ACS Applied Materials & Interfaces
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2021
·
IF 9.229
Yu Fang,Yang Cao,Bihui Tan,Qianlin Chen
Solar energy can be used as “green” energy by photocatalysis for the nitrogen fixation under the atmospheric conditions compared with the traditional energy-intensive industrial production of ammonia. However, the complex kinetics and high reaction barriers greatly hinder the development of the photocatalytic N2 reduction reaction. Herein, a BiOBr/MXene-Ti3C2 composite catalyst is prepared by the simple electrostatic adsorption and self-assembly method. The as-prepared 10 wt % BiOBr/Ti3C2 exhibits the best performance for N2 fixation to NH3 by photocatalysis. The evolution rate of NH3 is up to 234.6 μmol·g–1·h–1, which is approximately 48.8 times and 52.4 times higher than those of pure BiOBr and Ti3C2, respectively. It is found that the designed double vacancies of oxygen and titanium for BiOBr/Ti3C2 composites, with the availability of localized electrons, have the ability to adsorb and activate N2, which can be efficiently reduced to NH3 by the interfacial electrons transferred from the excited BiOBr/Ti3C2 composite. In addition, the results of in situ Fourier transform infrared show the generation of NxHy species by the continuous protonation processes. Moreover, titanium vacancy (VTi) induces a strong absorption energy for nitrogen atoms on the surface of BiOBr/Ti3C2 according to the density functional theory calculations. In particular, the P-electron feedback caused by VTi could effectively promote the weakening of the N≡N triple bond and elongate the N2 bond length by ∼31.6%. This work might provide new insights into the synergistic effect of double defects and inspiration for the rational design of catalysts by defect engineering in the field of catalytic synthesis of ammonia.
研究领域:
材料科学
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催化化学
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DOI
高影响因子
CHEMICAL PHYSICS LETTERS
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2018
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IF 1.686
Zi-Chang Wu,Yi Lu,Yong Wang,Yuan-Zhou Li,Li He,Xiu Cheng,Wei Geng,Jie Ying,Gang-Gang Chang
A hierarchical structured TiO 2 @C photocatalyst has been fabricated by using P25 as model nano-photocatalyst and dictyophora indusiata as a natural hierarchical template, which showed significantly higher photocatalytic performance in comparison with P25 and M-TiO 2 @C. The enhanced catalytic properties can be mainly ascribed to the formation of titanium vacancy and promoted diffusion and transport of substrate molecule benefited from the hierarchical structure.
研究领域:
材料科学
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环境科学
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DOI
高影响因子
Nature Communications
·
2020
·Vol. 11
·期 1
·1-9
·
IF 12.121
Pan Lun,Ai Minhua,Huang Chenyu,Yin Li,Liu Xiang,Zhang Rongrong,Wang Songbo,Jiang Zheng,Zhang Xiangwen,Zou Ji-Jun,Mi Wenbo
Photocatalysis has been regarded as a promising strategy for hydrogen production and high-value-added chemicals synthesis, in which the activity of photocatalyst depends significantly on their electronic structures, however the effect of electron spin polarization has been rarely considered. Here we report a controllable method to manipulate its electron spin polarization by tuning the concentration of Ti vacancies. The characterizations confirm the emergence of spatial spin polarization among Ti-defected TiO 2 , which promotes the efficiency of charge separation and surface reaction via the parallel alignment of electron spin orientation. Specifically, Ti 0.936 O 2 , possessing intensive spin polarization, performs 20-fold increased photocatalytic hydrogen evolution and 8-fold increased phenol photodegradation rates, compared with stoichiometric TiO 2 . Notably, we further observed the positive effect of external magnetic fields on photocatalytic activity of spin-polarized TiO 2 , attributed to the enhanced electron-spin parallel alignment. This work may create the opportunity for tailoring the spin-dependent electronic structures in metal oxides.
研究领域:
材料科学
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物理化学
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产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2024
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IF 20.2
Yue Xin,Hongjie Wang,Hao Xue,Qiang Li,Huanxin Li,Yue Zhang,Yanzhi Dong,Haijiao Xie,Yiyang Ma
Cobalt atoms anchored on Ti 3 C 2 -based MXene (i.e., Co-SA/MXene) have been successfully endowed with exceptional catalytic performance for the elimination of aqueous micropollutants. Herein, we firstly proposed a coupling method of etching-exfoliation-reduction to enrich titanium vacancies. The as-synthesized Co-SA/MXene exhibited a superior removal efficiency of ranitidine of 100 %, and the corresponding reaction kinetics constant (μmol/s•g) was 1.11–6643.53 times higher than the state-of-the-art for ranitidine degradation. The introduction of abundant titanium vacancies enabled a long-lasting life via an accelerated valence cycling of Co(II) and Co(III), and also effectively inhibited toxic Co 2 + leaching. DFT revealed that O II /O III dual-atoms were more suitable for PMS adsorbing while offering stronger adsorption energy, and further offered a new insight into the PMS activation mechanism for 1 O 2 selected generation. This work revealed that oxidation behavior of ranitidine and established an attractive water treatment technique for the rapid removal of aqueous micropollutants.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
CHEMISTRY-A EUROPEAN JOURNAL
·
2021
·Vol. 27
·期 57
·14202-14208
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IF 5.236
Yan-Xiang Zhang,Si-Ming Wu,Ge Tian,Xiao-Fang Zhao,Li-Ying Wang,Yi-Xia Yin,Lu Wu,Qian-Ni Li,Yue-Xing Zhang,Jin-Song Wu,Christoph Janiak,Kenneth I. Ozoemena,Menny Shalom,Xiao-Yu Yang
Graphical Erosion of corrosion : TiO 2 nanofibers with rich Ti vacancies have been designed by a facile controllable calcination approach. They exhibit efficient charge transfer and resistance to corrosion by seawater owing to a unidirectional electron trap and superior H + adsorption; which contribute to excellent activity and long-time stability in photodriven seawater splitting. This study could provide a promising strategy for the design of efficient semiconductors in marine applications. Photodriven seawater splitting is considered to be one of the most promising techniques for sustainable hydrogen production. However, the high salinity of seawater would deactivate catalysts and consume the photogenerated carriers. Metal vacancies in metal oxide semiconductors are critical to directed electron transfer and high salinity resistance; they are thus desirable but remain a challenge. We demonstrate a facile controllable calcination approach to synthesize TiO 2 nanofibers with rich Ti vacancies with excellent photo/electro performances and long-time stability in photodriven seawater splitting, including photocatalysis and photo-electrocatalysis. Experimental measurements and theoretical calculations reveal the formation of titanium vacancies, as well as unidirectional electron trap and superior H + adsorption ability for efficient charge transfer and resistance to corrosion by seawater. Therefore, atomic-/nanoscale characteristics and mechanism have been proposed to clarify the generation of titanium vacancies and the corresponding interfacial electron transfer.
研究领域:
材料科学
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能源化学
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环境科学
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产品关联
DOI
PubMed
高影响因子
Nano Energy
·
2023
·
IF 17.6
Chao Liu,Caichao Ye,Yunyan Wu,Yifan Liu,Zhihang Liu,Zhaotian Chen,Renzhi Ma,Nobuyuki Sakai,Liang Xue,Jingwen Sun,Wenyao Zhang,Wenqing Zhang,Xin Wang,Takayoshi Sasaki,Pan Xiong,Junwu Zhu
Water evaporation-induced electricity generation , as an emerging energy harvesting technology, has recently attracted extensive attention owing to its ability to harvest electricity directly from the natural water evaporation process. However, the crucial issue that has restricted its practical applications is the low power density and conversion efficiency presented thus far, which generally originated from the weak water-solid interaction between evaporation-induced water flow and nanostructured materials . Exploration of a regulatory approach that can enhance water-solid interaction at an atomic level is highly demanded. Herein, we propose the Ti vacancy engineering at the atomic scale in two-dimensional (2D) unilamellar titanium oxide (Ti 1 − δ O 2 ) nanosheets for efficient water evaporation-induced electricity generation. 2D Ti 0.87 O 2 and Ti 0.91 O 2 nanosheets with precisely controlled concentrations of Ti atomic vacancies are rationally designed. The water flow passes through the 2D gallery of nanosheets while the Ti atomic vacancies can effectively enhance the water-solid interaction between Ti 1 − δ O 2 nanosheets and water flow during the water evaporation process for electricity generation. As a result, a stable open-circuit voltage of ∼1.32 V for the hydrovoltaic device made of Ti 0.87 O 2 nanosheets can be maintained for more than 250 h, outperforming those for the commercial TiO 2 and Ti 0.91 O 2 nanosheets. This work indicates a promising way to utilize defective 2D materials for hydrovoltaic technology.
研究领域:
材料科学
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纳米技术
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能量收集
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表面科学
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产品关联
DOI
高影响因子
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