INORGANIC CHEMISTRY
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2025
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IF 4.7
Xi Zhou,Yu Cheng,Xinnan Xu,Lifang Zhang,Shu Tian,Xiaohui Xu,Baocong Guo,Weidong Tang,Chenglin Yan,Tao Qian
The hydrogen production technology of water splitting under a high current density is the key to solve the efficient utilization of hydrogen energy. However, it is difficult for existing catalysts to exhibit bifunctional high-current activity in the same electrolyzer, considering that the bimetallic site can endow the catalytic material asymmetry and heterogeneity and then change the intrinsic electronic structure. Herein, we constructed a La–Fe dual-site coupled self-assembled membrane electrode (D-LaFe-SAME), and the introduction of the dual site reduced the Bader charge value of the La site from 0.87 to 0.83|e|, while the Bader charge of the Fe site increased from 0.69 to 0.70|e|, thus optimizing the Bader charge value of La–Fe active sites to a close equilibrium. Consequently, the free energy barrier of the rate-determining step is optimized, and the catalytic activity is greatly improved. Prominently, the optimal D-LaFe-SAME can achieve current densities of up to 2000 mA cm–2 at very low overpotentials (−640 mV for HER and 626 mV for OER), which is even better than the commercial precious metals Pt/C and IrO2. Surprisingly, when we use a large area of D-LaFe-SAME for overall water splitting, it can operate stably at currents up to 4 A. The dual-site coupled strategy based on the Bader charge balance mechanism proposed in this work is crucial for the construction of an efficient and high-current electrocatalytic system for hydrogen production in the same electrolyzer and plays a key role in achieving the goals of carbon neutrality.
研究领域:
能源科学
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催化
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材料科学
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电化学
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纳米技术
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产品关联
DOI
PubMed
高影响因子
FUEL PROCESSING TECHNOLOGY
·
2025
·
IF 7.7
Peng Gan,Kai Zhang,Jingli Yang,Baobin Wang,Guihua Yang,Chengcheng Qiao,Lei Zhang,Jiachuan Chen
The application of biorefinery technologies to convert xylo-oligosaccharide (XOS) from pulping process into biofuels or high-value chemicals holds significant potential for extending the value chain of the pulp and paper industry, while simultaneously promoting sustainability. In this study, a series of dual-acid functionalized covalent organic frameworks (COFs) were synthesized to catalyze the one-step liquid-phase conversion of XOS into furfural. The results indicated that TAPT-DHPA exhibited exceptional catalytic activity, achieving a furfural yield of 78.6 % at 180 °C for 3 h with 0.16 wt% catalyst. Furthermore, TAPT-DHPA demonstrated excellent stability, maintaining a furfural yield above 77 % after six reuse cycles. Bader charge analysis via VASP software revealed the presence of both Brønsted and Lewis acid active sites in TAPT-DHPA, arising from the ionization of hydrogen in phenolic hydroxyl groups and the strong electron-withdrawing nature of the triazine ring, respectively. These characteristics are key factors in TAPT-DHPA's superior catalytic performance. Density functional theory calculations confirmed that the most favorable pathway for furfural production involves a cyclic anhydride intermediate, with the rate-limiting step being the initial dehydration of D-xylose triggered by proton attack on the 2-OH group. The addition of TAPT-DHPA reduced the activation energy of this rate-limiting step by 54.43 %.
研究领域:
化学工程
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材料科学
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催化
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绿色化学
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生物炼制技术
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产品关联
DOI
高影响因子
Journal of Physical Chemistry Letters
·
2025
·
IF 4.6
Weidong Tang,Xiaohui Xu,Yu Cheng,Baocong Guo,Xinnan Xu,Chunlin Mu,Yinshi Huang,Xi Zhou,Chenglin Yan,Tao Qian
The efficient development of electrocatalysts for ammonia oxidation anodes represents a critical challenge which hinders the commercialization of direct ammonia fuel cells (DAFCs) and the realization of energy transition goals. Platinum (Pt)-based catalysts play a key role in ammonia oxidation reactions (AOR); however, their reaction kinetics are sluggish at low temperatures and are susceptible to toxicity from intermediate species such as *N, which limits their applicability at ampere-level currents. Drawing inspiration from the “stepwise dehydrogenation mechanism” and the concept of “Bader charge”, we have designed a hypo-electronegativity atom mediated Pt-based high-entropy alloy regulation strategy. This approach exploits the electronegativity difference between Zn and Pt to induce the enrichment of Bader charges on the Pt atom surface, thereby enhancing the adsorption properties of Pt atoms and lowering the reaction energy barriers during the AOR process. Consequently, the appropriately Zn-mediated Pt-based high-entropy alloy achieves a peak current density of 351.5 A gPt–1 at ambient temperature (25 °C), which is 2.5 times higher than that of commercial Pt/C under comparable conditions. Notably, a peak power density of 4.67 mW cm–2 can be achieved at 25 °C for a low-temperature DAFC using the Pt-6HEAs-Zn18 as the anode catalyst. The Zn-mediated Pt-based high-entropy alloy strategy we designed provides valuable insights for the development of other efficient AOR catalysts that can achieve ampere-level current densities.
研究领域:
电化学
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催化
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材料科学
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能量转换
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表面科学
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产品关联
DOI
PubMed
高影响因子
ACS Applied Energy Materials
·
2025
·
IF 5.5
Yu Shao,Zhisheng Mao,Jiarui Wang,Xianfeng Hao,Yongchao Jia,Yuanhui Xu,Keju Sun
The electrochemical synthesis of hydrogen peroxide through two-electron oxygen reduction (2e– ORR) presents a sustainable alternative to conventional synthesis methods, such as the anthraquinone method. TiO2-based materials are promising candidates due to their stability and tunable electronic properties, but their intrinsic 2e– ORR activity and selectivity are insufficient for practical applications. Here, we report that strategic Fe doping significantly enhances the 2e– ORR performance of TiO2. The optimized Fe-TiO2 catalyst exhibits remarkable activity and selectivity, achieving a 30% increase in H2O2 selectivity (from 47% to 77%) while reducing the electron transfer number from 3.05 to 2.45 in 0.1 M KOH electrolyte. Notably, the material shows substantially improved electrochemical active surface area (ECSA) and ORR kinetics, culminating in an exceptional H2O2 production rate of 406 mmol·gcat–1·h–1 with 97.5% Faraday efficiency at 0 V vs RHE in an H-cell configuration. Density functional theory (DFT) calculations reveal the mechanistic origins of this enhancement: Fe doping effectively narrows the band gap and lowers the oxygen vacancy formation energy, thereby boosting electrical conductivity as confirmed by experimental characterization; and the modified electronic structure increases Bader charge accumulation on the terminal oxygen of adsorbed *OOH intermediates, facilitating protonation at this site and consequently promoting the 2e– pathway. These dual effects synergistically enhance both ORR activity and H2O2 selectivity. This study not only presents Fe-TiO2 as an efficient, earth-abundant catalyst for sustainable H2O2 production but also establishes fundamental design principles for developing advanced metal oxide electrocatalysts through targeted heteroatom doping.
研究领域:
电化学
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材料科学
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催化
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环境化学
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理论化学
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产品关联
DOI
高影响因子
Laser & Photonics Reviews
·
2023
·
IF 11
Chunli Zhao,Yuan Gao,Jing Wang,Jianbei Qiu
Lead-free rare-earth-based perovskites have received widespread attention for their unique optical properties, although achieving efficient broadband near-infrared (NIR) emission with these materials remains a challenge. Here the synthesis of a rare earth-based double perovskite (Cs 2 NaScCl 6 ) by an improved solid phase method is reported. The doping of Cr 3+ led to the formation of [CrCl 6 ] 3− octahedron, which exhibited a broadband NIR emission peaked at 950 nm and a half-peak width of 162 nm. It is worth noting that with the same actual Cr 3+ content, the luminous intensity of Cs 2 NaScCl 6 synthesized by the improved solid-phase synthesis is four times higher than the product synthesized by the hydrothermal method. an efficient Cl − -Cr 3+ charge transfer sensitization facilitated by localized electrons in [CrCl 6 ] 3− octahedron is the mechanism for the strong NIR emission of Cr 3+ is proposed. Calculations based on density functional theory and Bader charge analysis support the notion that electrons in [CrCl 6 ] 3− octahedrons are strongly localized in Cs 2 NaScCl 6 :Cr 3+ , which is conducive to the Cl − –Cr 3+ charge transfer process, resulting the internal quantum efficiency of 100% and external quantum yield as 42.3%. The highly efficient ultra-broadband NIR emission with excellent stability offers many opportunities for applications in the field of NIR night vision and bio-imaging.
研究领域:
材料科学
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光学
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纳米技术
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光子学
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产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
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2023
·Vol. 34
·期 24
·1-17
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IF 2.8
Fan Yan,Wang Lei,Sun Xueqin,Li Cuili,Liu Jiacheng
A series of UiO-66-NH 2 -CA-Cu/g-C 3 N 4 (UCC 1 /CN x ) heterogeneous photocatalysts were constructed via a facile physical mixing treatment of the covalently post-modified MOF (UiO-66-NH 2 -CA-Cu) and functional materials g-C 3 N 4 . The tetracycline removal by the photocatalysis coupled with persulfate activation were studied under white light irradiation. The optimal UCC 1 /CN 20 photocatalyst showed the best photocatalytic performance, in which 94.0% TC could be efficiently eliminated ( k = 0.08669 min −1 ) within 30 min. The satisfactory degradation performance could be ascribed to the effective separation of photogenerated electron-hole pairs over the heterogeneous binary structure, which were demonstrated by several characteristic technologies including photoluminescence spectra, electrochemical impedance spectroscopy, transient photocurrent response and Bader charge analysis based on density functional theory calculations. Moreover, a possible mechanism behind the photocatalytic degradation was proposed and further affirmed by the quenching experiments and electron spin resonance measurements. Our work may supply a feasible idea for treating wastewater contained organic pollutants based on the heterogeneous photocatalyst.
研究领域:
环境科学
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材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
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