CHEMICAL ENGINEERING JOURNAL
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2022
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IF 16.744
Ying-juan Hao,Yue-guang Ma,Xiao Zhang,Jianjun Li,Saifei Wang,Xuemin Chen,Fa-tang Li
Developing low-temperature, high-efficiency and anti-poisoning catalysts is crucial for VOCs removal. CeO 2 materials with different electron density are prepared via regulation on facets and oxygen vacancies. It reveals that high electron density of materials plays a decisive role in the production of reactive oxygen species, reducibility of surface lattice oxygen and improvement of photothermocatalytic activity for toluene oxidation compared with highly concentrated oxygen vacancies and large special surface area. Photothermocatalytic conversion rate for 1500 ppm of toluene over the optimized defective CeO 2 could reach 93 % at 145 °C under the gas hourly space velocity of 60,000 mL·g −1 ·h −1 . H 2 -TPR result shows that excessive oxygen vacancies are detrimental to the appearance of mobile reactive oxygen species due to the strong chemical interaction and the escape probability of surface lattice oxygen of CeO 2 . It is also found that the decrement of electron density of the recovered sample can account for the slight catalyst deactivation, accompanied by the increasement of bulk oxygen vacancies in the recovered sample, exclusive of disappearance of surface oxygen vacancies, aggregations and deposition of organic carbon. This work provides an insight into the design of high-efficiency non-noble catalysts applied to VOCs removal.
研究领域:
环境科学
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催化材料
✓ 已验证
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2023
·Vol. 33
·期 20
·2213999
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IF 19
Yizhong Zhang,Liuchang Wang,Ruichi Zhang,Chao He,Lixia Jia,Xunliang Wang,Xuemin Feng,Tianxiang Jiang,Baolong Xie,Xiaolei Ma,Junrui Cao,Yuhui Ma,Xin Tan,Tao Yu
Because of spontaneous agglomeration effect and undesirable electronic state of Zr sites on the surface, zirconium (hydro)oxides generally exhibit suboptimal defluoridation capacity. Herein, a template confinement-ligand anchoring strategy is developed by utilizing confined growth of zirconium hydroxide (ZH) inside chitosan hydrogel beads (CHB) and subsequent anchoring of fumaric acid (fm) on its surface Zr sites in a monodentate mononuclear coordination mode. This technique leads to uniform dispersion of ultrafine fmZH (≈3.4 nm) and tunable electron density at the Zr sites. Due to the electron-withdrawing ability of fm, electron-delocalized Zr sites increase the orbital energy level matching and vacate Zr 4d orbitals to promote hybridization with the F 2p orbitals. Ultimately, robust Zr F bond can be formed as a result of reduced the adsorption energy toward fluoride ions. The defluoridation capacity shows positive linear relationship with the electron extraction ability of ligands. The saturation adsorption capacity and dynamic treatment capacity of CHB@fmZH are 10.8 and 45.9 times higher than that of CHB@ZH, respectively, owing to high electron extraction (0.098 e − ) of fm. This study offers a novel insight into the design and synthesis of high-efficiency metal oxide adsorbents by steering its surface metal sites’ electronic state through ligand effect.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2023
·Vol. 15
·期 13
·6321-6332
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IF 6.7
Huimin Wang,Tao Feng,Lincai Wang,Weiju Hao
Development of economical, efficient and durable non-noble metal electrocatalysts for the hydrogen/oxygen evolution reaction (HER/OER) holds great promise, but still faces great challenges. Herein, a strategy of doping metal borides with rare earth metal oxides and introducing silicon carbide (SiC) quantum dots has been explored to develop efficient bifunctional electrocatalysts. A novel electrocatalyst consists of SiC quantum dot-decorated CeOx–NiB supported on nickel foam via a one-step mild electroless plating reaction (denoted as CeOx–NiB/SiC@NF). Notably, the modulated electron density of the CeOx–NiB/SiC@NF electrode significantly boosts the electrochemically active surface area and electron transfer, and optimizes the hydrogen/water absorption free energy, which delivers current densities of 50 mA cm−2 and 10 mA cm−2 at overpotentials of only 131 mV and 234 mV for the HER and the OER, respectively. The target electrode requires only 1.43 V to provide 10 mA cm−2 for overall water splitting in 1.0 M KOH. Moreover, the electrode also exhibits good stability and durability at the industrial-grade current density (0.5–1 A cm−2). This work provides a new idea for the development of efficient and durable non-precious metal catalysts.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MATERIALS LETTERS
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2019
·
IF 3.019
Yuqiao Wang,Chuanyong Jian,Wenting Hong,Qian Cai,Wei Liu
Cobalt disulfide (CoS 2 ) for hydrogen evolution reaction (HER) suffers from unfavorable hydrogen adsorption properties due to the strong interaction between the adsorbed H and the intensely electropositive cobalt atom. Herein, we successfully demonstrate a general strategy to improve the hydrogen evolution activity of CoS 2 by modulating the surface electron density. The selenium doped CoS 2 (Se-CoS 2 ) nanowires arrays exhibit a durable activity for electrochemical hydrogen evolution in 0.5 M H 2 SO 4 solution to deliver 10 mA cm −2 at the overpotential of only 139 mV. Our density functional theory studies consistently confirm that the surface electron density of CoS 2 has been effectively manipulated by Se doping. The adsorbed hydrogen binding energy to Se-CoS 2 can be optimized to provide an optimal condition for electron and proton transferring to the adsorbed H 2 , thereby promoting HER activity of CoS 2 .
研究领域:
材料科学
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电化学
✓ 已验证
DOI
高影响因子
Progress in Natural Science-Materials International
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2016
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IF 1.753
Yu Bai,Chunlei Wang,Xingyi Zhou,Junling Lu,Yujie Xiong
Pd typically exhibits relatively low catalytic activity in CO oxidation, as CO is apt to be adsorbed on Pd to poison the surface for O 2 activation. In this Letter, we report that this limitation can be overcome by integrating Pd with TiO 2 . The TiO 2 was coated on Pd nanocubes with a controllable thickness using atomic layer deposition (ALD) method. Given the different work functions of TiO 2 and Pd, the electrons in TiO 2 semiconductor will flow toward Pd. With the electron density increased on Pd, the adsorption of CO to Pd will be weakened while the oxygen activation can be facilitated. Meanwhile, the interface-confined sites at Pd-TiO 2 may further enhance the oxygen activation. As the species adsorption and activation are strongly correlated with electron density, the performance of Pd-TiO 2 in CO oxidation turns out to depend on the TiO 2 thickness, which determines the number of transferred electrons, within a certain range (<1.8 nm). This work provides a new strategy for enhancing catalytic performance through tailoring charge densities in hybrid catalysts.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMOSPHERE
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2024
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IF 8.1
Long Chen,Miao Li,Ying Yang,Xiaoqing Qiu
The strong metal-support interactions (SMSI) can profoundly affect the electronic state of platinum (Pt) cocatalysts, which plays a dominant role for photocatalytic activity in the supported photocatalysts. However, the conventional Pt/g-C 3 N 4 photocatalysts usually shows negligible SMSI effect because of the lack of the reducible species. Herein, we demonstrate that the linker engineering of UiO66-type MOFs can effectively strengthen the SMSI and optimize the electron density of Pt nanoparticles on g-C 3 N 4 nanosheets. The enhancement of electron-donating ability of the ligand functional groups effectively enriches the electron density of Pt cocatalysts, thus accelerating the photocatalytic hydrogen evolution rate. The results show that CN@Pt@UiO66-NA (the electron-donating functional group modified) exhibits the excellent photocatalytic hydrogen evolution activity (4.22 mmol g −1 h −1 ), which is 2.7 times that of CN@Pt@UiO66-NO 2 (the electron-withdrawing functional group modified).
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2020
·
IF 4.65
Minglu Li,Chaozhu Shu,Anjun Hu,Jiabao Li,Yu Yan,Miao He,Jianping Long
Lithium-oxygen batteries (LOBs) are considered to be one of the most competitive energy storage devices due to their high theoretical energy density . However, challenges including poor catalytic activity and durability of the oxygen electrode seriously hinder the in-depth development of LOBs. Adjusting the surface electronic structure of the oxygen electrode provides a new prospect for realizing highly efficient electrocatalysts . In this contribution, we report that atomic-scale palladium (Pd) involving in MoSe 2 (Pd–MoSe 2 ) is capable of adjusting the in-plane electron density of MoSe 2 via spontaneous interface chemical reactions, thereby accelerating the electron migration along the in-plane direction. The synergy between the created Se vacancies and Pd atoms can further increase the electroactive sites on the Pd–MoSe 2 surface, which is conducive to improving the catalytic activity of the electrode and thereby accelerating the kinetics of oxygen electrode reactions. The results show that Pd–MoSe 2 based LOBs exhibit excellent electrochemical performance such as high Coulombic efficiency (97.81%) as well as extended cycle life (1952 h). This work shows that the adjustment of in-plane electron density by exotic metal atom is a viable strategy to improve the catalytic activity of layered transition metal selenide, which provides the possibility of developing highly efficient electrocatalysts for LOBs.
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
FUEL
·
2023
·
IF 7.4
Yanqing Shi,Cai Guo,Huajing Zhou,Liang He,Shaoyun Shan,Tianding Hu
Rational modulation of the local electron density of Cu active site is the key to improve the efficient transfer hydrogenation (CTH) of furfural (FF) on the surface of catalysts with low Cu-loadings. In this paper, a CuMgAl/LSC catalyst with lower Cu content (<3.5 % wt ) was prepared by using porous biochar as a carrier and exploiting the local dispersion and electron-modulation effects of structural elements of hydrotalcite laminates. CTH experiments showed that the conversion of FF and the selectivity of FA could reach more than 99.0 % in isopropanol solution at 170 °C and within 1 h. Catalyst characterization and density functional theory (DFT) calculations demonstrated that the Cu(I) species was the main active site during the CTH process of FF. Doping laminate metals (i.e., Mg, Al) can not only form electron-rich centers by local electron modulation of the active site through the coordination structure of Cu-O-M, lowering its D-band center and achieving higher catalytic activity; Due to the Jahn-Teller effect, the local spatial misalignment of Cu sites formed, which can reduce the risk of over-hydrogenation and improve the FA selectivity. In addition, it can be also found that the Coulomb tractive force of reactive intermediates can lead to the crystal surface reconstruction and structure deterioration of Cu species. The new discovery of the deactivation mechanism can provide a reference for the future design of copper-based catalysts in CTH process of FF.
研究领域:
催化化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2019
·
IF 14.229
Meijiao Qu,Yimin Jiang,Miao Yang,Shu Liu,Qifei Guo,Wei Shen,Ming Li,Rongxing He
Highly active and stable catalysts toward hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is extremely important but challenging for overall water splitting. Herein, a strategy by modulating surface electron densities is adopted to design new catalyst: the Ru-NiFe-P nanosheets on 3D self-supported nickel foam was developed by doping a small quantity of Ru into transition metals phosphates. The designed catalyst displays excellent electrocatalytic performance in 1.0 M KOH, with low overpotentials of 44 mV at 10 mA cm −2 for HER and 242 mV at 100 mA cm −2 for OER. Particularly, it only needs 1.47 V to yield 10 mA cm −2 for overall water splitting. Density functional theory calculations reveal that Ru-incorporated NiFe-P can generate new active sites on Ru atoms and increase the catalytic activity of original P sites leading to an optimal Gibbs free-energy on catalysts surface. This work offers a new perspective for designing admirable electrocatalysts.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Quan Chen,Zhenya Tang,Hao Li,Min Wu,Qing Zhao,Bo Pan
Heavy metal is a serious environmental issue mostly because of their toxicity and bioaccumulation. The recovering and recycling of the adsorbents became a bottleneck in heavy metal removal through adsorption. A hybrid adsorbent MnFe 2 O 4 @CAC showed great application potential because of its easy regeneration. However, as for other commonly used adsorbents, the removal performance of different types of heavy metals are distinctively different, but the mechanism is still unclear. To address this knowledge gap, the electron-scale behavior and adsorption mechanism of six divalent cations (Cu(II), Cd(II), Pb(II), Co(II), Ni(II), Hg(II)) on MnFe 2 O 4 @CAC were investigated in-depth combining experimental analysis and density functional theory (DFT) calculations. The experimental results showed the order of adsorption: Ni(II) > Cu(II) > Co(II) > Pb(II) > Cd(II) > Hg(II). The reaction from transition state to the final product was the rate-determining step for the Cu(II), Pb(II), Co(II) and Ni(II) adsorption, while the reaction from reactant to intermediate controlled the adsorption rate of Cd(II) and Hg(II). The main adsorption mechanisms were surface complexation and ionic exchange, which were further confirmed by the spectroscopic (Fourier Transform infrared spectroscopy, FT-IR and X-ray photoelectron spectroscopy, XPS) characterizations and DFT calculations. In addition, the electron density of state (DOS) results indicated the 4s orbit of the cations most easily to be occupied by the d electrons of MnFe 2 O 4 . The order of adsorption affinity agreed well with the apparent adsorption, and was decided by the electronic empty orbit and ionic electron cloud size of the cations. The results of the current study provide an in-depth understanding on the adsorption mechanism of heavy metals and offer a theoretical guidance for improving their removal efficiency.
研究领域:
环境科学
·
材料科学
·
理论化学
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2022
·
IF 8.035
Li Wang,Wende Hu,Zhou Shang,Xiaoming Cao,Yun Guo,Jiayi Li,Qiyuan Gu,Ke Li,Xiaobo Li
Enhancement in oxidation performance of Co 3 O 4 -based catalysts can be achieved by regulating K, and the promotion effects were strongly depended on the amount and existing state of K. Only the surface Co substituted by optimum amount of K (CoK 2 with K/Co mole ratio of 1.56 × 10 -2 ), unexpectedly high activities could be achieved. The specific activity of CoK 2 were 20 and 2.7 times higher than that of Co 3 O 4 for CO oxidation and CH 4 combustion. However, the excess K in the form of carbonate or nitrate deactivated the active sites, so the performance against K amount behaved as a volcano curve. Based upon the electronic and structural modification of K, the electron density of Co and O simultaneously decreased which weakened CO adsorption strength and improved the C H bond activation. Since efficiency in various pollutants removal, CoK 2 could be considered as a promising candidate for noble metal catalysts.
研究领域:
化学
·
催化材料科学
✓ 已验证
产品关联
DOI
高影响因子
ChemSusChem
·
2022
·Vol. 15
·期 15
·e202200752
·
IF 9.14
Helei Wei,Aidong Tan,Zhipeng Xiang,Jie Zhang,Jinhua Piao,Zhenxing Liang,Kai Wan,Zhiyong Fu
Graphical Ni doping enhances CO 2 reduction : The Ni doping dramatically modulated the electronic structure of the Bi nanosheet by increasing its p-orbital electronic density states and shifting towards the Fermi level. The resultant strong orbital hybridization between Bi and the π* orbitals of CO 2 facilitates the formation of *OCHO intermediates and favors its activation, leading to high activity and selectivity toward HCOOH during CO 2 electroreduction. Electrochemical reduction of CO 2 (CO 2 RR) to value-added chemicals is an effective way to harvest renewable energy and utilize carbon dioxide. However, the electrocatalysts for CO 2 RR suffer from insufficient activity and selectivity due to the limitation of CO 2 activation. In this work, a Ni-doped Bi nanosheet (Ni@Bi-NS) electrocatalyst is synthesized for the electrochemical reduction of CO 2 to HCOOH. Physicochemical characterization methods are extensively used to investigate the composition and structure of the materials. Electrochemical results reveal that for the production of HCOOH, the obtained Ni@Bi-NS exhibits an equivalent current density of 51.12 mA cm −2 at −1.10 V, which is much higher than the pure Bi-NS (18.00 mA cm −2 at −1.10 V). A high Faradaic efficiency over 92.0 % for HCOOH is achieved in a wide potential range from −0.80 to −1.10 V, and particularly, the highest efficiency of 98.4 % is achieved at −0.90 V. Both experimental and theoretical results reveal that the superior activity and selectivity are attributed to the doping effect of Ni on the Bi nanosheet. The density functional theory calculation reveals that upon doping, the charge is transferred from Ni to the adjacent Bi atoms, which shifts the p-orbital electronic density states towards the Fermi level. The resultant strong orbital hybridization between Bi and the π* orbitals of CO 2 facilitates the formation of *OCHO intermediates and favors its activation. This work provides an effective strategy to develop active and selective electrocatalysts for CO 2 RR by modulating the electronic density state.
研究领域:
材料科学
·
电化学
·
催化反应
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）