JOURNAL OF CATALYSIS
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2024
·
IF 6.5
Jinni Shen,Yuhua Zhong,Jianhan Lin,Haifeng Li,Chengwei Qiu,Xu Liu,Xun Wang,Rong Hu,Jinlin Long,Xuxu Wang,Zizhong Zhang
Photocatalytic water splitting on metal oxides often faces oxygen evolution inefficiency, reflecting the complex interplay of its two half-reactions. Strategies like heterojunctions, cocatalyst loading, or noble metal nanoparticles addition have been explored to address this. Using γ-Ga 2 O 3 nanosheets as a model, we uncovered the formation of −O-O- species as the key barrier to stoichiometric splitting. To tackle this, a strategy was devised, Sr-doping to inhibit surface peroxidation. The resultant Sr-doped γ-Ga 2 O 3 (Sr-Ga 2 O 3 ) significantly improved activity and stability, achieving balanced H 2 and O 2 production under 125 W mercury lamp light. Upon further enhancement with Rh/Cr 2 O 3 cocatalyst via photoreduction, the Sr-Ga 2 O 3 /(Rh/Cr 2 O 3 ) composite demonstrated a remarkable 8.7 mmol·g −1 ·h −1 H 2 and 4.4 mmol·g −1 ·h −1 O 2 evolution rate, 8.3 times higher than γ-Ga 2 O 3 alone, with a 34.1 % quantum efficiency under 260 nm light. This represents a record performance for Ga 2 O 3 -based photocatalytic water splitting. Mechanistically, Sr doping alters surface chemistry to favor direct oxygen release. Our study elucidates molecular-level insights into non-stoichiometric splitting mechanisms and offers a potent strategy to boost metal oxide photocatalysts’ water-splitting efficiency.
研究领域:
材料科学
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环境科学
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能源化学
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产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Jian Chen,Siyuan Wang,Shuyun Wang,Rong Tang,Huan Chen
As a persistent contaminant with significant risks to environment, health and ecology, perfluorooctanoic acid (PFOA) is urgent to be treated from water. To improve the performance of commercial Ga 2 O 3 in the photocatalytic degradation of PFOA, a Bi 4 O 7 -Ga 2 O 3 composite was facilely obtained through a hydrothermal route, and characterized with diverse techniques. Batch tests were conducted to evaluate the impacts from the experimental conditions on PFOA degradation, where the Bi 4 O 7 -Ga 2 O 3 composite (GaBi10) exhibited optimized photocatalytic performance stems from the enhanced light response, improved separation of photo-generated carriers, and increased adsorption capacity, attributed by Bi 4 O 7 incorporation. Furthermore, a universal parameter, catalytic efficiency ( η ) is proposed for the quantitative comparison of photocatalytic performance across different studies, which demonstrate the outstanding performance of GaBi10 in PFOA degradation, defluorination and mineralization. The quenching tests and intermediates analysis were executed to explore the mechanism underlying the photocatalytic degradation, which indicated the degradation is initiated by h + , and other active species, ·O 2 – and ·OH, propel the mineralization of the intermediates derived from PFOA. The findings provide valuable insights for developing commercial photocatalyst and understanding photocatalytic degradation of PFOA.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
Catalysis Science & Technology
·
2024
·Vol. 14
·期 10
·2722-2729
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IF 4.4
Yuqiao Li,Dezheng Li,Huimin Liu,Yiming Lei,Rongda Zhao,Dehua He,Ze Zheng,Hui Luo,Aidi Liu
Photothermal dry reforming of methane (DRM), as an emerging branch of heterogeneous catalysis, could effectively convert CO2 and CH4 into high-value-added chemicals via the synergistic effect between thermochemical and photochemical processes. Herein, we report that loading Rh nanoparticles (NPs) on Ga2O3−x with oxygen vacancies improves CO2 conversion efficiency through photo-assisted DRM. On the Rh/Ga2O3−x catalyst, the photothermal catalytic CO2 conversion rate (112.0 μmol g−1 min−1) is 1.6 times that of the thermal reaction at 500 °C (71.9 μmol g−1 min−1). Rh2O3 and Ga2O3 as precursors are in situ reduced to Rh NPs and Ga2O3−x under the reductive DRM reaction atmosphere, respectively. Characterization results indicate that Rh NPs accelerate the DRM process by enhancing light absorption ability and charge transfer efficiency. Meanwhile, the oxygen vacancies in Ga2O3−x are beneficial for activating reactant molecules rapidly. In situ DRIFTS spectra showed that Rh NPs and oxygen vacancies served as reduction and oxidation sites during the photothermal DRM process. This work paves the way for the rational design of better photothermal catalysts in the future.
研究领域:
化学工程
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催化材料科学
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产品关联
DOI
高影响因子
Small Science
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2024
·Vol. 4
·期 11
·2400241
·
IF 11.1
Mingli Liu,Shuai Liu,Jian Yao,Yu Teng,Lin Geng,Alei Li,Lin Wang,Yunfei Li,Qing Guo,Zongjie Shen,Lixing Kang,Mingsheng Long
In recent years, wide-bandgap semiconductor β-Ga 2 O 3 material has been widely studied because of its excellent properties. Simultaneously, 2D metal oxides (2DMOs) have also become a focus of research owing to their superior stability and unique physical properties arising from quantum confinement effects. Therefore, the exploration of 2D β-Ga 2 O 3 is expected to reveal its novel electrical properties in electronic applications. However, the synthesis of high-quality 2D β-Ga 2 O 3 remains a formidable challenge. Herein, a confined space is constructed to synthesize high-quality 2D β-Ga 2 O 3 nanoflakes by enhancing the control of the kinetics of chemical vapor deposition process. In the device results, it is shown that the grown nanoflakes have excellent switching properties and potential artificial synaptic response characteristics. Based on this premise, an artificial recognition system for handwritten numerals is developed, achieving a peak recognition accuracy of approximately 96%. This system holds significant potential for application within an emerging neuromorphic recognition framework tailored for advanced driver-assistance systems. In this work, a new feasible pathway is provided for the synthesis of 2D non-layered oxides and the potential of 2D oxides in the field of neuroanalog electronics and recognition is shown, thereby advancing the fields of 2D β-Ga 2 O 3 electronics and 2DMOs electronics.
研究领域:
材料科学
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电子工程
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神经网络
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2019
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IF 8.355
Mingjie Li,Zebin Yu,Yanping Hou,Qing Liu,Lun Qian,Cuifang Lian,Xunzheng Rao,Xiaoting Yang
Ga 2 O 3 highlights the high energy band structure for redox reaction. However, information on noble metals and metal oxides deposited Ga 2 O 3 for contaminant elimination and the corresponding mechanisms is still lack. Here, metals and metal oxides deposited Ga 2 O 3 (labeled as M-P and MO-C; M = Ag, Pt, and Pd) were synthesized by photocatalytic and chemical deposition methods and confirmed with XRD and XPS. M-P and MO-C were applied in photocatalytic degradation of three typical contaminants: ciprofloxacin, ronidazole and rhodamine B. The ciprofloxacin and ronidazole degradation rates by Ag 2 O-C and rhodamine B degradation rate by Ag-P were 3.0, 2.7 and 2.4 times as high as those by pure Ga 2 O 3 . This research demonstrates that photocatalytic activities of M-P and MO-C are affected by the types and oxidation states of noble metals, as well as the target contaminants. Potentials of M or MO (E(M Φ ) or E(MO CB ), defined as work function of the metals or conduction band of the metal oxides) is the determining factor for both charge trapping and charge transfer abilities. The highest photocatalytic activity can be obtained when the E(M Φ ) or E(MO CB ) was kept at the level just beyond the single electron reduction potential of O 2 , such as Ag-P and Ag 2 O-C. Finally, the contaminants-specific photocatalytic activities were related to the different functional reactive species. Findings of this study provide important information for the rational design of M and MO deposited photocatalysts.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
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2021
·
IF 3.171
Xing Zhang,Jingfeng Wu,Junhao Chen,Liang Lu,Lingjun Zhu,Shurong Wang
The catalytic cracking of bio-oil is important to produce aromatic hydrocarbons , which can partially replace gasoline or diesel to greatly reduce carbon emissions from transportation. To further promote the formation of aromatic hydrocarbons, this work studied the effects of the preparation method and the acid strength of Ga 2 O 3 /HZSM-5 on catalytic cracking of the bio-oil distilled fraction systematically. The preparation method of Ga 2 O 3 /HZSM-5 had an important effect on its catalytic activity: the Ga 2 O 3 /HZSM-5 prepared by physical mixing showed the low dispersion of active phases and poor pore structure, resulting in its insufficient activity and severe coke deposition; the Ga 2 O 3 /HZSM-5 prepared by precipitation exhibited the higher activity, while many polycyclic aromatic hydrocarbons unfavorable for the subsequent utilization were in the oil phase; the Ga 2 O 3 /HZSM-5 prepared by impregnation showed the highest activity and 35.5% (mass) selectivity of the oil phase, including 80.3% monocyclic aromatic hydrocarbons and 12.0% polycyclic aromatic hydrocarbons. The Brønsted acidity of Ga 2 O 3 /HZSM-5 decreased with Si/Al ratio, leading to the decline in reactant conversion, oil phase selectivity and quality. Meanwhile, the polymerization between monocyclic aromatic hydrocarbons and oxygenates was promoted to produce many polycyclic aromatic hydrocarbons and even coke, causing catalyst deactivation .
研究领域:
能源化学
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催化材料
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
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2024
·
IF 6.5
Peng Zhang,Fangfang Li,Xuefang Yao,Pengze Zhang,Yukai Wu,Mengmeng Xi,Fanhui Meng,Lihua Kang,Mingyuan Zhu
The GaZrO x solid solution has been recently employed in OX-ZEO bifunctional catalysts for efficient conversion of syngas to light olefins, but it remains challenging to identify the specific contributions of Zr and Ga and to understand the detailed reaction mechanisms due to the structural complexity. To address this complexity and elucidate the active sites over the Zr-Ga oxide system, this study presents a catalyst designed by physical mixing ZrO 2 with different crystalline phases ( m -ZrO 2 & t -ZrO 2 ) and α -Ga 2 O 3 . The physical mixture of m -ZrO 2 and α -Ga 2 O 3 achieves a high CO conversion of 39.1 %, with light olefins selectivity of 87.3% among hydrocarbons after combined with SAPO-34, surpassing the performance of physical mixture of t -ZrO 2 and/or α -Ga 2 O 3 with SAPO-34. Combining the various characterizations and DFT calculations, we have confirmed that m -ZrO 2 site, enriched with oxygen vacancies and surface hydroxyl groups, is essential for CO adsorption and HCOO* intermediate formation, while the α -Ga 2 O 3 site plays a key role in the dissociation of H 2 . Furthermore, the electron transfer from m -ZrO 2 to α -Ga 2 O 3 in their mixture is more efficient than in a physically mixed t -ZrO 2 and α -Ga 2 O 3 . This accelerates the H 2 dissociation and boosts the spillover of hydrogen from α -Ga 2 O 3 to m -ZrO 2 , leading to the formation of more CH 3 O* intermediates and higher light olefins yield when combined with SAPO-34.
研究领域:
催化化学
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材料科学
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计算化学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2020
·
IF 3.83
Fenqi Du,Dongmei Yang,Yue Sun,Yang Jiao,Feng Teng,Haibo Fan
Ultrawide band gap semiconductor materials have attracted considerable attention in recent years owing to their great potential in the photocatalytic field. In this study, Zn-doped Ga 2 O 3 nanofibers with various concentrations were synthesized via electrospinning; they exhibited a superior photocatalytic degradation performance of rhodamine B dye compared to that of undoped Ga 2 O 3 nanofibers. The Zn dopant replaced Ga sites via replacement doping, which could increase the concentration of oxygen vacancies and lead to enhanced photocatalytic properties. When the Zn concentration increased, a Ga 2 O 3 /ZnGa 2 O 4 hybrid structure formed, which could further enhance the photocatalytic performance. The separation of photogenerated carriers due to Zn doping and heterojunctions were the primary causes of the enhanced photocatalytic performance. This study provides experimental data for the fabrication of high-performance photocatalysts based on Ga 2 O 3 nanomaterials .
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
CERAMICS INTERNATIONAL
·
2020
·
IF 3.83
Bo-wen Wang,Bao-hui Chen,Peng-zhao Gao,Hui-hui Chen,Pei Zhang
ZnO based varistors added with minor content of Bi 2 O 3 , Sb 2 O 3 , Co 2 O 3 , SiO 2 , MnO 2 et al. with high voltage gradient, excellent mechanical and thermal properties were fabricated by Ga 2 O 3 doping and using raw ZnO nanoparticles . The compositions and microstructure of the varistors, as well as their electrical, mechanical, and thermal properties were investigated via XRD , XPS, SEM, E-J, C–V, mechanical, and thermal expansion measurements. Also, the mechanism of Ga 2 O 3 addition on the electrical and mechanical properties of the varistors was discussed in detail. Results showed that the added Ga 2 O 3 preferentially occupied the lattice position of ZnO crystal through the formation of a substitutional solid solution (Donor doping), it then occupied the void position through the formation of an interstitial solid solution (Acceptor doping), in which the residual Ga 2 O 3 existed in the grain boundary and served as inversion boundaries. The formation of the substitutional and interstitial solid solutions helped to improve the electrical properties, when Ga 2 O 3 content was 0.40 mol%, values of E 1mA , α, and K were 1235.00 V mm −1 , 46.0, and 1.37, respectively, being due to the small particle size and the related content of donor, acceptor and grain boundary in ZnO grain; The increased content of inversion boundaries stimulated the abnormal growth of ZnO grain, and the formed plate-like grain helped to improve the mechanical properties and thermal expansion coefficient of the varistors, values of σ f , E f , and K IC could reach 147.43 MPa, 213.61 GPa and 2.05 MPa m 1/2 , showing improvements of 25.29%, 47.67%, and 38.51%, respectively, compared with those of ZnO based varistors without Ga 2 O 3 .
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
Molecular Catalysis
·
2017
·
IF 0
Qing Liu,Zebin Yu,Mingjie Li,Yanping Hou,Lei Sun,Li Wang,Zhenbo Peng,Dongmei Chen,Yuxin Liu
A novel Ag/AgBr/Ga 2 O 3 composite with heterojunction microstructure was synthesized by using chemical deposition followed by UV reduction method. High resolution transmission electron microscopy showed that Ga 2 O 3 microparticles were tightly attached with Ag/AgBr to form a heterojunction. UV–vis diffuse reflectance spectra revealed that light response capability of Ga 2 O 3 was enhanced significantly when combined with Ag/AgBr. The degradation efficiency of methyl orange within 30 min under UV light irradiation with Ag/AgBr/Ga 2 O 3 , Ag/AgBr and Ga 2 O 3 were 89%, 74% and 48%, respectively. Ag/AgBr/Ga 2 O 3 not only showed excellent photocatalytic activity under UV light, but also exhibited efficient photocatalysis capacity under visible light. Furthermore, the mechanism of charge separation in the heterojunction under UV light irradiation was proposed.
研究领域:
材料科学
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化学
·
环境科学
✓ 已验证
产品关联
DOI
JOURNAL OF PHYSICS D-APPLIED PHYSICS
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2023
·Vol. 57
·期 1
·015104
·
IF 3.4
Songhao Wu,Zichun Liu,Han Yang,Yeliang Wang
As a simple and effective method for improving the crystalline quality of epitaxial Ga2O3 film, post-thermal treatment has been identified as a competitive process involving crystal reconstruction accompanied by defect formation. In this study, β-Ga2O3 films grown on a c-sapphire substrate using low-pressure chemical vapor deposition were subjected to thermal treatment at 1000 °C in air for various duration to investigate the effects of treatment time on the films. The full width at half maximum (FWHM) of x-ray rocking curves initially decreased from 1.62° to 0.98° with increasing treatment time up to 5 h, indicating improved crystallinity. This improvement is likely a result of the reduced angle between Ga2O3 grains and the reconstructed Ga2O3 lattice, oriented towards the (−201) plane due to the thermal treatment, as observed in the transmission electron microscope and electron back-scattering diffraction results. However, under 7 h of treatment, the crystallinity of Ga2O3 degraded, as evidenced by an increased FWHM, as well as by x-ray photoelectron spectroscopy, photoluminescence, and time-of-flight secondary ion mass spectrometry results. This degradation can be attributed to the presence of massive oxygen vacancies and the substitutional incorporation of nitrogen into oxygen sites (NO), resulting in defects.
研究领域:
材料科学
·
晶体生长
✓ 已验证
产品关联
DOI
高影响因子
CATALYSIS COMMUNICATIONS
·
2018
·
IF 3.463
Qiaoqi Li,Yujie Zhang,Lili Zhang,Jun Xia,Xiaoyan Liu,Lei Hu,Fei Wang,Xiaozhong Chu,Pusu Zhao,Jingzhou Yin,Dingfeng Yang
Gallium oxide semiconductors have been developed as effective photocatalysts for water splitting driven by UV light irradiation, but there is no relevant study for the CO 2 photoreduction application. Herein, we report the first investigation of β -Ga 2 O 3 applying to photocatalytic CO 2 reduction under visible light irradiation by doping transition metal ions ( M = V, Cr, Mn, Fe, Co, Ni and Cu) onto the framework. Using sol-gel method, a series of transition metal ions incorporated β -Ga 2 O 3 have been successfully obtained, in which the transition metal substitution content is 2 mol%. The β -Ga 2 O 3 : M photocatalysts are characterized completely by diverse tests (e.g., XRD, XPS, UV–Vis DRS, SEM). The effective replacement of Ga 3+ ion by M ions significantly expands the scope of spectral response from UV light to visible light, and Fe 3+ , Co 2+ , Ni 2+ significantly enhance the photocatalytic activity under visible light irradiation. In these cases, CO and H 2 are evolved as the reduction products from CO 2 and H + by the generated electrons, respectively. Among these effective catalysts we prepared, β -Ga 2 O 3 :Ni exhibits the most substantial CO formation rate of 14.3 μmol/h at 30 °C, and the selectivity for CO evolution exceeds 60.9%. Furthermore, the CO formation rate increases to 24.6 μ mol/h after loading of Ag as the co-catalyst. The stability of the Ag/ β -Ga 2 O 3 :Ni are verified after five cycle of CO 2 photoreduction under visible light.
研究领域:
材料科学
·
环境科学
·
化学工程
✓ 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）