JOURNAL OF CATALYSIS
·
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
·
材料科学
·
计算化学
✓ 已验证
产品关联
DOI
高影响因子
Surfaces and Interfaces
·
2025
·
IF 6.3
Chunlin Wen,Zhenhua Tang,Tingsu Liu,Fan Qiu,Yan-Ping Jiang,Xin-Gui Tang,Yi-Chun Zhou,Xiangjun Xing,Ju Gao
Recently, Ga 2 O 3 -based devices with a wide bandgap have gained great attention in power semiconductor devices. However, Ga 2 O 3 -based devices with the substable crystalline phase and high performances need be further developed and discussed. In this work, the α-Ga 2 O 3 thin films and GQDs/α-Ga 2 O 3 heterojunctions were prepared by magnetron sputtering on the transparent FTO substrates with a buffer TiO 2 layer. And, the good self-powered deep-ultraviolet photodetection performance and mechanisms were discussed in the GQDs/α-Ga 2 O 3 /α-TiO 2 /FTO devices: its responsivity to 254 nm UV light can reach 1.72 mA/W at a bias voltage of 0 V, a normalized detection rate of 1.7 × 10 10 Jones and the light-to-dark current ratio (PDCR) of ∼1 were achieved due to the change of heterojunction energy band type from II to I. Moreover, the good self-powered deep UV photodetection for GQDs/α-Ga 2 O 3 /α-TiO 2 /FTO devices were demonstrated: a PDCR of 1.1 × 10 3 , a self-powered responsivity (R) improved by a factor of 5 to 8.7 mA/W, the rise time (τ r )/fall time (τ f ) of 86/39 ms, and a normalized detectivity (D*) with an improved magnitude of 1.3 to 2.3 × 10 11 Jones were achieved by constructing GQDs/α-Ga 2 O 3 heterojunctions on the outer surface of α-Ga 2 O 3 thin film. These results can provide a reference for the future development of Ga 2 O 3 thin film devices.
研究领域:
材料科学
·
光电子学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Electronic Materials
·
2023
·
IF 4.7
Zhiyuan Chen,Peipei Han,Wenhui Chen,Zhi Wan,Jizhou Yang,Zhigang Liu,Peng Hu,Feng Teng,Haibo Fan
In recent years, Ga2O3 flexible solar-blind ultraviolet photodetectors (UVPDs) are gradually becoming the focus of research and the industry because of their excellent wearability, low manufacturing cost, portability, large area compatibility, and high scalability. However, the crystallization temperature required for high-quality α-phase Ga2O3 films exceeds the heat resistance of most flexible materials, so the growth of Ga2O3 films on flexible substrates is a very big challenge. In this study, a highly ordered α-Ga2O3 nanorod array and flexible solar-blind UV PDs with excellent performance were successfully prepared on a flexible titanium (Ti) substrate at 500 °C by a simple water bath heating method. When irradiated by 254 nm ultraviolet light, the α-phase Ga2O3 flexible photodetector exhibits an excellent self-power optical response at 0 V bias and exhibits excellent photoelectric performance with a responsivity of 15.3 mA/W, a fast rise and fall time of 0.104 and 0.077 s, a photocurrent density of 45.7 μA/cm2, and a high detectivity of 13.8 × 109 Jones. Bending and repeating experiments demonstrated that the detector had high stability. This study provides a simpler and less expensive method for the preparation of flexible self-powered α-Ga2O3 solar-blind UV photodetectors.
研究领域:
材料科学
·
光电子学
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Communications
·
2024
·
IF 3.7
Junliang Fan,Li Xiao,Yuantao Qin,Hao Yan,Xiaolin Qu,Zhenzhen Li,Hengxiang Gong
There is little research on α-Ga 2 O 3 single crystal film because it is a metastable phase of Ga 2 O 3 crystal and difficult for controllable fabrication. In this paper, highly crystallized Ga 2 O 3 thin films of poly-crystalline, α-Ga 2 O 3 and β-Ga 2 O 3 were prepared by modulating the growth temperature from 400 °C to 700 °C by mist-assisted CVD (Mist CVD) method. The results show that films grown at 525 °C owes the best crystalline quality of α-Ga 2 O 3 film. To further improve the crystallinity of α-Ga 2 O 3 thin film, a systematic simulation revealing the distribution changes of aerosol particle size, flow field, and temperature gradient in the reaction chamber were explored. The optimal growth region C with uniform particle size, well-distribute temperature gradient and stable flow field is determined. Meanwhile, the experimental results of α-Ga 2 O 3 thin films grown at different positions in the reaction chamber was proved to consistent with the simulation results. Furthermore, the optimal single crystallized α-Ga 2 O 3 thin films with smooth surface morphology and optical property were obtained. The PL spectrum operated at room temperature show the α-Ga 2 O 3 film with low defect density and high crystalline quality. It shows that the single crystallized α-Ga 2 O 3 is orientated grown on sapphire substrate with epitaxial relationship of α-Ga 2 O 3 (0006)//c-Al 2 O 3 (0006). Although, slight lattice mismatch is observed on the selected area electron diffraction pattern of the interface between sapphire and α-Ga 2 O 3 film, it is ideal for further application in devices. This work reveals the key point for α-Ga 2 O 3 single crystal film growth by mist CVD is to construct a steady and orderly environment through controlling aerosol particle state.
研究领域:
材料科学
·
物理学
✓ 已验证
DOI
高影响因子
CRYSTENGCOMM
·
2022
·Vol. 24
·期 9
·1789-1794
·
IF 3.756
Yanan Zhang,Shujie Jiao,Junhua Zhang,Shuo Liu,Dongbo Wang,Shiyong Gao,Jinzhong Wang
A GaOOH/Ga2O3 heterojunction was obtained by a one-step annealing treatment at a certain temperature. The solar blind photoresponse performance of the GaOOH/Ga2O3 heterojunction was characterized through photoelectrochemical detectors, providing a simple and effective method for pure solar-blind ultraviolet detection. The results showed that the maximum responsivity of the α-GaOOH/α-Ga2O3 heterojunction detector is 0.29 mA W−1 at 250 nm, which is 370% and 145% higher than that of the α-GaOOH and α-Ga2O3 detectors, respectively. The calculated solar-blind/visible detection ratio and light-to-dark current ratio of the detector are also significantly improved compared with the α-Ga2O3 and α-GaOOH detectors, reflecting better pure solar-blind ultraviolet detection performance. The photoresponse mechanism has been studied systemically.
研究领域:
材料科学
·
光电子学
✓ 已验证
产品关联
DOI
高影响因子
Optical Materials Express
·
2024
·Vol. 14
·期 11
·2728-2739
·
IF 2.8
Chenrui Zhang,You Wu,Yanbin Li,Yanbin Li,Di Xiao,Yuanyuan Zheng,Yuanyuan Zheng,Zhitai Jia,Le Zhang,Le Zhang
As a wide-bandgap semiconductor material, α-Ga2O3 has great potential in high-power devices and deep ultraviolet photodetectors. However, for α-Ga2O3 growth by mist chemical vapor deposition (mist-CVD), the clustering of mist flow often appears, resulting in poor crystallinity and rough surface of the α-Ga2O3 films. In this study, we established a homemade mist-CVD system with a heating structure and a cuboid chamber. The effects of the pressure difference between the inlet and outlet of the reaction chamber as well as the growth temperature on α-Ga2O3 film growth were systematically investigated. High-quality α-Ga2O3 thin films with a smooth surface were prepared at 450 °C under a 80 Pa pressure difference due to the weakened clustering effect of mist flow. The surface root-mean-square (RMS) roughness of the α-Ga2O3 films was as low as 1.32 nm, and the growth rate could reach 26.9 nm/min. The transmittance was higher than 80% in the near-ultraviolet to visible light region, and the optical band gap was determined to be 5.23 eV.
研究领域:
材料科学
·
半导体物理
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）