成果筛选
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筛选条件 : Tao HU
Li Tian; Tao Hu; Yawen Guo; Peng Ju; Xiujuan Chen; Yueming Li
Journal of Colloid and Interface Science, 2025 679 - EI SCIE

摘要 : The design of self-supporting structure is particularly important to improve the stability and electrochemical performance of hydrogen evolution reaction electrode. Here, a facile strategy for building novel ultra-stable 0D-2D-3D integrated self-supporting electrode with high conductivity, sufficient diffusion channels and large reactive surface area was proposed. In the heterostructure, 2D Ti 3 C 2 T x flakes in-situ synthesized on 3D network porous Ti 3 AlC 2 surface which provides the multiple reactive surface areas and aggregation resistance to facilitating 0D ultrafine Pt nanoparticles uniform anchorage. Combined with structural characterization and first-principles calculations revealed that, the highly dispersed ultrafine Pt synergistically coupling strong metal-support interactions creates a unique multifunctional catalytic interface with high stability and atomic utilization efficiency of Pt to promote the HER in acidic and seawater. The resultant self-supporting electrode (support 0.48 wt% Pt) exhibits much superior activity to 10 % commercial Pt/C (loaded on foam nickel) in 0.5 M H 2 SO 4 (55 mV@10 mA cm −2 ) and simulate seawater (196 mV@10 mA cm −2 ) while reducing the Pt usage by 15 times. Meanwhile, the electrode also illustrates outstanding stability under high current densities (100 h@100 mA cm −2 ). This study provides a new design idea for developing integrated self-supporting catalytic electrodes to meet the durability of hydrogen evolution reaction applications in harsh environments.

Changhong Wang; Zhengyang Liu; Quanxiao Peng; Dandan Xing; Tao Hu; Feng Du
Angewandte Chemie, 2025 137 (3)

摘要 : Electrochemical reduction of nitrate to ammonia (NRA) offers a sustainable approach for NH3 production and NO3− removal but suffers from low NH3 yield rate (<1.20 mmol h−1 cm−2). We present bimetallic Cu11Ag3 nanotips with tailored local environment, which achieve an ultrahigh NH3 yield rate of 2.36 mmol h−1 cm−2 at a low applied potential of −0.33 V vs. RHE, a high Faradaic efficiency (FE) of 98.8 %, and long-term operation stability at 1800 mg-N L−1 NO3−, outperforming most of the recently reported catalysts. At a NO3− concentration as low as 15 mg-N L−1, it still delivers a high FE of 86.9 % and an NH3 selectivity of 93.8 %. Finite-element method and density functional theory calculations reveal that the Cu11Ag3 exhibits reduced adsorption energy barrier of N intermediates, favorable water dissociation for H generation and high energy barrier for H2 formation, while its tip-enhanced enrichment promoting NO3− accumulation.

Changhong Wang; Zhengyang Liu; Quanxiao Peng; Dandan Xing; Tao Hu; Feng Du
Angewandte Chemie (International ed. Internet), 2025 64 (3) - EI SCIE

摘要 : Electrochemical reduction of nitrate to ammonia (NRA) offers a sustainable approach for NH3 production and NO3− removal but suffers from low NH3 yield rate (<1.20 mmol h−1 cm−2). We present bimetallic Cu11Ag3 nanotips with tailored local environment, which achieve an ultrahigh NH3 yield rate of 2.36 mmol h−1 cm−2 at a low applied potential of −0.33 V vs. RHE, a high Faradaic efficiency (FE) of 98.8 %, and long-term operation stability at 1800 mg-N L−1 NO3−, outperforming most of the recently reported catalysts. At a NO3− concentration as low as 15 mg-N L−1, it still delivers a high FE of 86.9 % and an NH3 selectivity of 93.8 %. Finite-element method and density functional theory calculations reveal that the Cu11Ag3 exhibits reduced adsorption energy barrier of N intermediates, favorable water dissociation for H generation and high energy barrier for H2 formation, while its tip-enhanced enrichment promoting NO3− accumulation.

Li Peng Gan; Juan Li; Fan Shi; Zhuo Zou; Ke Jiang Li; Zhuan Zhuan Shi
Analytica Chimica Acta, 2024 1308 - EI SCIE

摘要 : Metal-organic frameworks (MOFs) have been used to detect uric acid (UA), but still very challenging to achieve a low detection limit due to the low inferior conductivity of MOFs. Herein, three different N-doped ZIF-67-derived carbons were synthesized for the first time by one-step co-pyrolysis of 2-methylimidazole with cobalt nitrate (CN), cobalt acetate (CA) or cobalt chloride (CC) toward UA sensing. Afterwards, the cobalt nitrate-derived Co particle (Co/CN) supported by N-doped ZIF-67-derived carbon displays extremely low detection limit and high sensitivity for UA, outperformed all reported MOFs-based UA sensors. More interestingly, it was discovered that the high valence Co 4+ within the Co/CN sample produced in high-acidic environment can intercalate in the frame for a bridge adsorption between two reaction sites, which boosted simultaneous 2-electron transfer, while Co 3+ only allows an end-adsorption structure for one-electron transfer being the rate determining step. Furthermore, the bridge adsorption mode of UA on Co 4+ -based catalyst was also verified by theoretical DFT calculations and XPS experiment. This work holds great promise for a selective and sensitive UA sensor for practical bioscience and clinic diagnostic applications while shedding lights in fundamental research for innovative designs and developments of high-sensitive electrochemical sensors.

Tao Hu; Mengting Wang; Lijun Ren; Chang Ming Li; Chunxian Guo
Journal of Physical Chemistry Letters, 2024 15 (12) - EI SCIE

摘要 : The active component of copper-based materials for electrocatalytic nitrate reduction to ammonia (NRA) remains unclear due to the susceptibility of oxidation of copper. Using density functional theory calculations, NRA pathways are evaluated on low-index crystal surfaces Cu2O (111), CuO (111), and Cu (111) at different pH. Cu2O (111), with abundant undercoordinated Cu atoms on the surface, shows easier adsorption of NO3– than Cu (111) or CuO (111). NRA on CuO (111) is hindered by the large ΔG of adsorption of NO3– and hydrogenation of NO. Thus, Cu (111) and Cu2O (111) contribute most to the NRA activity while CuO (111) is inert. Three key steps of NRA on copper-based catalysts are identified: adsorption of NO3–, NO → NOH/ NHO, and NH3 desorption, as the three can be rate-determining steps depending on the local environment. Moreover, previous experimentally detected NH2OH on copper-based catalysts may come from the NRA on Cu2O (111) as the most probable pathway on Cu2O (111) is NO3– → NO3 → NO2 → NO → NHO → NHOH → NH2OH → NH2 → NH3 → NH3(g). At high reduction potential, CuOx would be reduced into Cu, so the effective active substance for NRA in a strong reduction environment is Cu.

Hui Zhang; Qianqian Jin; Tao Hu; Xiaochun Liu; Zezhong Zhang; Chunfeng Hu
Journal of advanced ceramics (Print), 2023 12 (6) - EI SCIE

摘要 : Twin boundaries have been exploited to stabilize ultrafine grains and improve mechanical properties of nanomaterials. The production of the twin boundaries and nanotwins is however prohibitively challenging in carbide ceramics. Using a scanning transmission electron microscope as a unique platform for atomic-scale structure engineering, we demonstrate that twin platelets could be produced in carbides by engineering antisite defects. The antisite defects at metal sites in various layered ternary carbides are collectively and controllably generated, and the metal elements are homogenized by electron irradiation, which transforms a twin-like lamellae into nanotwin platelets. Accompanying chemical homogenization, α-Ti3AlC2 transforms to unconventional β-Ti3AlC2. The chemical homogeneity and the width of the twin platelets can be tuned by dose and energy of bombarding electrons. Chemically homogenized nanotwins can boost hardness by ~45%. Our results provide a new way to produce ultrathin (< 5 nm) nanotwin platelets in scientifically and technologically important carbide materials and showcase feasibility of defect engineering by an angstrom-sized electron probe.

Hongjiu Zhu; Qiulin Li; Heng Zhang; Jiawang Liu; Juan Li; Zhuo Zou
Journal of Physical Chemistry C, 2023 -1 - EI SCIE

摘要 : A green process to produce an efficient and inexpensive electrocatalyst toward hydrogen evolution reaction (HER) is of importance for hydrogen energy. Here, an efficient HER electrocatalyst is made by electrochemically depositing Co2P quantum dots (QDs) on MoS2-carbon cloth (Co2P QDs/MoS2-CC). Due to the MoS2 porous structure, ∼3 nm Co2P QDs uniformly deposit on MoS2. The produced unique 3D-structured Co2P QDs/MoS2-CC not only prevents an agglomeration of the active material and improves the diffusion rate of H2 but also renders large accessible surface area and hierarchical pores for high-density reaction sites and enhanced mass transport rate. Experimental results and theoretical analysis of this unique heterostructure indicate that the evolution process of hydrogen is dominated by proton adsorption, and the introduction of sufficient edge active sites can significantly promote the HER. As a consequence, the hierarchical Co2P QDs/MoS2-CC electrocatalyst affords an ultra-low overpotential (41 mV at a current density of 10 mA cm–2) that ranks the best among all reported MoS2 HER catalysts and exhibits excellent durability in 1 M KOH solutions, thus holding great promise for the practical application while shedding on fundamentals to nanoengineering an efficient electrocatalyst.

Feng Du; Zhikun Yao; Jikai Xiang; Jingsha Li; Changhong Wang; Chunmei Zhang
Applied Surface Science, 2023 608 - EI SCIE

摘要 : To design high-performance electrocatalysts with desired electronic structures is critical to facilitate the conversion of pollutant nitrate (NO 3 − ) to value-added ammonia (NH 3 ) at ambient condition. Nevertheless, the current electrocatalysts for NO 3 − -to-NH 3 still face low Faradaic efficiency and selectivity. We present here a heteroatoms co-doped strategy using phosphorus (P) and oxygen (O) to tune electronic structure of copper (Cu) nanocrystals to form highly active surface for selective NO 3 − -to-NH 3 . By combing experimental results and theoretical calculation, it is found that the heteroatom P, O-doping can negatively shift the Cu d -band center, which optimizes adsorption energies of intermediates, especially for NO 3 − and NH 3 . The P, O-doped Cu nanocrystal exhibits an efficient 8-electron transfer process for NO 3 − -to-NH 3 . It achieves both high NO 3 − conversion rate (91.09 %) and NH 3 Faradaic efficiency (91.72 %) in high concentration NO 3 − electrolyte (1.0 M KOH + 1400 ppm NO 3 − -N), retaining its potential applications in practical NO 3 − -to-NH 3 .

Cheng, Renfei; Wang, Junchao; Hu, Tao; Zhao, Yiming; Liang, Yan; Wang, Xiaohui
Journal of Materials Science & Technology, 2023 165 - EI SCIE

摘要 : MXenes have promises in myriad applications by virtue of two-dimensional nature and adjustable functional groups. To achieve the applications, MXenes are always first prepared in the form of aqueous suspension. However, fast degradation caused by the attack of dissolved oxygen and water molecules is the main obstacle to the application of MXenes. It has come to light that the degradation preferentially takes place at defective sites and edges where defects enrich. To tackle this problem and increase the stability, herein, using Ti3C2Tx MXene as a model material, we report a simple yet efficient strategy for long term storage of MXene suspension by introducing glycerol, a typical polyhydric alcohol. The effectiveness of the strategy is evidenced by structural compositional and morphological investigations. Glycerol protects the defective sites of MXene flakes through restricting water and/or oxygen molecules from reactive sites. This is supported by ab initio molecular dynamics simulations that form hydrogen bonds between MXene and glycerol molecules just over defective sites. Following this mechanism, other polyhydric alcohols, such as ethylene glycol and propylene glycol, are also effective in stabilizing Ti3C2Tx MXene suspension. The strategy based on polyhydric alcohols has the potential to be extended to other MXenes, solving the most urgent challenge in the field of MXene engineering. © 2023

Cheng, Renfei; Wang, Junchao; Hu, Tao; Zhao, Yiming; Liang, Yan; Wang, Xiaohui
Journal of Materials Science & Technology, 2023 165 - EI SCIE

摘要 : MXenes have promises in myriad applications by virtue of two-dimensional nature and adjustable functional groups. To achieve the applications, MXenes are always first prepared in the form of aqueous suspension. However, fast degradation caused by the attack of dissolved oxygen and water molecules is the main obstacle to the application of MXenes. It has come to light that the degradation preferentially takes place at defective sites and edges where defects enrich. To tackle this problem and increase the stability, herein, using Ti3C2Tx MXene as a model material, we report a simple yet efficient strategy for long term storage of MXene suspension by introducing glycerol, a typical polyhydric alcohol. The effectiveness of the strategy is evidenced by structural compositional and morphological investigations. Glycerol protects the defective sites of MXene flakes through restricting water and/or oxygen molecules from reactive sites. This is supported by ab initio molecular dynamics simulations that form hydrogen bonds between MXene and glycerol molecules just over defective sites. Following this mechanism, other polyhydric alcohols, such as ethylene glycol and propylene glycol, are also effective in stabilizing Ti3C2Tx MXene suspension. The strategy based on polyhydric alcohols has the potential to be extended to other MXenes, solving the most urgent challenge in the field of MXene engineering. © 2023