Journal of Physical Chemistry C
·
2018
·
IF 4.484
Xing Xu,Lei Lai,Tao Zeng,Yan Yu,Zhiqiao He,Jianmeng Chen,Shuang Song
The exploration of low-cost, high-performance, and stable photocatalysts for the highly efficient conversion and storage of solar energy in hydrogen is of great importance. This study presents a novel pyridine-type carbonitrides (CN)-modified surface-disordered C-doped TiO2 (PCN/CTiO2@TiO2–x) catalyst used for photocatalytic H2 evolution from water. The employed preparation method of hydrolysis–calcination has the advantages of low-cost raw materials and easy scale-up. The optimized PCN/CTiO2@TiO2–x exhibited an impressive hydrogen evolution rate of ∼3743 μmol h–1 g–1 under simulated solar light (AM 1.5) and remained stable after five cycles. The maximal quantum efficiency reached 37.5% at 370 nm and 7.0% at 400 nm, which was superior or comparable to several reported relevant TiO2-based catalysts. Benefiting from the pyridine-type CN modification, disordered surface layer (TiO2–x), and increased oxygen vacancies/Ti3+ species, the photogenerated electrons moved rapidly from the visible-response C-doped TiO2 to CN to participate in the photoreduction reaction, which led to a marked improvement in the catalytic activity.
研究领域:
材料科学
·
能源化学
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2016
·
IF 6.333
Xiaolei Jiang,Huayun Xu,Hongzhi Mao,Jian Yang,Yitai Qian
Disordered surface of anode materials accompanied by oxygen vacancies , has been developed as an efficient strategy to promote their charge-transfer kinetics and then improve their electrochemical properties . It is rarely explored for cathode materials before. Here, LiTi 2- x Mn x (PO 4- y ) 3 nanoparticles with a disordered surface and oxygen vacancies , are synthesized by a hydrothermal method following with an annealing in Ar/H 2 . Their disordered surface and heteroatom doping by reduced Mn/Ti species, have been supported by HRTEM images, XPS and EDS spectra. After 120 cycles at 0.2 C, these nanoparticles still deliver a capacity of 127 mAh g −1 , much higher than the product without any doping, and that without a disordered surface. Even after 500 cycles, the capacity is still at 101 mAh g −1 for 5 C or at 71 mAh g −1 for 20 C. These results could be attributed to the reduced charge-transfer resistance caused by disordered surface, and the enhanced lithium-diffusion induced by doping.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
ACS Omega
·
2019
·
IF 2.584
Guanghui Li,Jiyang Xie,Jing Wang,Lei Xia,Yong Li,Wanbiao Hu
Lattice disorder has emerged as a novel strategy to realize visible-light photocatalytic activity, but many existing studies often involved reduction states simultaneously. Photocatalysts based on only the lattice disorder but without the reduction states are still quite lacking and challenging. To this end, we explored a new type of lattice disorder in terms of the surface atom nonstoichiometry strategy in BaTiO3. Well-dispersed tetragonal BaTiO3 nanocrystals with a uniform size (∼20 nm) and cuboid morphology were hydrothermally synthesized through controlling over t-butylamine and oleic acid. HRTEM coupled with structural evolution analysis reveals the existence of a Ti-rich layer on BaTiO3 nanocrystals with surface atom disorder, which gives an overall Ti/Ba ratio of 1.50:1. This is mainly dominated by the oriented adsorption between oleic acid and surface Ba2+ of the nucleus during solution reaction. Such a surface disorder and Ti-rich nonstoichiometry effect could facilitate the enhanced visible-light absorption with a wavelength span of 400–700 nm that enables the superior visible-light photocatalytic property, which is not subject to the reduction states. This work demonstrates a first white material presenting a new type of lattice disorder that would be helpful for a wide range of photocatalyst explorations.
研究领域:
材料科学
·
光催化
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry A
·
2019
·Vol. 7
·期 8
·3863-3873
·
IF 10.733
Kewei Yang,Xiaoyu Chen,Zhenhuan Zheng,Jiaqi Wan,Miao Feng,Yan Yu
TiO2 nanocrystal (NC)-based photoreversible color switching (PCS) materials, which are capable of actively responding to external light, have significant potential for use in printable rewritable paper in the creation of sustainable technologies. Reductive TiO2 NCs with high hole-scavenging capabilities can be obtained by surface disorder or lattice distortion, but achieving an optimum balance between them is still a great challenge to enable simultaneous retention of the photoreduction performance and visible light catalytic ability of the TiO2 NCs. Here, we demonstrated solvent-controlled synthesis of interstitial Sn2+-doped TiO2 NCs and investigated the effects of solvent-induced surface disorder and doping-induced lattice distortion on the PCS properties of the TiO2 NCs. The midgap state produced by surface disorder combines with the energy level produced by the interstitial Sn2+ dopants in TiO2 NCs to become the main center for photogenerated electron transfer. Thus, efficient PCS was achieved, with the number of switching cycles greatly increased. The ethylene glycol-synthesized TiO2 NCs with a Sn2+-doping concentration of ca. 3% are the most favorable catalyst for achieving PCS performance. The process of PCS can be repeated 48 times without any rest. The results of this work suggest an approach to the design and preparation of PCS materials that exhibit excellent scalability and outstanding reversible performance by using colloidal NCs with optimized surface composition, lattice structure, and particle size as key-functional photocatalysts.
研究领域:
材料科学
·
光催化
✓ 已验证
产品关联
DOI
高影响因子
Nano Research
·
2021
·Vol. 15
·期 2
·996-1002
·
IF 8.897
Ha Enna,Ruan Shuhong,Li Danyang,Zhu Yuanmin,Chen Yanping,Qiu Jiangyuan,Chen Zhaohui,Xu Tingting,Su Jingyun,Wang Luyang,Hu Junqing
Metal chalcogenide solid solution, especially ZnCdS, has been intensively investigated in photocatalytic H 2 generation due to their cost-effective synthetic procedure and adjustable band structures. In this work, we report on the defect engineering of ZnCdS with surface disorder layer by simple room temperature Li-ethylenediamine (Li-EDA) treatment. Experimental results confirm the formation of unusual Zn and S dual vacancies, where rich S vacancies (V S ) served as electron trapping sites, meanwhile Zn vacancies (V Zn ) served as hole trapping sites. The refined structure significantly facilitates the photo charge carrier transfer and improves photocatalytic properties of ZnCdS. The disordered ZnCdS shows a highest photocatalytic H 2 production rate of 33.6 mmol·g −1 ·h −1 under visible light with superior photocatalytic stabilities, which is 7.3 times higher than pristine ZnCdS and 7 times of Pt (1 wt.%) loaded ZnCdS.
研究领域:
材料科学
·
化学
·
光催化
·
可再生能源
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）