Inorganic Chemistry Frontiers
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2024
·Vol. 11
·期 23
·8383-8391
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IF 6.1
Chen Zhang,Gao Xu,Qifeng Liang,Li Liang,Zebo Fang,Rong Wu,Shunhang Wei,Lei Wang,Xiaoxiang Xu
ZnIn2S4 nanosheets with tunable concentration of dual vacancies (i.e. Zn vacancy and S vacancy) were prepared and used for photocatalytic H2O2 production. Introducing dual vacancies effectively promotes exciton dissociation, facilitates O2 adsorption, and reduces the free energy of subsequent activation and protonation of adsorbed O2. These intriguing properties endow ZnIn2S4 with excellent performance for sacrificial agent-free H2O2 photosynthesis via a two-step single-electron oxygen reduction reaction pathway under AM 1.5 and visible-light irradiation. Almost double amounts of H2O2 can be produced over ZnIn2S4 with dual vacancies compared to pristine ZnIn2S4 without vacancies. Corresponding SCC efficiency and AQY at 420 ± 20 nm reached ∼0.031% and 0.34%, respectively. In addition, the abundant dual vacancies inhibit H2O2 decomposition because of enhanced hydrophilicity. This work provides a new strategy to improve the photocatalytic performance of ZnIn2S4 through defect engineering and brings new mechanistic insights into the role of these defects.
研究领域:
材料科学
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环境科学
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化学
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产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2025
·
IF 21.1
Kaiyang Shi,Changlin Yu,Jie Yuan,Weiya Huang,Kangqiang Lu,Zechao Zhuang,Jinrong Huo,Yu Xie,Erhuan Zhang,Dingsheng Wang,Kai Yang
Photocatalytic nitrogen fixation (PNF) under mild conditions is a promising approach to sustainable ammonia (NH 3 ) synthesis. However, PNF normally encounters many challenges, such as inefficient charge separation, poorly exposed active sites, and sluggish multi-electron/proton-involved steps. Here, we design a step (S)-scheme WS 2-x /La 1 -WO 2.9 heterojunction through integrating rich oxygen/sulfur dual-vacancies and loading rare-earth La single atoms. The as-prepared photocatalyst achieves a high NH 3 generation rate of 124.9 μmol∙g −1 ∙h −1 , which is 4.4, 1.7 and 1.2-fold those of pristine WO 3-x , WS 2-x and WS 2-x /WO 2.9 , respectively. Further in-depth characterizations and theoretical calculations reveal a synergistic photocatalytic effect in WS 2-x /La 1 -WO 2.9 , mainly due to the regulated collaborative dual defects and a lower energy d −π* occupation orbital from the modulation of La-modified W site. This leads to significantly reducing the reaction barrier in the rate-limiting step and elucidating the key intermediate processes (-NH 2 , -NH 2 NH 2 ) of the nitrogen fixation reaction. Our study creates a comprehensive strategy, analogous to the “three birds with one stone” method, offering new insights into advancing PNF.
研究领域:
材料科学
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催化化学
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产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2024
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IF 9.4
Chong Chen,Qiuhao Li,Fengqing Wang,Changjiang Hu,Jun Ma
Precise defect engineering of photocatalysts is highly demanding but remains a challenge. Here, we developed a facile and controllable γ-ray radiation strategy to assemble dual-vacancies confined MoS 2 -CdS-γ nanocomposite photocatalyst. We showed the solvated electron induced homogeneous growth of defects-rich CdS nanoparticles, while the symbiotic • OH radicals etched flower-like 1T/2H MoS 2 substrate surfaces. The optimal MoS 2 -CdS-γ exhibited a H 2 evolution rate of up to 37.80 mmol/h/g under visible light irradiation, which was 36.7 times higher than that of bare CdS-γ, and far superior to those synthesized by hydrothermal method. The microscopic characterizations and theoretical calculations revealed the formation of such unprecedented dual-sulfur-vacancies ensured the tight interfacial contact for fast charge separation. Besides, the existence of 1T-MoS 2 phase further improved the conductivity and strengthened the adsorption interaction with H + intermediate. Therefore, the radiolytic radical chemistry offered a facile, ambient and effective synthetic strategy to improve the catalytic performances of photocatalytic materials.
研究领域:
材料科学
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纳米技术
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光催化
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化学工程
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产品关联
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
·
2023
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IF 7.7
Wujian Zhang,Zhiling Huang,Lianyang Zhang,Yue Meng,Zheming Ni,Haodong Tang,Shengjie Xia
Defect (vacancy) engineering can modulate the catalyst surface atoms and electrons, which is a low-cost and effective modification strategy for Z-scheme heterojunction . In this paper, metal and non-metal double vacancies (V Zn+O ) Z-scheme heterojunction photocatalysts (BiOCl/ZnS−V Zn+O ) were synthesized for the degradation of norfloxacin (NOR) for the first time. The results show that the built-in electric field of BiOCl/ZnS−V Zn+O catalyst induces the directional migration of photogenerated carriers, which greatly improves the carrier migration and separation efficiency. The introduced nonmetallic (O) vacancies can lower the conduction band of BiOCl, while the metallic (Zn) vacancies can enhance the valence band of ZnS. Due to the synergistic efficiency formed by the double vacancies and Z-scheme heterojunction, BiOCl/ZnS−V Zn+O showed excellent performance in photodegradation of NOR (97.9% degradation rate of 20 mg/L NOR in 50 min photodegradation). In addition, the mechanism of action, intermediates and degradation pathways of photodegradation were discussed in detail.
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
APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Jiahui Chen,Yue Meng,Zhiling Huang,Bo Xie,Zheming Ni,Shengjie Xia
Defect engineering advantages include regulating the band structure of photocatalytic materials, inhibiting the recombination of photoelectron-hole pairs, and promoting the conversion of photogenerated electrons into active radicals. In this paper, bismuth molybdate (Bi 2 MoO 6 ) photocatalysts with double vacancies (V Bi-O -BMO) were prepared by solvothermal and ionic eutectic solvent methods. EPR, TEM, and XPS results confirmed the successful construction of oxygen and bismuth vacancies on Bi 2 MoO 6 . The photocatalytic performance of the prepared catalysts was investigated by photodegradation of levofloxacin hydrochloride (LVF) under visible light. The double vacancies markedly enhanced the photocatalytic properties of Bi 2 MoO 6 , with the photodegradation rate of V Bi-O -BMO reaching 88.36 % for 40 mg/L LVF within 60 min. Kinetic studies have demonstrated that the reaction rate constant of V Bi-O -BMO can reach 0.0351 min −1 , which is 3.2 times higher than that of bulk-BMO. This can be attributed to the favorable synergistic effect of oxygen and bismuth double vacancies. V O not only captures oxygen and electrons, facilitating the generation of superoxide radicals ( O 2 − ), but also elevates the conduction band position and boosts the reduction capability of Bi 2 MoO 6 . V Bi not only captures photogenerated holes (h + ) to directly impact LVF degradation, but also promotes interfacial charge transfer and inhibits the recombination of electron-hole pairs. Furthermore, the intermediates and degradation pathways of LVF photodegradation were surmised based on the LC-MS analysis. The reaction mechanism of LVF photodegradation by V Bi-O -BMO was elucidated through the application of the free radical pathway. This study demonstrates a methodology for the creation of double vacancies in catalysts and the significant potential of V Bi-O -BMO for the remediation of antibiotic residues in water under visible light.
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
APPLIED SURFACE SCIENCE
·
2021
·
IF 6.707
Yinjun Lin,Yuanyuan Yang,Wenting Guo,Lifen Wang,Ruiqin Zhang,Yonggang Liu,Yunpu Zhai
Vacancy engineering has been a very active research area in the field of photocatalysis. The electronic/band structure of carbon nitride can be tuned by introducing vacancies. However, the hydrogen production rate of carbon nitride modified only by a single defect is not significant. Therefore, we have constructed nitrogen-oxygen double vacancy modified carbon nitride by a simple two-step method. Especially, the photocatalytic performance of DACN-2 was 11.7 times and 5.8 times better than that of carbon nitride and oxygen-doped carbon nitride, respectively. The increase of specific surface area along with more available active sites, the pull-up of conduction band position and more efficient separation of photogenerated electron-hole pairs accounted for the improvement of hydrogen evolution performance. Moreover, the double vacancy was the separation center of the photogenerated charges, which accelerated the separation of photogenerated electrons and holes. This research provided a new concept for the design of defective carbon nitride and laid the foundation for the development of more effective photocatalysts in the future.
研究领域:
材料科学
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能源化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Hongyuan Yang,Jiexian Liu,Ziliang Chen,Ruirui Wang,Ben Fei,Huixiang Liu,Yanhui Guo,Renbing Wu
Prussian blue analogues (PBA) have been explored as electrocatalyst for the hydrogen evolution reaction, however, they suffer from poor electrical conductivity and blocked active sites and thus usually operate at overpotentials drastically above thermodynamic requirement. Herein, we report a creation of unconventional anion (cyano group) and cation (cobalt) bi-vacancies to boost CoFe-PBA for HER through a rapid tannic acid (TA) etching strategy. The combined experimental and theoretical investigations indicate that the introduction of bi-vacancies would be favorable to exposure of accessible active sites, optimizing the electron density of CoFe PBA, and lowering the reaction energy barrier. As a result, the TA-etched CoFe PBA nanocubes supported on nickel foam (NF) (CoFe-PBA@TA/NF) exhibit outstanding HER catalytic activity with an overpotential of only 86 mV at 10 mA cm −2 , which is not only significantly lower than bare PBA supported on NF (158 mV), but also comparable to the commercial Pt/C catalyst.
研究领域:
材料科学
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电化学
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产品关联
DOI
高影响因子
ACTA MATERIALIA
·
2021
·
IF 8.203
Xuejia Wang,Ting Su,Yunan Luo,Lijun Quan,Linping Zhong,Ruizhi Li,Ting Zhou,Mengjiao Liu,Yan Zhao,Xin Lai,Jian Bi,Daojiang Gao
Regarded as a promising anode material, CoMoO 4 can reveal higher theoretical capacity (980 mAh g −1 ) in the context of completely reversible electrochemical reaction. Unfortunately, the large volume expansion, low conductivity and inferior cyclic stability are non-negligible, which have greatly limited its further development and application. Herein, a series of CoMo 1- x Si x /2 O 4-2 x ( x = 0, 0.1, 0.15, 0.2 and 0.25) anode materials have been successfully synthesized through a solid-state method. This heterovalent atom doped strategy can not only provide cationic vacancy (Mo vacancy) but also generate anionic vacancy (O vacancy). The results demonstrate that all the Si doped CoMoO 4 samples exhibit superior electrochemical performances than that of the pure CoMoO 4 although the produce of the dual vacancies has negligible influence on the microstructures of CoMoO 4 , which should be attributed to the synergistic effect of the Mo vacancy and O vacancy and thus leading to the lower optical band gap, the enhanced conductivity and the faster transport of lithium ions and electron. Particularly, when the content of Si-doping is set as 0.05, the obtained CoMo 0.9 Si 0.05 O 3.8 sample displays the highest capacity (847.4 mAh g −1 ) up to 300 cycles at a current density of 200 mA g −1 . This work paves an effective strategy for constructing dual vacancies to promote the electrochemical performance of transition metal oxide anode materials.
研究领域:
材料科学
·
能源存储与转换
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
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2022
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IF 3.898
Peiyin Chen,Yanxiong Fang,Kaihong Xie,Yao Chen,Yang Liu,Hongliang Zuo,Weijian Lu,Baoyu Liu
The development of polyoxometalates for olefin oxidation is critical to achieving the green chemical process of the C5 fraction further processing. Di-lacunary silicotungstic anions were easily obtained by continuously adjusting the pH instead of the traditional step-by-step method, which exhibited excellent performance in the catalytic oxidation of cyclopentene (CPE) to aldehydes or alcohols. The 93.69% CPE conversion and 97.15% total product selectivity (41.38% for glutaraldehyde (GA) and 55.77% for 1,2-cyclopentanediol (1,2-diol) were achieved by using H 2 O 2 as the oxidant and acetonitrile as the solvent. Through complementary characterization, it was found that the optimized di-lacunary silicotungstic polyoxometalate retained a complete Keggin structure, and exhibited better catalytic activity and stability than the mono-lacunary or saturated silicodecatungstate because it exposed more catalytic active centers. Furthermore, in situ FT-IR spectra was utilized to monitor the reaction process, revealing the formation of the active species W(O 2 ) on the di-lacunary silicotungstic polyoxometalate and the intermediate epoxycyclopentane during the catalytic oxidation of cyclopentene.
研究领域:
化学工程
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催化材料科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Ting Liang,Zebin Yu,Yuejing Bin,Shiming Zhang,Jingwen Wei,Yujia Liu,Tingting Zhu,Songyu Fan,Yuxiang Shen,Shuangfei Wang,Yanping Hou
Inefficient separation and sluggish transfer of photogenerated charges on the photocatalyst is one of the bottlenecks for CO 2 photocatalytic reduction. In this study, the ZnSe/ZnWO 4 heterojunction with tungsten vacancies and oxygen vacancies (ZZ-30%-Vw,o) was synthesized by hydrothermal process and post-etching method for CO 2 reduction. Various characterizations showed superior structural and optical properties of the ZZ-30%-Vw,o heterojunction; results of ESR and work function calculation demonstrated that the heterojunction conformed to S-scheme charge transfer mechanism. Results of various tests and density functional theory (DFT) calculation confirmed the existence of W and O vacancies, as well as the locally polarized electric field (PEF). The PEF and the built-in electric field (IEF) could not only accelerate carriers separation and transfer, but also enhance CO 2 adsorption and activation, thus enhancing photocatalytic activity toward CO 2 reduction. The ZZ-30%-Vw,o composite exhibited the highest CO yield of 96.91 µmol/g/h, approximately 21.0 times of the ZnSe . Moreover, the ZZ-30%-Vw,o possessed favorable structure-performance stability. The COOH* was the most important intermediate during CO 2 reduction, and possible CO 2 reduction pathways and mechanism were proposed. This work paves a feasible way for improving photocatalytic activity via introducing dual surface vacancies on heterojunction photocatalysts.
研究领域:
材料科学
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环境科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
Nature Communications
·
2024
·Vol. 15
·期 1
·1-13
·
IF 14.7
Gong Yaru,Dou Wei,Lu Bochen,Zhang Xuemei,Zhu He,Ying Pan,Zhang Qingtang,Liu Yuqi,Li Yanan,Huang Xinqi,Iqbal Muhammad Faisal,Zhang Shihua,Li Di,Zhang Yongsheng,Wu Haijun,Tang Guodong
N -type polycrystalline SnSe is considered as a highly promising candidates for thermoelectric applications due to facile processing, machinability, and scalability. However, existing efforts do not enable a peak ZT value exceeding 2.0 in n -type polycrystalline SnSe. Here, we realized a significant ZT enhancement by leveraging the synergistic effects of divacancy defect and introducing resonance level into the conduction band. The resonance level and increased density of states resulting from tungsten boost the Seebeck coefficient. The combination of the enhanced electrical conductivity (achieved by increasing carrier concentration through WCl 6 doping and Se vacancies) and large Seebeck coefficient lead to a high power factor. Microstructural analyses reveal that the co-existence of divacancy defects (Se vacancies and Sn vacancies) and endotaxial W- and Cl-rich nanoprecipitates scatter phonons effectively, resulting in ultralow lattice conductivity. Ultimately, a record-high peak ZT of 2.2 at 773 K is achieved in n -type SnSe 0.92 + 0.03WCl 6 .
研究领域:
材料科学
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热电学
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固体物理学
✓ 已验证
DOI
高影响因子
Chem Catalysis
·
2023
·
IF 9.4
Xiuzheng Zhuang,Jianguo Liu,Yangqi Ji,Xiaojun Wu,Xinghua Zhang,Lungang Chen,Qi Zhang,Longlong Ma
Summary Pharmaceutical synthesis keeps close ties with the development of heterogeneous catalysts ; in this work, we report a facile way to prepare cobalt nanoparticles encapsulated by a graphene-shelled matrix, whose catalytic activity for a wide range of primary amines is proved to be broadly effective. As determined by its structural features, such a graphene-shelled matrix is characterized by surface defects such that inner metallic atoms are individually pulled outside by the divacancy sites; as a result, the delivery of metallic sites facilitates the easy substitution of the –NH 2 moiety toward functionalized and structurally diverse molecules by directly activating the C=O or C–N bonds in varied substrates, providing cost-effective access to numerous amines and other precursors for more complex drug products. In addition, the performance of this catalyst in a continuous test can reach at least 180 h without any loss of efficiency, which can be mainly ascribed to the protection of graphene-shelled structures.
研究领域:
药物化学
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催化
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材料科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）