CHINESE JOURNAL OF CATALYSIS
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2024
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IF 15.7
Adel Al-Salihy,Ce Liang,Abdulwahab Salah,Abdel-Basit Al-Odayni,Ziang Lu,Mengxin Chen,Qianqian Liu,Ping Xu
The potential of sustainable hydrogen production technology through water splitting necessitates the rational design of oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) bi-functional electrocatalysts . In this context, we initially synthesized and empirically evaluated ultralow Ru-doped NiMoO 4 @Ni 3 (PO 4 ) 2 core-shell nanostructures on nickel foam (Ru-NiMoO 4 @Ni 3 (PO 4 ) 2 /NF). The hydrous NiMoO 4 nanopillars were hydrothermally grown on NF, followed by successive RuCl 3 etching and subsequent phosphorylation processes, leading to the final Ru-NiMoO 4 @Ni 3 (PO 4 ) 2 /NF. The catalyst demonstrated impressive HER overpotential values of −14.8 and −57.1 mV at 10 and 100 mA cm −2 , respectively, with a Tafel slope of 35.8 mV dec −1 . For OER at 100 mA cm −2 , an overpotential of 259.7 mV was observed, with a Tafel slope of 21.6 mV dec −1 . The cell voltage required for overall water splitting was 1.43 V at 10 mA cm −2 and 1.68 V at 100 mA cm −2 . Moreover, the catalyst exhibited superior stability for 150 h, emphasizing its practical utility for long-term applications. Subsequent density functional theory calculations aligned with these empirical findings, indicating a low water dissociation energy barrier (Δ G b = 0.46 eV), near-zero free adsorption energy for HER (Δ G *H = 0.02 eV), and suitable free adsorption energy for OER (Δ G *OOH − Δ G *OH = 2.74 eV), alongside a high density of states near the Fermi level . These results, informed by both experimental evaluation and theoretical validation, highlight the potential of Ru-NiMoO 4 @Ni 3 (PO 4 ) 2 /NF as a high-performance catalyst for water splitting, setting a solid foundation for advancements in sustainable energy technologies.
研究领域:
材料科学
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催化化学
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可再生能源技术
✓ 已验证
产品关联
DOI
高影响因子
GREEN CHEMISTRY
·
2021
·Vol. 23
·期 3
·1353-1360
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IF 10.182
Xiaodong Liu,Xiaohao Liu,Ning Li,Peiyong Ma,Ying Zhang
Direct and selective conversion of renewable lignocellulose to the platform molecule sorbitol is attractive for valorization of biomass. Herein, a series of phosphate solid acids were prepared and loaded with Ni for cellulose conversion to produce high value-added sorbitol. Zirconium phosphate (ZrP) exhibited the best catalytic activity among the screened catalysts. To explore the structure–function relationship for sorbitol production, systematic characterization studies including XRD, TEM, AAS, HADDF-STEM-EDS, XPS, FT-IR, NH3-TPD, and H2-TPD and comparative experiments were carried out. It was found that the precise regulation of the acid site and the hydrogenation site of the catalyst was crucial to inhibit humin formation and improve the yield of sorbitol. Using Ni/ZrP2 as the catalyst, 60.8% yield of sorbitol was achieved when microcrystalline cellulose (MCC) was used as the substrate. Moreover, 40.2% yield of sorbitol and 67.9% yield of xylitol were obtained directly from birch wood.
研究领域:
催化化学
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生物质转化
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可再生资源利用
✓ 已验证
产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2020
·Vol. 44
·期 17
·6810-6817
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IF 3.288
Yanchao Xu,Shanshan Xiong,Shuting Weng,Juan Wang,Jing Wang,Hongjun Lin,Yang Jiao,Jianrong Chen
N-Doped carbon-incorporated Ni2P/Ni was reasonably designed and synthesized from nickel-based metal organic framework (Ni-MOF) precursors via a novel simultaneous carbonization and phosphatization process. Interestingly, subtle phosphating significantly improves the energy storage performance of supercapacitors (SCs). Ni2P/Ni/C composites exhibit a good energy storage performance with a specific capacitance of 257.2 C g−1 at 1 A g−1. The corresponding hybrid supercapacitor achieves an energy density of 25.4 W h kg−1 at a power density of 750 W kg−1, ultrahigh electrochemical cyclic stability (98.2% retention after 4000 cycles) and nearly 100% coulombic efficiency with a Ni2P/Ni/C-100 positive electrode and a porous carbon negative electrode, respectively. These can be attributed to the synergetic effects of N-doped carbon and metal phosphates, which ensure good electrical conductivity and provide rich reactive sites as well as stable architecture. These results indicate that the controlled pyrolysis of MOFs is an effective method to design a kind of high-performance electrode material for hybrid supercapacitors.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·Vol. 50
·期 14
·24995-25004
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IF 5.1
Zhiyi Li,Haili Sun,Wei Wei,Fengxia Liu,Xiaofei Xu,Zhijun Liu
The emerging market of high-power lithium-ion batteries (LIBs) highlights the importance of developing high-voltage cathodes. Lithium nickel phosphate (LiNiPO 4 ) with the highest theoretical discharge potential (∼5.1V) has attracted increasing attention due to its stable olivine structure. In this study, ultrathin carbon layer-coated LiNiPO 4 was synthesized using oleylamine-assisted solvothermal method under different solvothermal times, and the effect of solvothermal time (1h–18h) on LiNiPO 4 samples is fully investigated. X-ray diffraction (XRD) shows that high-purity LiNiPO 4 materials can be prepared after calcination of the solvothermal product under N 2 , but adding part of H 2 to the calcination atmosphere will lead to the generation of impurities in the target product. As the solvothermal time increases, the product will agglomerate and grow, the particle size will increase, and the morphology will change from nanoparticle to rodlike structure. After the high-temperature calcination step, the oleylamine is completely carbonized, and a conductive carbon layer is successfully coated on the LiNiPO 4 with the thickness of 2 nm. As the solvothermal time increases, the graphitization degree of oleylamine increases after carbonization. The existence of the carbon layer and the increase in the degree of graphitization are beneficial to improving the electrical conductivity and Li-ion diffusion rate of LiNiPO 4 . The initial discharge capacity of LNP@C-12h product prepared with 12 h solvothermal time is 35 mA h g −1 at 0.1 C. Rietveld analysis shows that the anti-site defect concentration of the LNP@C material is 1.07 %, and the proportion increases to 2.83 % after several cycles. This work provides a positive contribution to the synthesis and modification of high-voltage LiNiPO 4 materials and explains the electrochemical performance degradation of LiNiPO 4 from the perspective of increasing the concentration of anti-site defects.
研究领域:
材料科学
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电化学
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纳米科技
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能源存储
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锂离子电池
✓ 已验证
DOI
高影响因子