ACS Applied Materials & Interfaces
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2023
·
IF 9.5
Zaiyong Yang,Zhiheng Hao,Shunxin Zhou,Peng Xie,Zengxi Wei,Shuangliang Zhao,Fuzhong Gong
Direct synthesis of hydrogen peroxide (DSHP) from H2 and O2 offers a promising alternative to the present commercial anthraquinone method, but it still faces the challenges of low H2O2 productivity, low stability of catalysts, and high risk of explosion. Herein, by loading in a microchannel reactor, the as-synthesized Pd–Sn alloy materials exhibit high catalytic activity for H2O2 production, presenting a H2O2 productivity of 3124 g kgPd–1 h–1. The doped Sn atoms on the surface of Pd not only facilitate the release of H2O2 but also effectively slow down the deactivation of catalysts. Theoretical calculations demonstrate that the Pd–Sn alloy surface has the property of antihydrogen poisoning, showing higher activity and stability than pure Pd catalysts. The deactivation mechanism of the catalyst was elucidated, and the online reactivation method was developed. In addition, we show that the long-life Pd–Sn alloy catalyst can be achieved by supplying an intermittent flow of hydrogen gas. This work provides guidance on how to prepare high performance and stable Pd–Sn alloy catalysts for the continuous and direct synthesis of H2O2.
研究领域:
化学工程
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催化科学
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材料科学
✓ 已验证
DOI
PubMed
高影响因子
ENVIRONMENTAL TECHNOLOGY
·
2022
·
IF 3.475
Zhen-xing Yang,Wen-yu Xie,Fang-fang Ye,De-hao Li
Electro-catalytic technology is a promising approach for wastewater treatment, owing to its easy operation, minimal generation of secondary pollution, small foot-print and rapid start-up. In this work, the chlorine evolution potential of the Pd-Sn modified ruthenium(Ru)-iridium(Ir) electrode was investigated for the electro-catalytic treatment of high chlorine ammonia-nitrogen wastewater. The effect of reaction conditions on the removal of ammonia-nitrogen, kinetics and apparent activation energy of ammonia-nitrogen removal were studied. The possible denitrification process of high chlorine ammonia-nitrogen wastewater was discussed. The results indicated that the chlorine evolution potential of the Pd-Sn modified Ru-Ir electrode was 1.0956 V(vs. SCE). The electro-catalytic treatment of high chlorine ammonia-nitrogen conformed to zero-order kinetic law, and the apparent activation energy of removal process was 14.089 kJ/mol. With a current was 0.5 A, the removal efficiency of ammonia-nitrogen could achieve 100% at a reaction time of 40 min. Indirect oxidation played an essential role in the electro-catalytic ammonia-nitrogen removal using the Pd-Sn modified Ru-Ir electrode. This paper demonstrated that the electro-catalytic technology was a promising approach for efficiently treating the high chlorine ammonia-nitrogen wastewater.
研究领域:
环境工程
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废水处理
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电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2022
·Vol. 29
·期 11
·15337-15346
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IF 5.19
Yang Zhen-xing,Shang Jie,Yan Guang-xu,Wang Yu-xian,Guo Shao-hui
In this paper, Pd-Sn modified Ru-Ir electrode was prepared by thermal oxidation method, and the effects of doping amount of Pd-Sn and synthesis conditions on Pd-Sn modified Ru-Ir electrode performance were studied. Linear sweep voltammetry(LSV), cyclic voltammetry(CV), and the Tafel curve were used to study the electrochemical performance of the Pd-Sn modified Ru-Ir electrode materials. The effects of the doping amount of Pd-Sn on the microstructure and valence states of Pd-Sn modified Ru-Ir electrode materials were investigated by SEM, TEM, XRD, and XPS. When the mass of Pd-Sn accounted for 1.5% of the total mass of the elements, the molar ratio of Ru-Ir was 2:1, and the molar ratio of Pd-Sn was 3:1; the LSV, CV, and the Tafel curves indicated that Pd-Sn modified Ru-Ir electrode had the lowest chlorine evolution potential (1.0640 V vs. SCE), the best CV curve coincidence, and the smallest corrosion current density (6.5 × 10 −4 A/cm 2 ), showing the best chlorine evolution performance, the best durability, and corrosion resistance; the characterization of SEM, TEM, XRD, and XPS showed that Pd-Sn was successfully doped into Ru-Ir electrode materials; the crystallinity of Pd-Sn modified Ru-Ir electrode was the highest, and the binding energy was the lowest, but the crystal form of Ru-Ir solid solution did not have changed. The optimal synthesis conditions of Pd-Sn modified Ru-Ir electrode material were as follows: Pd-Sn molar ratio was 3:1, calcination temperature was 500 ℃, calcination time was 4 h, and water was used as solvent. Pd-Sn modified Ru-Ir electrode can efficiently treat high chlorine ammonia–nitrogen wastewater, when the reaction volume was 200 mL, the initial concentration of NH 3 -N was 100 mg/L, the concentration of chloride ion was 5000 mg/L, the current was 0.75 A, and the reaction time was 40 min; the removal rate of ammonia nitrogen can reach 100%. Responsible editor: Weiming Zhang.
研究领域:
环境科学
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电化学
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材料科学
·
废水处理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2022
·Vol. 46
·期 18
·8739-8751
·
IF 3.925
Quansheng Wu,Songhua Zhou,Chengbing Fu,Jiesong Zhang,Bo Chen,Hongyan Pan,Qian Lin
For the mono-metal Pd based catalysts, the O–O bond in O2 and H2O2 is easily dissociated due to the higher energy sites of Pd, which decreases the selectivity and productivity of H2O2. To address this issue, non-noble metals M (M = Sn, Fe, Co, Ni) were doped into palladium precursors to create a series of yolk–shell structure bimetallic catalysts Pd–M@HCS (H = hollow; C = carbon; S = sphere) with Pd–M as the core and porous carbon as the shell. The results indicated that the catalyst Pd–M@HCS doped with Sn, Fe, Co, and Ni has a weak dissociation ability for O2, and both the adsorption and dissociation ability for H2 are improved. Of these catalysts, the catalyst Pd–Sn@HCS gives the best performance, which is benefited by the suitable Pd–Sn nanoparticle size and the best Pd2+/Pd0 ratio. The influence of the nPd/nSn ratio in the Pd–Sn@HCS system on catalyst performance was further explored, and the findings revealed that Pd–Sn@HCS had the best catalytic activity and stability when the nPd/nSn ratio was 2. The catalyst's H2 conversion, H2O2 selectivity, and productivity were 35%, 97%, and 3961 mmol gPd−1 h−1, respectively. After 10 cycles, the H2O2 productivity of this catalyst remained at 92.1%, which was greater than the H2O2 productivity of the typical Pd-based catalyst Pd/C, which stayed at 37% under the same conditions.
研究领域:
催化
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化学工程
·
材料科学
·
无机化学
✓ 已验证
产品关联
DOI
高影响因子