NANOTECHNOLOGY
·
2017
·Vol. 28
·期 39
·394003
·
IF 3.44
Tao Fang,Yongsheng Guo,Songhua Cai,Ningsi Zhang,Yingfei Hu,Shiying Zhang,Zhaosheng Li,Zhigang Zou
Many metal-oxide candidates for photoelectrochemical water splitting exhibit localized small polaron carrier conduction. Especially hematite (α-Fe2O3) photoanodes often suffer from low carrier mobility, which causes the serious bulk electron-hole recombination and greatly limits their PEC performances. In this study, the charge separation efficiency of hematite was enhanced greatly by coating an ultrathin p-type LaFeO3 overlayer. Compared to the hematite photoanodes, the solar water splitting photocurrent of the Fe2O3/LaFeO3 n–p junction exhibits a 90% increase at 1.23 V versus the reversible hydrogen electrode, due to enlarging the band bending and expanding the depletion layer.
研究领域:
材料科学
·
光电化学
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2019
·Vol. 8
·期 1
·334-341
·
IF 10.733
Guoqiang Zhang,Xun Yang,Chuanxin He,Peixin Zhang,Hongwei Mi
Photocatalytic systems capable of precisely regulating oxygen vacancy (OV) concentrations, which could help illuminate the effects of the OV concentration on N2 fixation activity, are still scarce. Here, we demonstrate that excessive OVs in TiO2, while increasing the adsorption activation capacity of N2 molecules, exhibit disappointing activity due to a decrease in charge separation efficiency. With optimized OV concentration, TiO2 can increase the charge separation efficiency 3-fold and show significant activation towards N2 molecules. The normalized N2 photofixation rate is 324.86 μmol h−1 g−1 (full spectrum) and the corresponding apparent quantum yield (AQY) under 365 nm illumination reaches 1.1%, which are relatively high levels compared to reports in the literature. The origin of this excellent activity is clearly attributable to the OV defect structures, which coordinate the charge separation efficiency and the dissociative adsorption capacity of N2. This work establishes the relationship between OV concentration and activity, and helps to construct a highly efficient nitrogen-fixing photocatalyst by optimizing the OV concentration.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL PHYSICS
·
2020
·Vol. 152
·期 24
·
IF 2.991
Zhu Jingxian,Jiang Wenshuai,Wang Bin,Niu Lijuan,Dong Chenxi,Qu Dan,An Li,Wang Xiayan,Sun Zaicheng
Mixed phase TiO 2 (Degussa P25) exhibits superior photocatalytic performance and stability due to the formation of the hetero-phase junction between anatase and rutile. However, the large bandgap limits its visible light activity. CdS is a photocatalyst with a broad light absorption band up to 550 nm. Constructing a hetero-phase junction will greatly promote the photocatalytic activity of CdS. In this work, the one-step solvothermal method was used to synthesize CdS hetero-phase junction with both hexagonal wurtzite (WZ) and cubic zinc blende (ZB) phases. The ratio of WZ and ZB phases can be tuned by adjusting the solvent ratio and reaction time to construct type I junction and effectively separate the photogenerated electron–hole pair. Under visible-light illumination, the optimal photocatalytic activity of the prepared material reaches 7.96 mmol h −1 g −1 , and the quantum efficiency is 36.7% at 420 nm, which is three times higher than that of any single-phase sample (cubic or hexagonal phase) and maintains high photocatalytic stability as well. It is expected that this work will provide a feasible prospect for the practical application of high-efficiency homogeneous junction photocatalysts.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CRYSTAL GROWTH & DESIGN
·
2024
·
IF 3.2
Furong Ye,Wen Liu,Changcun Han,Yahao Zhao,Peng Liu,Hui Wang
This study introduces Au nanoparticles into ZnIn2S4 through electrodeposition to overcome the limitation of rapid charge carrier recombination on the photoelectrochemical efficiency. The strong coupling of Au nanoparticles with the FTO substrate not only serves as an electron acceptor but also exhibits a surface plasmon resonance (SPR) effect, significantly enhancing charge carrier separation efficiency. Experimental results demonstrate that the introduction of Au nanoparticles notably improves the light absorption capability of ZnIn2S4, enhancing its solar energy conversion efficiency and rendering it an effective photoelectrocatalytic catalyst. Electrochemical analysis shows that the modified sample achieves a photocurrent density of 0.52 mA/cm2 at 1.23 V (vs RHE), which is 2.15 times that of pure ZnIn2S4, validating the potential of this approach for photoelectrocatalytic applications.
研究领域:
材料科学
·
能源转换
✓ 已验证
产品关联
DOI
高影响因子
Inorganic Chemistry Frontiers
·
2024
·
IF 6.1
Lijun Liu,Wenya Tang,Lu-Yang Zuo,Hui-Tao Fan,Bo Li,Liya Wang
Semiconductor photocatalytic hydrogen evolution (PHE) has emerged as a feasible solution to address the problem of energy shortage. Hydrogen energy can thus be developed by creating a photocatalyst with a high activity for producing hydrogen and an effective charge transfer route. This study describes the preparation of innovative hierarchical ZnMn2O4@ZnIn2S4 (ZMOZ) ball-in-ball hollow microspheres as photocatalysts using a straightforward solvothermal technique. Remarkably, the PHE rate of the 10% ZMOZ can reach 11.12 mmol h–1 g–1, it roughly 4.9 greater than pure ZnIn2S4 (ZIS). Aside from the benefits of building heterojunctions, the regulation of morphology such as hollow structures that can provide more exposed active sites and enhance the light-absorption capability by internal multilight scattering. Through the use of density functional theory calculations (DFT), X-ray photoelectron spectroscopy (XPS), photoluminescence (PL) spectra as well as time-resolved PL (TRPL) spectroscopy also demonstrate that the charge separation efficiency in the composite was notably improved. This work offered a cost-effective and environmentally friendly method for utilizing visible light to construct an effective PHE.
研究领域:
材料科学
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Huadong Liu,Jingliang Cheng,Hao Sun,Xiaoyu Sun
The rapid charge recombination in Bi 2 WO 6 severely limits its photocatalytic efficiency for antibiotic wastewater treatment. To address this, Eu 3+ -doped Bi 2 WO 6 was synthesized via controlled hydrothermal method, exhibiting 2.5-fold enhanced tetracycline (TC) degradation kinetics (0.05889 min −1 ) and 23 % higher efficiency than pristine Bi 2 WO 6 under visible light. Comprehensive characterization reveals three synergistic mechanisms: first, Eu 3+ incorporation induces lattice distortion and charge imbalance, generating oxygen vacancies that act as electron traps to suppress recombination; second, UV-Vis DRS shows bandgap narrowing from 2.8 to 2.3 eV enabling broader light absorption; third, electrochemical impedance spectroscopy demonstrates 3.1-fold improved charge separation efficiency. ESR and radical trapping experiments identify h + and ·O 2– as the dominant active species, with the former contributing approximately 68 % of the degradation activity according to quantitative analysis. The catalyst retains 88.57 % activity after four cycles, showing superior stability. This work provides atomic-level insights into rare-earth doping effects on charge carrier dynamics, offering a viable strategy for designing visible-light photocatalysts.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2021
·
IF 5.316
Wendi Huang,Xinyan Xiao,Mingli Lu,Yu Xiao
A novel BiOCl/Bi 5 O 7 I (BOC-BOI) heterojunction was prepared by growing ultrathin 2D BiOCl nanosheets in situ on the surface of 3D Bi 5 O 7 I microspheres . The 2D/3D heterostructure of BOC-BOI composites inhibited the agglomeration of BiOCl nanosheets, and benefited the multiple reflection and refraction of light, which greatly enhanced the absorption and utilization of light. The 50-BOC-BOI composite showed 97.7% degradation efficiency of rhodamine B (RhB) after 70 min Xe light irradiation. And its apparent degradation rate constant ( k ) was 0.0377 min −1 , being 4.9 and 15.1 times than that of pristine BiOCl (0.0077 min −1 ) and Bi 5 O 7 I (0.0025 min −1 ), respectively. The enhanced photocatalytic activity of BOC-BOI composites was attributed to stronger light capture ability, more abundant active sites and higher charge carrier separation efficiency, confirmed by UV-Vis DRS, SEM, TEM, BET, Zeta potential and electrochemical characterizations. The free radical capture experiments showed that the main active species in this system were holes (h + ) and superoxide free radicals (·O 2 − ). Combining the results of UV-Vis DRS and Mott-Schottky test, a reasonable type II heterojunction mechanism was proposed.
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
CRYSTENGCOMM
·
2020
·Vol. 22
·期 12
·2219-2226
·
IF 3.117
Rui Zhang,Jianlei Kuang,Qipeng Lu,Qi Wang,Peng Sun,Wenxiu Liu,Shu Yin,Wenbin Cao
SnO sheets with tunable thickness were synthesized by a hydrothermal method. The thickness of the SnO sheets could be delicately controlled by adjusting the amount of PEG added. It was found that the thickness of the SnO sheets reduced from 1 μm to 150 nm with the increase in PEG. PEG was preferentially adsorbed on the (001) facets of SnO and thus inhibited the crystal growth in the <001> direction, which determined the final shape to be sheets with reduced thickness. The reduced thickness of SnO offered a shorter pathway along the two-dimensional conducting path and thus induced rapid charge transfer and high separation efficiency. Meanwhile, the reduced thickness of the SnO sheets induced an enlarged band gap and correspondingly increased the redox ability of SnO, which was confirmed by UV-vis absorbance spectroscopy and Mott–Schottky plots. Benefiting from the improved charge separation efficiency and the stronger redox ability, enhanced photocatalytic degradation efficiency was demonstrated by the SnO sheets with reduced thickness. The SnO sheets with the thinnest thickness (150 nm) exhibited optimal photocatalytic activity in the degradation of methylene blue (MB) under fluorescent light irradiation (350–800 nm); the activity was about 3.5 times higher than that of the SnO sheets with 1 μm thickness.
研究领域:
材料科学
·
化学
✓ 已验证
DOI
高影响因子
Heliyon
·
2024
·
IF 3.4
Jingshan Cui,Zhurui Shen,Gaoqing Cao,Xiangxu Zhao,Weizun Li
To address the global challenge posed by excessive carbon dioxide emissions, our research pioneers the transformation of CO 2 into valuable hydrocarbon fuels. Central to this approach is the innovation of photocatalysts, engineered to exhibit exceptional photoresponse characteristics. In this research, the CsBr@CuBr 2 photocatalyst was innovatively synthesized through a straightforward and effective one-pot method. The catalyst displayed remarkable efficacy, achieving a CO 2 photoreduction rate of 201.47 μmol g −1 within just 4 h. The incorporation of CsBr into CuBr 2 effectively captures excited-state electrons, thereby significantly enhancing charge separation efficiency. Utilizing in situ DRIFTS and DFT theoretical analysis, the experiment reveals the complex process of CO 2 photoreduction to CO. The results of this experiment provide breakthrough insights for the systematic design of metal bromide heterostructures, which possess robust CO 2 adsorption/activation potential and notable stability.
研究领域:
材料科学
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环境科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ELECTROCHIMICA ACTA
·
2020
·
IF 6.215
Weicheng Cui,Hongye Bai,Jianpeng Shang,Fagen Wang,Dongbo Xu,Jinrui Ding,Weiqiang Fan,Weidong Shi
Constructing the high-performance photoanode is critical to improve photoelectrochemical (PEC) efficiency, but it is still an inevitable challenge to rationally fabricate the organic-inorganic hybrid-photoanode system. For the first time, we report a novel hybrid-photoanode built from ultrathin NiFe-MOF and TiO 2 by a sacrifice template method. The in-situ etch of NiFe-layered double hydroxide (LDH) on the surface of TiO 2 has been successfully realized in the coordination environment, for creating coordinately unsaturated metal sites on NiFe-MOF. The coordinately unsaturated metal sites could significantly promote the water oxidation kinetic , compared with conventional electrode/electrolyte interface. The photocurrent density of the NiFe-MOF/TiO 2 has reached about 3.35 times of bare TiO 2 at 1.23 V (vs. RHE), and the incident photon to current conversion efficiency (IPCE) value has been improved up to 42% (at 390 nm). The significant augment of the charge injection ( η injection ) of 92.8% and charge separation ( η separation ) efficiency of 37.4% has also been exhibited. Moreover, NiFe-MOF/TiO 2 shows a long-term stability ( < 10% decay) after 4 h of continuous illumination. This work provided a novel and rational strategy about the integration of the inorganic semiconductor and organic MOF , which can provide a new insight into understanding MOF-based catalysts for PEC water splitting.
研究领域:
材料科学
·
能源科学
✓ 已验证
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2024
·
IF 7.4
Ruina Xuan,Jiwen Chen,Yixin Dou,Zhuo Jiang,Xiaofang Li,Deng Ding,Chunlei Wang,Juntao Yan,Linbing Sun
Dual-co-catalyst-modified photocatalysts enhance charge separation efficiency, but the traditional dual co-catalyst is still difficult to get a high separation efficiency due to size and aggregation. Herein, we report bimetallic MIL-53(Fe/Mn) as dual co-catalysts with separate electron and hole mediators. CdS NPs were in-situ grown into MIL-53(Fe/Mn) at varying ratios. 20 %CdS/MIL-53(Fe/Mn) composites shown optimum photocatalytic CO 2 reduction activity. The XPS results shown the strong interaction between CdS and MIL-53(Fe/Mn). The EPR measure proved the carriers of CdS can be transferred to MIL-53(Fe/Mn) oxidation cluster by the oxo-Fe(III)/Fe(II) and oxo-Mn(II)/Mn(III) redox cycling, and the results also suggest the oxo-Fe(III) and oxo-Mn(II) were redox active sites. We believe the approach that bimetallic MOFs act as dual cocatalyst to improve the photocatalytic activity would open a new avenue for the separation efficiency of photo-generated charge carriers.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
Nature Communications
·
2025
·Vol. 16
·期 1
·1-9
·
IF 15.7
Wang Shuo,Li Chenyang,Qi Yu,Zhang Jiaming,Wang Ningning,Liu Meng,Zhang Boyang,Cai Xuefen,Zhang Hongbo,Wei Su-huai,Ma Guijun,Yang Jingxiu,Chen Shanshan,Zhang Fuxiang
Charge separation of particulate photocatalysts has been considered as the rate-determining step in artificial photocatalysis since the finding of Honda-Fujishima effect, whose efficiency is generally much lower than that of natural photosynthesis. To approach its upper limit, it requires the photoexcited electrons and holes be efficiently transferred to the spatially separated redox reaction sites over a single photocatalyst particle. Herein, it is demonstrated the spatial charge separation among facets of BiVO 4 :Mo can be notably promoted by creating an electron transfer layer. It not only favors electrons to transfer to its surface, but also promotes the built-in electric field intensity of the inter-facet junction by over 10 times. Consequently, the charge separation efficiency of the modified BiVO 4 :Mo with loading of CoFeO x oxidation cocatalyst exceeds 90% at 420 nm, comparable to that of the natural photosynthesis system, over which notably enhanced photocatalytic activities are achieved. Our findings demonstrate the effectiveness of electron transfer layer in intensifying charge separation of particulate photocatalysts.
研究领域:
材料科学
·
光催化技术
·
能源转换
✓ 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）