Catalysis Science & Technology
·
2020
·Vol. 10
·期 11
·3709-3719
·
IF 5.721
Chengwei Qiu,Jinjin Lin,Jinni Shen,Dan Liu,Zizhong Zhang,Huaxiang Lin,Xuxu Wang
Anatase/rutile TiO2 heterophase junction composites have been documented to have much higher photocatalytic activity than single phase TiO2 (nude anatase or nude rutile) for various chemical reactions, including hydrogen production from methanol–water solution and pollution degradation. Further improving the photocatalytic performance of heterophase junction photocatalysts is a subject worth studying in both theory and practice. Based on the concept of junction interface regulation and our previous findings, we embedded Ni12P5 nanoparticles at the interface between anatase (A) and rutile (R) TiO2 by a multi-step preparation method to obtain an A/Ni12P5/R composite with a sandwich-like structure. It was found that loading Ni12P5 on the outside surface of anatase TiO2 (Ni12P5/A), rutile TiO2 (Ni12P5/R), P25 TiO2 (Ni12P5/P25), and A/R composite (Ni12P5/A/R) leads to a decrease in the photocatalytic activity; however, interestingly, the A/Ni12P5/R sample showed higher photocatalytic activity than the other samples of loaded or unloaded Ni12P5, although the loaded Ni12P5 in the latter case is inaccessible to the reactant molecules. This abnormal phenomenon can be attributed to two main reasons. (i) Ni12P5 as a metal-like material has a higher work function than anatase and rutile, which leads to the formation of Schottky junctions at the interface between the two intimately contacted phases. (ii) When Ni12P5 is located on the outside surface, the Schottky junction is unfavorable for the transfer of photogenerated electrons from TiO2 to Ni12P5. However, when Ni12P5 is sandwiched between A and R, the formation of a reverse tandem Schottky junction can facilitate the directed transfer of photogenerated electrons from R phase to A phase. This work again verifies that photocatalytic activity can be regulated and controlled by introducing metal and metal-like particles within the junction of a metal/semiconductor interface or even on a semiconductor/semiconductor interface. Our findings not only provide a novel usage of Ni12P5 as a co-photocatalyst but also deepens the understanding of the Schottky effect on the photocatalytic process.
研究领域:
材料科学
·
光催化
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Xianping Ye,Jian Wu,Fenghua Chen
Fabrication of low-cost, stable and highly efficient catalysts for clean energy and environmental control applications is an urgent task. In this work, we have successfully synthesized a multifunctional two-dimensional rare earth-based LaOCl@hcp-Ni heterostructure via a simple one-pot method. Here, the semiconductor LaOCl nanoparticles were well deposited on the metastable metal hcp-Ni, and the hexagonal close-packed structure of hcp-Ni matched the layered-structure LaOCl to form a highly active LaOCl@hcp-Ni Schottky catalyst. Furthermore, LaOCl@hcp-Ni were tested for Photoelectrochemical (PEC) oxygen evolution reaction (OER) in alkaline media and the photocatalytic (PC) degradation of Rhodamine B (RhB) in aqueous solution. LaOCl@hcp-Ni shows excellent PEC-OER catalytic activity and RhB degradation performance under artificial simulated sunlight. This enhancement of PEC and PC performance is due to the Schottky interface constructed by the coupling of hcp-Ni and LaOCl, which generates an interface electric field to effectively promote the transfer of photogenerated electrons from the semiconductor LaOCl to the metal hcp-Ni through the interface. Thus, energy band gap of LaOCl with oxygen defects is adjusted to the visible light region and their valence state of La is lowered, realizing high-efficiency visible light catalytic activity. Thus, it would be a potential rare earth-based Schottky catalyst, which can be used for the PEC oxygen evolution and the PC degradation of organic pollutants.
研究领域:
材料科学
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环境科学
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
DALTON TRANSACTIONS
·
2023
·Vol. 52
·期 28
·9721-9730
·
IF 4
Xinyu Liu,Lan Wang,Shan Ji,Vladimir Linkov,Qianqian Fu,Zhichao Li,Hui Wang
Due to their low cost and excellent electrocatalytic performance, nickel-based hydroxides are widely used as hydrogen evolution catalysts for large-scale hydrogen production by water electrolysis. In this study, a heterostructured composite with improved electron transport and modulated electron surface density was prepared by combining Ni(OH)2 with two-dimensional layered Ti3C2Tx (Ti3C2Tx-MXene). Ni(OH)2 nanosheets were formed on nickel foam (NF) substrates using acid etching, followed by the longitudinal growth of negatively charged Ti3C2Tx-MXene on positively charged Ni(OH)2/NF via electrophoretic deposition. The resulting structure facilitates spontaneous electron transfer from Ti3C2Tx-MXene to Ni(OH)2/NF by means of the Mott–Schottky heterostructure effect and establishes a continuous electron transport path which effectively increases the concentration of active sites, improving hydrogen evolution during water electrolysis. The obtained electrode is characterized by an HER overpotential of 66 mV (vs. RHE) and a Tafel slope of +105 mV dec−1 at a current density of 10 mA cm−2, combined with good electrochemical stability.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CARBON
·
2025
·
IF 11.6
Shijie Zhang,Jiajun Zheng,Changpeng Lv,Di Lan,Qingfeng Tian,Zhenguo Gao,Siyuan Zhang,Zhiwei Zhao,Shichang Cai,Guanglei Wu
The incorporation of a built-in electric field (BIEF) in nanocomposites has been well-recognized as a mainstream approach for enhancing the interface polarization. Nevertheless, the effect of sole BIEF on the dielectric loss is insufficient, and its combination with other loss mechanisms is necessary to achieve optimized electromagnetic wave performances. Herein, the nano carbon hybrids with Cu–ZnO Schottky BIEF with abundant defects were designed and derived through an etching and ligand exchange process, which involved the conversion of CuZn-BTC into a bimetallic ZIF structure. The conversion process effectively controlled the morphologies and induced a significant density of defects in the derivatives, thereby imparting diverse electrical conductivities and dielectric properties to the composites. This was achieved through the modulation of the cell volumes of Cu–ZnO polycrystals, the oxygen vacancies in ZnO, the nitrogen defects within the carbon matrix, and the creation of extensive heterointerfaces. The analysis indicated that the polarization relaxation dominated the dielectric loss. When the H 2 O/methanol in etching solvent was 3:7, the derived composite (S2) exhibited well matched impedance, and synergistic enhancement of BIEF effect and defect-induced polarization. Attributed to these merits, S2 achieved an ultra-wide effective absorption bandwidth (EAB) of 7.12 GHz at 2.3 mm. Notably, the EAB exceeded 6.0 GHz when the matched thickness ranged from 1.8 mm to 2.7 mm. This study can introduce a novel approach for the development of advanced absorbers based on the Schottky BIEF.
研究领域:
材料科学
·
电磁学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
ACS Catalysis
·
2019
·
IF 12.221
Xingxing Li,Yu Pan,Hong Yi,Jingcheng Hu,Dali Yang,Fengzhi Lv,Wendian Li,Jinping Zhou,Xiaojun Wu,Aiwen Lei,Lina Zhang
Improving the selectivity and retaining the efficiency of catalysts are essential for industrial processes and remain a great challenge. Herein, we developed a facile route to synthesize Pd nanocubes (NCs) using Eosin Y as the photosensitizer under visible light. Subsequently, Pd NCs were uniformly loaded on N-doped carbon nanofibrous microspheres (NCMs) from carbonated chitin microspheres. This Pd NCs@NCM exhibited high reactivity and selectivity in alkyne semihydrogenation. For example, the hydrogenations of phenylacetylene to styrene and of 3-phenyl-2-propyn-1-ol to (Z)-cinnamyl alcohol were 12.9 and 18.3 times faster with Pd NCs@NCM than with Lindlar catalyst. According to the Mott–Schottky effect, loading of Pd NCs on N-doped carbon constructed a rectifying contact and decreased the electron density of Pd NCs. Density functional theory (DFT) calculations suggested that the high concentration of holes doped in Pd NCs weakened the interaction of alkenes on the Pd (100) facet and prevented further hydrogenation for a long time; this period of durable time is very helpful in chemical manufacturing. Thus, Pd NCs@NCM maintained both high reactivity and selectivity in comparison with surface-modified catalysts. This work provides an alternative strategy to design Mott–Schottky catalysts for selective hydrogenation reactions.
研究领域:
化学工程
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材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2017
·
IF 9.446
Hongqing Gao,Peng Zhang,Jiangtao Zhao,Yongshang Zhang,Junhua Hu,Guosheng Shao
Direct evidence of plasmon for enhanced H 2 production is observed in photocatalytic water reduction by using TiO 2 /WO 3 electrospun nanofibers decorated with Au nanoparticles. The H 2 production rate of the as-prepared composite nanofibers was greatly enhanced compared with pure TiO 2 nanofibers (S0) and TiO 2 /WO 3 nanofibers (S1). The enhanced activities were mainly attributed to the Schottky effect and Z-scheme photosynthetic heterojunction system, in this system, WO 3 as a hole collector and Au as an electron collector, promoting effective charge separation. More importantly, Surface Plasmon Resonance (SPR) effect of Au further promoted charge separation and absorption of visible light. On the basis of the Z-scheme photosynthetic heterojunction system, the synergistic effect of Schottky and SPR effect further improve the performance of photocatalytic H 2 production, which were directly evidenced by photocurrent, electrochemical impedance spectroscopy (EIS) and ultraviolet Photoelectron Spectrometer (UPS) analysis. Besides, the synthesis route delivered three-dimensional sheets on the basis of interwoven nanofibrous networks, which can be readily recycled for the circular application of a potent photocatalyst system.
研究领域:
材料科学
·
光催化
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2019
·
IF 14.229
Jiashi Wang,Qinhong Wei,Qingxiang Ma,Zhongya Guo,Fangfang Qin,Zinfer R. Ismagilov,Wenzhong Shen
At present, the increasing consumption of fossil fuels as well as the expanding of more effective avenues to prepare carbon materials have inspired scholars' confidence to seek for alternative carbon sources. To address this issue, a N-doped graphene shell encapsulated metallic Co (Co@NGs) catalyst was fabricated using glucose and melamine as carbon source and nitrogen source via carbonization and employed for 5-hydroxylmethylfurfural (HMF) hydrogenation to produce 2,5-dimethylfuran (DMF) biofuel. Here, the prepared Co@NGs catalyst which possessed striking Mott-Schottky effect presented strong electronic interaction at the interface of surface metallic Co and doped N, leading to the electron transfer from metallic Co to doped N on carbon substrate. Experimental results indicated that the decreased electron density of metallic Co was more conductive to selective catalytic hydrogenation of HMF to form DMF. More importantly, the catalytic activity of the Mott-Schottky-type Co@NGs catalyst could be regulated by adjusting the nitrogen content. That is, the high nitrogen content increased the work function of Co@NGs and thus the enhanced rectifying response at the interface by which to enhance the catalytic performance. The best Co@NGs catalyst exhibited both high HMF conversion (close to 100 %) and DMF selectivity (94.7 %), much better than those of conventional N-doped carbon supported Co catalysts.
研究领域:
材料科学
·
催化化学
·
可再生能源
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2023
·
IF 9.9
Jing Jiang,Wei Wei,Zhen Ren,Yang Luo,Xinzhi Wang,Ying Xu,Mingming Chang,Lunhong Ai
Developing efficient catalysts for the dehydrogenation of ammonia borane (AB) is important for the safe storage and controlled release of hydrogen, but it is a challenging task. In this study, we designed a robust Ru-Co 3 O 4 catalyst using the Mott-Schottky effect to induce favorable charge rearrangement. The self-created electron-rich Co 3 O 4 and electron-deficient Ru sites at heterointerfaces are indispensable for the activation of the B-H bond in NH 3 BH 3 and the O H bond in H 2 O, respectively. The synergistic electronic interaction between the electron-rich Co 3 O 4 and electron-deficient Ru sites at the heterointerfaces resulted in an optimal Ru-Co 3 O 4 heterostructure that exhibited outstanding catalytic activity for the hydrolysis of AB in the presence of NaOH. The heterostructure had an extremely high hydrogen generation rate (HGR) of 12238 mL min −1 g cat -1 and an expected high turnover frequency (TOF) of 755 mol H2 mol Ru -1 min −1 at 298 K. The activation energy needed for the hydrolysis was low (36.65 kJ mol −1 ). This study opens up a new avenue for the rational design of high-performance catalysts for AB dehydrogenation based on the Mott-Schottky effect.
研究领域:
催化化学
·
能源材料
·
纳米材料科学
·
表面科学
·
氢能源技术
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）