| 1. |
- Zhao, Xue, et al.
(författare)
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Efficient degradation of Health-threatening organic pollutants in water by atomically dispersed Cobalt-Activated peroxymonosulfate
- 2022
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Ingår i: Chemical Engineering Journal. - : Elsevier. - 1385-8947 .- 1873-3212. ; 450
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Tidskriftsartikel (refereegranskat)abstract
- Degrading health-threatening organic pollutants (HTOPs) in water systems through advanced oxidation processes (AOPs) is an effective way to treat environmental wastewater; however, such processes require advanced catalysts. This study combined complexation effects and structural confinement strategies to rapidly prepare Co2+-isolated metal–organic framework polymers and utilized a thermal treatment process to achieve the efficient anchoring of atom-dispersed Co in a boron–carbon-nitrogen matrix (denoted as SACoN/BCN), which can improve the utilization of Co catalytic sites. SACoN/BCN effectively activated peroxymonosulfate (PMS), with the ratio and mineralization rate of sulfamethazine (SMT) removed by degradation within 40 min reached 95.2 % and 70.0 %, respectively. Radical inhibition experiments and electron paramagnetic resonance (EPR) tests showed that 1O2 generated from SACoN/BCN-activated PMS was the key reactive oxygen species that promoted HTOP degradation. Density functional theory calculations revealed that, following the introduction of electron-deficient B heteroatoms, electrons in PMS will be injected into SACoN/BCN, thereby realizing strong adsorption and further activation of PMS. The cytotoxicity of SACoN/BCN is almost negligible because of the chemical bonding (or entrapment) of Co atoms in the inorganic boron–carbon-nitrogen matrix, thereby preventing Co from forming mobile CoII ions in the aqueous system. This research provides information for advanced catalysts for the removal of HTOPs and experimental and theoretical inspiration for the preparation of single-atom catalysts for advanced oxidation processes and the mechanism of PMS activation.
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| 2. |
- Zhao, Xue, et al.
(författare)
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Electron modulation and morphology engineering jointly accelerate oxygen reaction to enhance Zn-Air battery performance
- 2023
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Ingår i: Advanced Science. - : John Wiley & Sons. - 2198-3844. ; 10:8
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Tidskriftsartikel (refereegranskat)abstract
- Combining morphological control engineering and diatomic coupling strategies, heteronuclear Fe-Co bimetals are efficiently intercalated into nitrogen-doped carbon materials with star-like to simultaneously accelerate oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). The half-wave potential and kinetic current density of the ORR driven by FeCoNC/SL surpass the commercial Pt/C catalyst. The overpotential of OER is as low as 316 mV (η10), and the mass activity is at least 3.2 and 9.4 times that of mononuclear CoNC/SL and FeNC/SL, respectively. The power density and specific capacity of the Zn-air battery with FeCoNC/SL as air cathode are as high as 224.8 mW cm−2 and 803 mAh g−1, respectively. Morphologically, FeCoNC/SL endows more reactive sites and accelerates the process of oxygen reaction. Density functional theory reveals the active site of the heteronuclear diatomic, and the formation of FeCoN5C configuration can effectively tune the d-band center and electronic structure. The redistribution of electrons provides conditions for fast electron exchange, and the change of the center of the d-band avoids the strong adsorption of intermediate species to simultaneously take into account both ORR and OER and thus achieve high-performance Zn-air batteries.
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| 3. |
- Peng, Yan, et al.
(författare)
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Cu Nanoparticle-Decorated Boron-Carbon-Nitrogen Nanosheets for Electrochemical Determination of Chloramphenicol
- 2022
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Ingår i: ACS Applied Materials and Interfaces. - : American Chemical Society (ACS). - 1944-8244 .- 1944-8252. ; 14:25, s. 28956-28964
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Tidskriftsartikel (refereegranskat)abstract
- In the present work, irregular Cu nanoparticle-decorated boron-carbon-nitrogen (Cu-BCN) nanosheets were successfully synthesized. A Cu-BCN dispersion was deposited on a bare glassy carbon electrode (GCE) to prepare an electrochemical sensor (Cu-BCN/GCE) for the detection of chloramphenicol (CAP) in the environment. Cu-BCN was characterized using high-resolution scanning transmission electron microscopy (HRSTEM), scanning electron microscopy (SEM), X-ray diffraction (XRD) analysis, and X-ray photoelectron spectroscopy (XPS). The performance of the Cu-BCN/GCE was studied using electrochemical impedance spectroscopy (EIS), and its advantages were proven by electrode comparison. Differential pulse voltammetry (DPV) was used to optimize the experimental conditions, including the amount of Cu-BCN deposited, enrichment potential, deposition time, and pH of the electrolyte. A linear relationship between the CAP concentration and current response was obtained under the optimized experimental conditions, with a wide linear range and a limit of detection (LOD) of 2.41 nmol/L. Cu-BCN/GCE exhibited high stability, reproducibility, and repeatability. In the presence of various organic and inorganic species, the influence of the Cu-BCN-based sensor on the current response of CAP was less than 5%. Notably, the prepared sensor exhibited excellent performance in real-water samples, with satisfactory recovery.
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| 4. |
- Zhao, Xue, et al.
(författare)
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BCN-Encapsulated Nano-nickel Synergistically Promotes Ambient Electrochemical Dinitrogen Reduction
- 2020
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Ingår i: ACS Applied Materials and Interfaces. - : AMER CHEMICAL SOC. - 1944-8244 .- 1944-8252. ; 12:28, s. 31419-31430
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Tidskriftsartikel (refereegranskat)abstract
- The electricity provided by solar or wind power can drive nitrogen in the atmosphere, combining with ubiquitous water to form ammonia, and distributed production methods can alleviate the irreversible damage to the environment caused by the energy-intensive Haber-Bosch process. Here, we have designed a novel Ni-doped BCN heterojunction (S/M-BOPS-1) as a catalyst for the electrochemical nitrogen reduction reaction (NRR). The ammonia yield rate and Faraday efficiency in NRR driven by S/M-BOPS-1 reach up to 16.72 mu g(-1) h(-1) cm(-2) and 13.06%, respectively. Moreover, S/M-BOPS-1 still maintains high NRR activity and excellent stability after recycling for eight times and long-time operation of 12 h. Using density functional theory calculations, we reveal a possible NRR path for N-2 to NH3 on Ni, BCN, and the S/M-BOPS-1 composite surfaces. The interaction between the BCN matrix and Ni nanoparticles promotes a synergetic effect for the electrochemical NRR efficiency due to the partial electron transfer from the Ni particles to BCN that inhibits hydrogen evolution reaction and decreases the rate-determining step on Ni surfaces toward NRR by similar to 1.5 times. Therefore, efficient NRR performance can be achieved by tuning the electronic properties of non-noble metals via the formation of a heterointerface.
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| 5. |
- Zhao, Xue, et al.
(författare)
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Copper confined in vesicle-like BCN cavities promotes electrochemical reduction of nitrate to ammonia in water
- 2021
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Ingår i: Journal of Materials Chemistry A. - : ROYAL SOC CHEMISTRY. - 2050-7488 .- 2050-7496. ; 9:41, s. 23675-23686
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Tidskriftsartikel (refereegranskat)abstract
- Electrochemical methods to convert high-concentration nitrates present in sewage into high-value-added ammonia do not just alleviate the problem of environmental pollution but also provide less energy-intensive alternatives to the Haber-Bosch process. In this work, a metal-boron organic polymer precursor was annealed at high temperature to obtain copper nanoparticles encapsulated in a vesicle-like BCN matrix (BCN@Cu). In the electrochemical reduction of nitrate (E-NIRR), this species exhibited excellent catalytic activity. Specifically, the ammonia yields of BCN@Cu under applied potentials of -0.3 V, -0.4 V, -0.5 V, and -0.6 V versus the reversible hydrogen electrode were 271.1 mu mol h(-1) mg(cat.)(-1), 354.8 mu mol h(-1) mg(cat.)(-1), 435.6 mu mol h(-1) mg(cat.)(-1), and 576.2 mu mol h(-1) mg(cat.)(-1), respectively, and the corresponding Faraday efficiencies were 86.3%, 88.0%, 89.3%, and 88.9%. Isotope labeling experiments with (NO3-)-N-15 confirmed that the detected ammonia had originated from the electrochemical reduction of NO3- on the catalyst surface. Moreover, the E-NIRR activity of BCN@Cu remained high even after using it ten consecutive times or 20 h of continuous operation, suggesting the practicality of the industrial application of BCN@Cu. The presence of copper was key in determining BCN@Cus E-NIRR activity, while the presence of boron greatly improved its catalytic performance. Furthermore, density functional theory calculations indicated that BCN does not itself promote the reaction but rather assists the dispersion of Cu nanoparticles, thereby expanding the catalysts active surface area.
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| 6. |
- Zhao, Xue, et al.
(författare)
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Efficient Ambient Electrocatalytic Ammonia Synthesis by Nanogold Triggered via Boron Clusters Combined with Carbon Nanotubes
- 2020
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Ingår i: ACS Applied Materials and Interfaces. - : American Chemical Society (ACS). - 1944-8244 .- 1944-8252. ; 12:38, s. 42821-42831
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Tidskriftsartikel (refereegranskat)abstract
- Currently, the development of stable electrochemical nitrogen reduction reaction (ENRR) catalysts with high N-2 conversion activity and low cost to instead of the traditional Haber-Bosch ammonia production process of high-energy consumption remains a great challenge for researchers. Here, we have immobilized reductive closo-[B12H11](-) boron clusters on a carbon nanotubes (CNT) surface and have successfully prepared a novel Au-CNT catalyst with extraordinary ENRR activity after adding HAuCl4 to the CNT-[B12H11](-) precursor. The excellent properties of ammonia yield (57.7 mu g h(-1) cm(-2)) and Faradaic efficiency (11.97%) make it possible to achieve using this Au-CNT catalyst in large-scale industrial production of ammonia. Furthermore, its outstanding cyclic stability and long-term tolerability performance make it one of the most cost-effective catalysts to date. Here, by means of density functional theory we disclose the associative mechanism of N-2-to-NH3 conversion on the Au(111) surface, providing visual theoretical support for the experimental results.
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| 7. |
- Zhao, Xue, et al.
(författare)
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Hydrophobic boron organic polymers : Ultra-high capacity of enrichment and storage for chloroform
- 2020
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Ingår i: Chemical Engineering Journal. - : ELSEVIER SCIENCE SA. - 1385-8947 .- 1873-3212. ; 385
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Tidskriftsartikel (refereegranskat)abstract
- Chloroform, a superstar widely applied as solvent, extractant, refrigerating fluid and adhesive, faces storage risks and environmental pressures. Herein, a brand-new strategy for storing and enriching chloroform is designed. It is shown that stable boron organic polymers BOPS-S3 with excellent hydrophobicity can be facilely prepared by combining Na-2[B12H12] and amphiphilic HBPB-14 molecules. The unique molecular structure of such as prepared polymers endows strong affinity with chloroform. BOPS-S3 possesses an ultra-high adsorption capacity of 46.9 g.g(-1) toward liquid chloroform, with a resulting gel that maintains a low volatilization rate. In addition, a stainless mesh coating with BOPS-S3 is shown to excellently remove chloroform vapor, likewise BOPS-S3 is shown efficient for removal of chloroform traces in water, with a residual amount lower than the allowable concentration in drinking water defined by the World Health Organization. This work provides a novel approach to store chloroform in transportation or other unstable conditions with unprecedented ramifications.
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| 8. |
- Zhao, Xue, et al.
(författare)
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Potassium ions promote electrochemical nitrogen reduction on nano-Au catalysts triggered by bifunctional boron supramolecular assembly
- 2020
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Ingår i: Journal of Materials Chemistry A. - : Royal Society of Chemistry (RSC). - 2050-7488 .- 2050-7496. ; 8:26, s. 13086-13094
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Tidskriftsartikel (refereegranskat)abstract
- The electrochemical way of reducing nitrogen to ammonia presents green and economic advantages to dial down irreversible damage caused by the energy-intensive Haber-Bosch process. Here, we introduce an advanced catalyst CB[7]-K-2[B12H12]@Au with highly dispersed and ultrafine nano-gold. The CB[7]-K-2[B12H12]@Au electrochemically driven ammonia yield and Faraday efficiency is as high as 41.69 mu g h(-1)mg(cat.)(-1)and 29.53% (at -0.4 Vvs.RHE), respectively, reaching the US Department of Energy (DOE) utility index of ambient ammonia production along with excellent cycle stability and tolerance that indicates a high potential of industrial practical value. Experimental results and theoretical calculations show that the key to an excellent electrochemical nitrogen reduction performance lies in the smart design of the CB[7]-K-2[B12H12]@Au catalyst combining the stable substrate anchored Au nanoparticles and K(+)ions that effectively prevent the hydrogen evolution reaction and polarize *N(2)leading to lowering of the rate determining step. This research will promote the further development of electrochemical ammonia production with low environmental impact.
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| 9. |
- Zhao, Xue, et al.
(författare)
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Simultaneous anchoring of Ni nanoparticles and single-atom Ni on BCN matrix promotes efficient conversion of nitrate in water into high-value-added ammonia
- 2022
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Ingår i: Chemical Engineering Journal. - : Elsevier. - 1385-8947 .- 1873-3212. ; 433:Part 2
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Tidskriftsartikel (refereegranskat)abstract
- Electrochemical synthesis of ammonia driven by clean energy is expected to realize the supply of ammonia for distributed production of industry and agriculture. Here, nickel nanoparticles and nickel in the form of single atoms were simultaneously anchored on the electrochemically active carrier BCN matrix through a structured domain strategy, which realized a high-efficiency, high-value-added, conversion of nitrate in sewage. Specifically, the electrochemical nitrate reduction reaction (NIRR) driven by BCN@Ni in alkaline media achieves an ammonia yield rate as high as 2320.2 μg h−1 cm−2 (at −0.5 V vs RHE), and Faraday efficiency as high as 91.15% (at −0.3 V vs RHE). Even in neutral and acidic media, the ammonia yield rates of NIRR driven by BCN@Ni are as high as 1904.2 μg h−1 cm−2 and 2057.4 μg h−1 cm−2, respectively (at −0.4 V vs RHE). The 15NO3- isotope labeling experiment verified that the recorded ammonia all came from the electrochemical reduction of NO3– on BCN@Ni. Density functional theory (DFT) calculations show that both nano-Ni and single-atom Ni in BCN@Ni have the ability to electrochemically convert NO3– into NH3, and that the addition of BCN can further promote the NIRR on Ni.
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| 10. |
- Zhao, Xue, et al.
(författare)
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Two-dimensional BCN matrix inlaid with single-atom-Cu driven electrochemical nitrate reduction reaction to achieve sustainable industrial-grade production of ammonia
- 2021
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Ingår i: APPLIED MATERIALS TODAY. - : Elsevier. - 2352-9407. ; 25
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Tidskriftsartikel (refereegranskat)abstract
- Electrochemical methods have been proven to effectively eliminate nitrates in sewage and convert them into high value-added ammonia products. Here, after annealing treatment of metal boron cluster organic polymers formed by the combination of 1,10-phenanthroline, Cu2+ and closo-[B12H12](2)(-), a Cu single-atom doped BCN (B-doped CN) with a diamond-shaped nanosheet structure was obtained. In the electrochem-ical reduction reaction of nitrate, BCN-Cu exhibits excellent catalytic activity, specifically: 1) the ammonia yield rate reached as high as 498.85 mu g h(-1) cm(-2), 1047.14 mu g h(-1) cm(-2), 1900.07 mu g h(-1) cm(-2) and 3358.74 mu g h(-1) cm(-2) at -0.3 V, -0.4 V, -0.5 V and -0.6 V vs reversible hydrogen electrode, respectively, and Faradaic efficiency is 95.90%, 97.28%, 98.23% and 97.37%; 2) after repeated use of BCN-Cu 10 times or continuous operation for 16 h, the activity against electrochemical reduction reaction of nitrate anions is almost unchanged. The (NO3-)-N-15 isotopic labeling experiment proved that the detected NH3 comes from the reduction of NO3- on BCN-Cu. Control experiments show that the presence of Cu determines whether BCN-Cu has the possibility of catalyzing electrochemical reduction reactions of nitrate, and the presence of the B element enhances the catalytic activity of BCN-Cu. Density functional calculations indicate that in the water phase the process of reducing NO3- to NH3 on Cu-0 is an exothermic reaction, and that the adsorption process of NO3- on Cu-0 is the rate-determining step.
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