas, which contains considerable amounts of NOxand CO in oxygen-enriched environments.
研究领域:
环境科学
·
催化化学
✓ 已验证
DOI
PubMed
高影响因子
CATALYSIS LETTERS
·
2021
·Vol. 152
·期 6
·1651-1659
·
IF 3.186
Tao Lei,Zhang Xueliang,Song Lizhu,Hu Huilin,Liu Lequan,Ye Jinhua,Wang Defa
As one of the most promising routes for production of low-carbon olefins (e.g., ethene and propene etc.), methanol-to-olefins (MTO) reaction is influenced largely by the temperature. Noble metal (e.g., Au, Ag, etc.) nanoparticles are known to exhibit the localized surface plasmon resonance (LSPR) effect, which has been applied in photothermal reactions. Owing to the increased light absorption ability in near-infrared region, titanium nitride (TiN) nanoparticles exhibit a superior LSPR effect over noble metals. Herein, we report on the MTO reaction via photothermal effect over a series of TiN(x)/SAPO-34 (x = 0.5, 0.75, 1, 2, 5, 10, 13 wt%) catalysts prepared by a simple mechanical grinding method. The MTO reaction over TiN(x)/SAPO-34 was carried out under a 300 W xenon lamp irradiation. The MTO reactivity of TiN(x)/SAPO-34 was influenced by both the photothermal temperature from the LSPR effect of TiN nanoparticles and the Brønsted acid sites on SAPO-34, both of which were dependent on the loading amount of TiN nanopartiles. The synergistic effect of high photothermal temperature, sufficient Brønsted acid sites and moderate BET surface area gave rise to the optimal catalytic performance of MTO reaction over TiN(10)/SAPO-34, which exhibited a methanol conversion of 73.1% and an ethene selectivity of 62.5%. Graphic Abstract
研究领域:
化学工程
·
材料科学
✓ 已验证
DOI
高影响因子
ChemNanoMat
·
2024
·Vol. 11
·期 1
·e202400426
·
IF 2.6
Yiting Wang,Xinran Zhao,Ruirui Cao,Jun Yang
The selection and optimization of cathode materials are crucial for enhancing the performance of aqueous zinc-ion batteries. In this work, different active materials were created by combining Sulfur powder and polydopamine in four different mass ratios. The novel N-doped carbon/WS 2 is obtained. Thanks to the optimization of the dopamine-carrying tungsten ion precursor and Sulfur powder (1 : 2, 1 : 4, 1 : 6 and 1 : 8), the four samples exhibited different morphology. The N−C/WS 2 -6-based zinc ion batteries with the highest specific capacity, 120.0 mAh/g in the first discharge at 2.0 A/g, and 78.0 mAh/g after 2500 cycles, with a capacity retention of 65 %, had a relatively good overall performance, according to the results. The reaction kinetics characteristics of the N−C/WS 2 -6 cathode reveal that diffusion has a significant impact on the processes in the aqueous zinc ionic material N−C/WS 2 -6.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
DOI
高影响因子
EES Catalysis
·
2023
·Vol. 2
·期 1
·324-334
·
IF 0
Haifan Wang,Menglei Yuan,Jingxian Zhang,Yiling Bai,Ke Zhang,Bin Li,Guangjin Zhang
Electrocatalysis has been intensively studied in nitrogen (N2) reduction for its sustainable power and stable catalytic performance, but it is still limited by weak activation of N2 at the catalytic sites, and the competition from the hydrogen evolution reaction (HER). The special d-orbital electron arrangement of transition metals and the tuning of the microenvironment provide possible strategies to enhance the activation of N2, while improving the selectivity of the eNRR. Herein, FeO(OH, S) with high spin state and Mo–FeOOH with low spin state were designed around the FeOOH-based catalysts through elemental doping, which could achieve excellent ammonia yield performance of 80.1 ± 4.0 μg h−1 mgcat−1 (FE 36.9 ± 0.5%) and 86.8 ± 4.1 μg h−1 mgcat−1 (FE 29.1 ± 0.8%) in 0.1 M LiClO4 at −0.6 V vs. RHE, respectively, coupled with polyethylene glycol (PEG) to inhibit the HER. Based on theoretical calculations to investigate the adsorption of N2 on Fe sites, the FeO(OH, S) catalyst has stronger adsorption ability, which may originate from the high spin effect, which means that the more isolated and highly active eg orbital electrons are more beneficial to realize the electronic feedback mechanism, promoting the d–π* orbital interaction with N2.
研究领域:
电化学
·
催化化学
·
材料科学
✓ 已验证
DOI
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Lin-Chao Yang,Quan Zhou,Jin-Qiu Liu,Zhuo Wang,Yue-Chan Song,Wen-Wen Wu,Peng Liu
Extensive studies on TiO 2 -based colossal permittivity (CP, dielectric constant ε’ >10 3 ) materials have focused on the cation doping of metal elements; however, little attention has been paid to nonmetallic dopants. Compared to metallic elements, nonmetallic atoms with small radii and high activities, such as H, C, B, and N, can be used as anion-doping elements. Their incorporation into the TiO 2 lattice includes interstitial and substitutional doping, which can influence the bandgap of TiO 2 and its electron transport performance differently, thereby exhibiting considerable potential in TiO 2 -based applications. In this study, different N-containing compounds (BN and NH 4 Cl) were doped into rutile TiO 2 , while homogeneous ceramics of single-phase rutile TiO 2 were prepared via solid-state sintering. The effects of co-doping N, Cl, and N, B on the dielectric properties of rutile TiO 2 ceramics were investigated. While N and Cl doping showed no considerable effect on the dielectric properties of rutile TiO 2 ceramics, the co-doping of N and B doping in rutile TiO 2 considerably increased the dielectric constant to >10 4 with suppressed tan δ in a wide frequency range from 1 kHz to 10 MHz. These ceramics exhibited excellent frequency stability (up to 100 MHz) and temperature stability (153–513 K), which outperforms most reported transition metal co-doped TiO 2 ceramics, thereby highlighting the untapped potential of the non-metallic dopants in enhancing dielectric materials.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Lin-Jiang Zhong,Shu-Jie Hu,Di Wu,Meng-Yue Zhang,Hong Liu,Yuan Liu
Both the sustainable development and environmental protection urge a demand of new paradigm to recover high-quality nutrients from source-separated urine, but the simultaneous recovery of phosphorus and nitrogen is difficult due to the complex composition. Herein, a coupled system consisting of a flow-electrode capacitive desalination and magnesium-air fuel cell (FCDI-MAFC) was proposed to accomplish electrochemical selective separation plus induced precipitation. The results showed that ionic species in urine were effectively separated from the non-ionic components to generate a urea solution with purity up to 99.7%. Ionic species were converted into artificial phosphate ores (APOs) with a phosphate content of 98.2%. The mass proportion of struvite in the APOs exceeded 90%. The energy consumption also decreased by 13% over five batches of operation. The overall results provide a novel method for the electrochemical selective separation and recovery of high-quality nutrients from complex wastewater.
研究领域:
环境科学
·
资源回收
·
电化学工程
✓ 已验证
DOI
高影响因子