ACS Applied Energy Materials
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2020
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IF 4.473
Huijuan Han,Yang Yang,Jiafang Liu,Xiuzhen Zheng,Xulin Wang,Sugang Meng,Sujuan Zhang,Xianliang Fu,Shifu Chen
Photocatalytic nitrogen fixation is considered as a very promising technology to solve the high-energy consumption problem in industrial ammonia synthesis. Because of the mildness of reaction conditions, its development is still limited by the low reaction efficiency and unknown reaction mechanism. Inspired by the mechanism of biological nitrogen fixation in nature, Zn3In2S6 with different sulfur sources is prepared to study the effects of cation defects on the adsorption, activation, and reaction in photocatalytic nitrogen fixation. Because of the electron-rich property of zinc vacancies in Zn3In2S6 nanosheets, it can effectively activate the N≡N triple bond, thereby increasing the rate of kinetic reduction. With the activation of N2 molecules on zinc vacancies, the existing protons obtained from methanol (solvent) will greatly accelerate the electron transfer between interfaces during the nitrogen reduction reaction. Notably, Zn3In2S6 with rich Zn vacancies exhibits higher activity (355.2 mg L–1 gcat–1, 15 times) than Zn3In2S6 with poor vacancies in nitrogen fixation. This work describes the contribution of zinc vacancies to the fixation and activation of nitrogen molecules, which is very important to establish a highly effective system of photocatalytic nitrogen fixation.
研究领域:
材料科学
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催化化学
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环境科学
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产品关联
DOI
高影响因子
Green Energy & Environment
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2024
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IF 10.7
Yi-lei Li,Xu-jia Liu,Yun-biao Wang,Ying Liu,Rui-hong Liu,Hui-ying Mu,Ying-juan Hao,Xiao-jing Wang,Fa-tang Li
Adjusting the interfacial transport efficiency of photogenerated electrons and the free energy of hydrogen adsorption through interface engineering is an effective means of improving the photocatalytic activity of semiconductor photocatalysts. Herein, hollow ZnS/NiS nanocages with ohmic contacts containing Zn vacancy (V Zn -ZnS/NiS) are synthesized using ZIF-8 as templates. An internal electric field is constructed by Fermi level flattening to form ohmic contacts, which increase donor density and accelerate electron transport at the V Zn- ZnS/NiS interface. The experimental and DFT results show that the tight interface and V Zn can rearrange electrons, resulting in a higher charge density at the interface, and optimizing the Gibbs free energy of hydrogen adsorption. The optimal hydrogen production activity of V Zn -ZnS/NiS is 10,636 μmol h −1 g −1 , which is 31.9 times that of V Zn -ZnS. This study provides an idea for constructing sulfide heterojunctions with ohmic contacts and defects to achieve efficient photocatalytic hydrogen production.
研究领域:
材料科学
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能源科学
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化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
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2024
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IF 4.1
Ying Chen,Minghua Lin,Zihang Peng,Yumei Shu,Minhua Ai,Li Wang,Xiangwen Zhang,Ji-Jun Zou,Lun Pan
Homojunction is a viable alternative strategy to realize excellent charge separation for enhancing photoelectrocatalytic performance. However, the feasible regulation of the homojunction interface remains challenging. Herein, a ZnO n-p homojunction with the piezotronic effect is constructed via an in-situ solvothermal method for enhancing photoelectrocatalytic activity. ZnO nanorods are transformed from n-type to p-type ZnO nanoparticles with zinc vacancies, leading to the n-p homojunction. The optimal NPZ-36 exhibits a superior photocurrent density of 1.56 mA/cm 2 at 1.23 V vs. RHE and a high incident photon to current conversion efficiency of 75 % at 360 nm. Impressively, with the merits of inherent piezoelectric and photocatalytic properties of wurtzite ZnO, the piezoelectric-enhanced photoelectrochemical activity originates from the simultaneous promotion of bulk charge transfer and interfacial charge separation in ZnO n-p homojunction. The photocurrent density of NPZ-36–900 can reach to 2.02 mA/cm 2 under the stirring rate of 900 rpm, which is 2.1 times higher than that of pure ZnO photoanode.
研究领域:
材料科学
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光催化
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产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2022
·Vol. 11
·期 4
·1793-1800
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IF 14.511
Yu Nie,Tingting Bo,Wei Zhou,Huilin Hu,Xiang Huang,Huaiyuan Wang,Xin Tan,Lequan Liu,Jinhua Ye,Tao Yu
How to regulate the energy barrier of *COOH is the rate determining step of the photocatalytic reduction of CO2 to produce gaseous CO. Herein, an appropriate Zn vacancy on ZnIn2S4 was synthesised to achieve the desired photocatalytic CO2 reduction capacity (CO: 5.63 mmol g−1 h−1) and selectivity (CO: 97.9%). Various sulfhydryl groups were selected to regulate the Zn vacancy formation in ZnIn2S4, which directly generated the unsaturated coordination state of the sulfur adjacent to the Zn vacancy accompanied by less electrons when compared to ZnIn2S4 without Zn vacancy. Comprehensive experimental analysis and theoretical calculations demonstrated that the appropriate Zn vacancy tuned the Gibbs free energy of *COOH from the endothermic process to the exothermic process in the process of the photoreduction CO2. This work provided an engineering method for cation vacancies and improvement of the efficiency of photocatalytic CO2 reduction by adjusting the energy barrier of intermediate.
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
Solar RRL
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2021
·Vol. 5
·期 11
·2100536
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IF 8.582
Yujie Liu,Qiaohong Zhu,Muhammad Tayyab,Liang Zhou,Juying Lei,Jinlong Zhang
Semiconductor supported noble metal nanoparticles are widely used in H 2 evolution. Due to the high cost and low catalytic efficiency of noble metals, single-atom catalysts (SACs) are considered as very potential materials to overcome these shortcomings. Herein, the construction of the ZnO–ZnS heterojunction with an excess amount of Zn vacancies promotes the separation of charge carriers and improves the utilization of electrons. Meanwhile, the zinc vacancies on ZnS provide effective anchor sites for Pt atoms, which is beneficial to obtain highly dispersed single Pt atoms catalyst (ZOS-SAPt). Due to the formation of an intermediate energy level by zinc vacancies, the introduction of Pt single atoms promotes the novel type-V electron transport from the conduction band of ZnO to the intermediate energy level and then to the Pt atom. The type-V electron transport not only retains the high reduction potential of photogenerated electrons, but also avoids the loss of carriers. The resultant ZOS-SAPt shows outstanding photocatalytic performance for H 2 evolution under simulated sunlight, reaching 9.6 mmol g −1 h −1 , which is 201 times that of ZnO–ZnS. These results provide important information for further development of photocatalysts.
研究领域:
材料科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
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2021
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IF 6.901
Haoyang Wu,Xiaoqing Zhang,Jiawei Xue,Hui Zhang,Lan Yang,Shikuo Li
Designing metal-cation defects with desired architectures is a big challenge for boosting electrochemical performances. Herein, we report ultrathin ZnNi layered double hydroxide (LDH) nanosheets with rich Zn vacancies (V Zn ) uniformly anchored on CuO nanowire skeletons for high performance capacitive electrode via a zeolitic imidazolate frameworks-8 derived approach. The optimized V Zn -defect electrode displays high area capacity of 3967 mF cm −2 at a current density of 2.0 mA cm −2 . Moreover, an all solid-state hybrid supercapacitor constructed with the V Zn -defect sample and activated carbon delivers a maximum energy density of 1.03 mWh cm −3 at a power density of 9.3 mW cm −3 . Mechanism studies indicate that V Zn regulates the electronic structure of ZnNi LDH nanosheets for electron conductivity and surface Faradaic reactions. The work may disclose the role of metal-cation defects in affecting the electrochemical activity at atomic level for developing high performance supercapacitors.
研究领域:
材料科学
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电化学
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能源存储与转换
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产品关联
DOI
高影响因子
ADVANCED MATERIALS
·
2025
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IF 26.8
Shengbin Xu,Yao Xiao,Puxian Xiong,Pan Zheng,Sheng Wu,Xuesong Wang,Yumin Yin,Haiqiang Fang,Chengan Wang,Yuexi Lu,Enhai Song,Jiulin Gan
Mechanoluminescence (ML), the emission of light under mechanical stimuli, shows great potential in passive sensing, wearable devices, and biomedical diagnostics. However, the practical application of ML materials is hindered by low intensity and poor self-recoverable performance. Herein, a Mn 4+ →Mn 2+ self-reduction strategy is presented to significantly enhance the self-recoverable ML performance of CaZnOS by inducing lattice defects and promoting distortion in its noncentrosymmetric hexagonal structure. This approach enhances the internal piezoelectric response and increases the maximum ML intensity up to 4 times. X-ray absorption near-edge structure, extended X-ray absorption fine structure, electron paramagnetic resonance, piezoresponse force microscopy, and density functional theory calculations reveal that the composite defects involving V O · · ${\mathrm{V}}_{\mathrm{O}}^{\cdot \cdot}$ and V Zn ′ ′ ${\mathrm{V}}_{{\mathrm{Zn}}}^{{\mathrm{^{\prime\prime}}}}$ are the key to the significant enhancement of ML. Furthermore, this strategy is successfully extended to rare-earth ions codoped systems, achieving a general enhancement of near-infrared ML emission. Based on these findings, a multilayer orthodontic sensor is developed, capable of real-time occlusal mapping and bite-force monitoring. The device exhibits sensitive response across 0–12 N and achieves 96.89% accuracy in occlusal localization through neuromorphic image recognition. This work offers a generalizable route toward ML performance optimization and paves the way for the development of advanced intelligent sensing technologies.
研究领域:
材料科学
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力致发光
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压电材料
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缺陷化学
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传感器与传感技术
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智能材料
✓ 已验证
产品关联
DOI
PubMed
高影响因子
DYES AND PIGMENTS
·
2016
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IF 4.055
M.M. Mikhailov,V.V. Neshchimenko,Chundong Li
This study carried out on the diffuse reflective spectra of zinc oxide modified by Al 2 O 3 , ZrO 2 , SiO 2 , CeO 2 , TiO 2 and Y 2 O 3 nanoparticles . It was established that during the modification are formed the solid solutions between zinc oxide and nanopowder as Al 2 ZnO 4 , ZrZnO 3 , Zn 2 SiO 4 , Ce x Zn (1−х) О y , Zn 2 TiO 4 , Y x Zn (1−x) O y . The diffuse reflection spectra of the modified powders are changed in the UV and visible range with a maximum at 395 nm. This band is determined by the intrinsic point defects in the crystal lattice of ZnO as interstitial zinc ions and zinc vacancy. In the IR region also recorded changes due to the absorption of OH-groups adsorbed on the surface modified zinc oxide.
研究领域:
材料科学
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光学
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纳米技术
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）