MOLECULES
·
2022
·Vol. 27
·期 21
·7178
·
IF 4.927
Yan Chen,Ao Li,Xiuli Fu,Zhijian Peng
The difficulty of exposing active sites and easy recombination of photogenerated carriers have always been two critical problems restricting the photocatalytic activity of g-C3N4. Herein, a simple (NH4)2MoO4-induced one-step calcination method was successfully introduced to transform bulk g-C3N4into g-C3N4/MoO2composites with a large specific surface area. During the calcination, with the assistance of NH3and water vapor produced by ammonium molybdate, the pyrolytical oxidation and depolymerization of a g-C3N4interlayer were accelerated, finally realizing the exfoliation of the g-C3N4. Furthermore, another pyrolytical product of ammonium molybdate was transformed into MoO2under an NH3atmosphere, which was in situ loaded on the surface of a g-C3N4nanosheet. Additionally, the results of photocatalytic hydrogen evolution under visible light show that the optimal g-C3N4/MoO2composite has a high specific surface area and much improved performance, which is 4.1 times that of pure bulk g-C3N4. Such performance improvement can be attributed to the full exposure of active sites and the formation of abundant heterojunctions. However, with an increasing feed amount of ammonium molybdate, the oxidation degree of g-C3N4was enhanced, which would widen the band gap of g-C3N4, leading to a weaker response ability to visible light. The present strategy will provide a new idea for the simple realization of exfoliation and constructing a heterojunction for g-C3N4simultaneously.Keywords:g-C3N4;MoO2;exfoliation;photocatalytic hydrogen evolution
研究领域:
材料科学
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化学
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2024
·
IF 8.1
Ligang Ma,Le Xu,Yihuan Ding,Chao Lin,Yuqing Yang,Xiaoqian Ai
Reasonable design and preparation of effective interface engineering to accelerate charge transfer is the key to achieve the improvement of heterojunction photocatalysts. In this study, a Ti 3 C 2 -MoS 2 -ZnIn 2 S 4 (TMZ) heterojunction was designed and successfully synthesized by sequentially growing MoS 2 and ZnIn 2 S 4 layered structures on highly conductive Ti 3 C 2 using a two-step hydrothermal method. This configuration effectively separated photogenerated carrier, thereby improving the efficiency of photocatalytic hydrogen production. The effects of the amount of Ti 3 C 2 -MoS 2 on the microstructure, morphology, optical properties and photocatalytic H 2 production of TMZ heterojunctions were investigated. Results demonstrated that Ti 3 C 2 , MoS 2 , and ZnIn 2 S 4 intricately interpenetrated to form a tightly bound TMZ heterojunction with a well-defined heterojunctions interface. This interface is beneficial for the separation of photogenerated carriers, thereby boosting the photocatalytic performance. The dynamic process of carrier separation was investigated in detail using photocurrent measurements, EIS Nyquist plots, photoluminescence, and fluorescence lifetime analysis. Additionally, compared to pristine ZnIn 2 S 4 , the absorption edge of TMZ sample exhibited a redshift, indicating an expanded absorption range in the visible spectrum. Finally, the mechanism by which TMZ enhances the efficiency of photocatalytic H 2 production is thoroughly analyzed.
研究领域:
材料科学
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能源科学
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光催化
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2023
·
IF 22.1
Chao Wu,Weixin Huang,Huanmin Liu,Kangle Lv,Qin Li
Facing the increasingly serious issues of energy crisis and environmental pollution, it is vital to develop efficient and durable photocatalysis systems for hydrogen (H 2 ) production from water splitting. However, for the famous CdS-based systems, the bottleneck of poor efficiency and low stability arisen from photocorrosion has not been broken through yet. In this study, a ternary composite of CdS , MoS 2 and Ti 3 C 2 MXene with intimately contact interfaces was successfully constructed via an in situ growth method, which exhibited reinforced photocatalytic H 2 -production activity and increased photocorrosion resistant capability. Both of experimental characterizations and density functional theory (DFT) calculations well proved that the photogenerated holes and electrons of CdS timely migrated to Ti 3 C 2 and MoS 2 , respectively. As a consequence, the optimal sample displayed a high H 2 production rate of 14.88 mmol·h −1 ·g −1 with a lifetime of up to 78 h, and the component and structure of the composite were kept intact during the photocatalysis reaction. This work highlights the synergistic effect of the Ti 3 C 2 MXene and MoS 2 as redox dual cocatalysts on the promoted photocatalytic performance and durability of CdS, which can be anticipated to significantly enhance the commercial availability of CdS and even boost its incorporation into industrial applications.
研究领域:
材料科学
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能源科学
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2020
·
IF 7.489
Ting Song,Linquan Hou,Bei Long,Atif Ali,Guo-Jun Deng
The fabrication of ultrathin MXene (Ti 3 C 2 )-based photocatalysts is highly intriguing as the charges can vectorially transfer along the two-dimensional (2D) direction despite being challenging. Herein, ultrathin Ti 3 C 2 (TiC) nanosheets with excellent conductivity are rationally introduced to ultrathin metal-free 0D/2D black phosphorus (BQ)/ultrathin g-C 3 N 4 (UCN) heterojunction for improving photocatalytic H 2 production activity. The optimized BQ/TiC/UCN composite displayed obvious advantages such as the strong interfacial contact and enhanced visible-light capture. Importantly, the incorporation of TiC nanosheets substantially accelerates charge transfer to fast separation of photoinduced carriers between BQ and UCN . The optimized BQ/TiC/UCN composite exhibited 47.2 and 19.4 folds higher photocatalytic activity (18.42 mmol h −1 g −1 ) than that of bulk g-C 3 N 4 (BCN) and UCN, respectively. The microstructure, composition, and optical properties of BQ/TiC/UCN composite were carefully characterized. The current research results may furnish fresh insights into the exploration of MXene (Ti 3 C 2 )-based catalysts with high solar energy utilization.
研究领域:
材料科学
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能源化学
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产品关联
DOI
PubMed
高影响因子
MOLECULES
·
2024
·Vol. 29
·期 2
·493
·
IF 4.2
Ligang Ma,Chao Lin,Wenjun Jiang,Shun Yan,Huilin Jiang,Xiang Song,Xiaoqian Ai,Xiaoxiao Cao,Yihuan Ding
Selective supported catalysts have emerged as a promising approach to enhance carrier separation, particularly in the realm of photocatalytic hydrogen production. Herein, a pioneering exploration involves the loading of PdS and Pt catalyst onto g-C3N4nanosheets to construct g-C3N4@PdS@Pt nanocomposites. The photocatalytic activity of nanocomposites was evaluated under visible light and full spectrum irradiation. The results show that g-C3N4@PdS@Pt nanocomposites exhibit excellent properties. Under visible light irradiation, these nanocomposites exhibit a remarkable production rate of 1289 μmol·g−1·h−1, marking a staggering 60-fold increase compared to g-C3N4@Pt (20.9 μmol·g−1·h−1). Furthermore, when subjected to full spectrum irradiation, the hydrogen production efficiency of g-C3N4@PdS@Pt-3 nanocomposites reaches an impressive 11,438 μmol·g−1·h−1, representing an eightfold enhancement compared to g-C3N4@Pt (1452 μmol·g−1·h−1) under identical conditions. Detailed investigations into the microstructure and optical properties of g-C3N4@PdS catalysts were conducted, shedding light on the mechanisms governing photocatalytic hydrogen production. This study offers valuable insights into the potential of these nanocomposites and their pivotal role in advancing photocatalysis.
研究领域:
材料科学
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能源科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Mei Dong,Wenjun Li,Liang Geng,Ruixue Huang,Yuan Liu,Hongli Han
Herein, CuCo 2 O 4 hollow porous nanospheres (HPN), nanosheets (NS), and nanowires (NW) were synthesized via solvothermal and calcination processes, and were used to construct efficient heterojunctions with Cd 0.5 Zn 0.5 S. Interestingly, the unique hollow porous structure exhibits enhanced light absorption, large pore diameter (12.57 nm), and strong hydrophilicity (10.05°). Photocatalytic results indicate that CuCo 2 O 4 HPN/Cd 0.5 Zn 0.5 S achieves the optimal hydrogen production rate, which is 5.4, 1.2, and 1.3 times than that of pure Cd 0.5 Zn 0.5 S, CuCo 2 O 4 NW/Cd 0.5 Zn 0.5 S and CuCo 2 O 4 NS/Cd 0.5 Zn 0.5 S, respectively. High-resolution TEM and theoretical calculations confirm that (311)/(111) facet junctions in CuCo 2 O 4 nanospheres form a work function difference (0.24 eV), which significantly facilitates charge transfer and separation. Mott-Schottky and Ultraviolet photoelectron spectroscopy analyses indicate that p-type CuCo 2 O 4 and n-type Cd 0.5 Zn 0.5 S have staggered energy levels and a distinct Fermi level difference (1.85 eV), which leads to rearrangement of the Fermi energy level and modulation of charge transfer pathway. The resulting energy band bending and built-in electric field promote charge transfer at the heterojunction interface more effectively. The synergistic mechanism of the facet junction and p-n junction finally achieves high-efficiency hydrogen production. This work provides new insights into how to construct efficient p-n heterojunction photocatalysts and presents the synergistic mechanism of facet junction and p-n junction.
研究领域:
材料科学
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能源科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
PHOTOCHEMICAL & PHOTOBIOLOGICAL SCIENCES
·
2019
·Vol. 19
·期 1
·80-87
·
IF 2.408
Tingting Wei,Zhanbin Jin,Fengyan Li,Dandan Yan,Lin Xu
In this work, a series of samples of Cd0.5Zn0.5S (ZCS) nanoparticles decorated with porous TaON were successfully prepared as a direct Z-scheme system. The photocatalytic evolution of H2 with a high efficiency was explored using NiS decorated with TaON sensitized ZCS nanocomposites (NiS-TaON/ZCS) and Na2SO3/Na2S as sacrificial reagents. The results showed that 0.5 wt% NiS deposited on the surface of 4 wt% TaON-ZCS nanocomposites could reach the highest photocatalytic H2 evolution rate of 34.8 mmol h−1 g−1 with a maximum quantum yield of about 25.5% under 420 nm monochromatic light. The activity of the TaON-ZCS photocatalyst for photocatalytic H2 evolution is higher than that of either pure ZCS or TaON. This high photocatalytic performance is ascribed firstly to the hierarchical structure of the coupled semiconductor system and secondly to the efficient transfer and separation of photogenerated charge carriers with NiS as a cocatalyst, which could serve as an electron collector.
研究领域:
材料科学
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能源科学
·
化学工程
✓ 已验证
DOI
高影响因子
Small
·
2024
·
IF 13
Qiaona Liu,Xin Han,An Qian,Jiayu Qian,Xin Pu,Lei Ye,Jinshan Zhan,Jian Zhang,Qiang Yang,Jichang Liu
Building heterojunctions and exposing more catalytic active sites are effective strategies to enhance the photocatalytic hydrogen evolution activity. Herein, TiO 2 nanosheets are oxidized in situ on Ru-loaded MXene as carriers and subsequently loaded with uniform 2D CdS via hydrothermal method to obtain 2D Ru/Ti 3 C 2 -TiO 2 /CdS composite photocatalysts that integrate heterojunctions and cocatalysts. The formation of heterojunction between CdS and TiO 2 is conducive to promoting the separation and transfer of photogenerated charges, simultaneously, Ru/Ti 3 C 2 with the fully exposed Ru and Ti 3 C 2 can act as effective active sites of photocatalytic hydrogen production reaction. The composite photocatalyst exhibits an improved hydrogen production rate with 5479 µmol g −1 h −1 , which is 5, 3, and four times more than that of pristine CdS, CdS loaded Ti 3 C 2 -TiO 2 and CdS loaded Ru-TiO 2 respectively. The results reveal that the notable enhancement in performance can primarily be ascribed to the introduction of the TiO 2 /CdS heterojunction and the efficient cocatalysts of Ru/Ti 3 C 2 . Moreover, the 2D Ti 3 C 2 with high conductivity as carriers can increase charge transfer, and its 2D structure can serve as a template for growing 2D photocatalysts with higher activity. The interface engineering with multiple interfaces can offer novel insights for the advancement of efficient hydrogen evolution reaction catalysts.
研究领域:
材料科学
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能源化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Materiomics
·
2015
·
IF 0
Junwei Fu,Shaowen Cao,Jiaguo Yu
Photocatalytic hydrogen generation is one of the most promising solutions to convert solar power into green chemical energy. In this work, a multi-component TiO 2 –Ag–Cu 2 O composite was obtained through simple impregnation-calcination of Cu 2 O and subsequent photodeposition of Ag onto electrospun TiO 2 nanotubes. The resulting TiO 2 –Ag–Cu 2 O photocatalyst exhibits excellent photocatalytic H 2 evolution activity due to the synergetic effect of Ag and Cu 2 O on electrospun TiO 2 nanotubes. A dual Z-scheme charge transfer pathway for photocatalytic reactions over TiO 2 –Ag–Cu 2 O composite was proposed and discussed. This work provides a prototype for designing Z-scheme photocatalyst with Ag as an electron mediator.
研究领域:
材料科学
·
能源科学
✓ 已验证
DOI
RSC Advances
·
2025
·Vol. 15
·期 22
·17665-17674
·
IF 4.6
Hao Ji,Zelin Li,Zhenyi Xu,Lingmin Yao,Rui Tong,Shan Zhang
Developing an efficient visible-light-responsive catalyst for the hydrogen evolution reaction (HER) is essential for addressing energy scarcity and environmental pollution. In this study, one-dimensional Co3O4 (CO) nanoparticles were synthesized via electrospinning and subsequently sulfurized using a low-temperature solvothermal method. These sulfurized one-dimensional CO nanoparticles were then combined with two-dimensional sheet-like ZnIn2S4 (ZIS) to form a p–n heterojunction composite semiconductor photocatalyst (SCO/ZIS). The one-dimensional CO nanoparticles obtained through electrospinning significantly enhance the catalytic activity and efficiency, while sulfurization further improves their electronic structure and surface properties. The built-in electric field at the p–n heterojunction interface between n-type ZIS and p-type SCO effectively inhibits the recombination of photogenerated electron–hole pairs while facilitating electron transfer. Additionally, the incorporation of one-dimensional SCO into sheet-like ZIS prevents ZIS stacking, improving sunlight utilization and substantially enhancing photocatalytic HER performance. Our results demonstrate that SCO/ZIS achieves a superior HER rate of 4300.3 μmol g−1 h−1 under visible light, which is 7.45 times higher than that of pristine ZIS, while also exhibiting excellent photocatalytic stability.
研究领域:
材料科学
·
能源化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ChemCatChem
·
2018
·Vol. 11
·期 3
·1069-1075
·
IF 4.674
Rui Tong,Zhi Sun,Xiongwei Zhong,Xina Wang,Jincheng Xu,Ye Yang,Baomin Xu,Shuangpeng Wang,Hui Pan
Graphical Photocatalytic hydrogen production : g-C 3 N 4 /CeCO 3 OH/CeO 2 ternary composite showed greatly enhanced photocatalytic performance for hydrogen production under visible light irradiation. Promoting the separation of photo-generated carriers is significantly important to improve the efficiency of photocatalytic hydrogen production. Therefore, we prepared g-C 3 N 4 /CeCO 3 OH/CeO 2 (CeCeCN) ternary nanocomposite via an easy synthetic way using g-C 3 N 4 and CeO 2 as reactants. A CeCO 3 OH layer was formed and resulted in the novel ternary photocatalyst. The CeCeCN composite shows superior photocatalytic (PC) H 2 generation performance in sunlight excitation. The H 2 evolution rate is about 764 μmol h −1 g −1 , which is over 11 times larger than those of g-C 3 N 4 and CeO 2 . Compared with g-C 3 N 4 and CeO 2 , CeCeCN further shows a larger photo-response current density and a lower charge-transfer resistance. The remarkably increased photocatalytic property of CeCeCN is because of the efficient charge migration induced by the formed heterojunction. Our findings demonstrate that building multi-heterostructures can liberate more excited electrons for efficient hydrogen production under sunlight.
研究领域:
材料科学
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能源科学
✓ 已验证
DOI
高影响因子
NANO
·
2022
·
IF 1.438
Kaiyue Liang,Mingcai Yin,Yixian Li,Yaoting Fan,Zhongjun Li
CdS and MoS 2 are both promising photocatalytic materials for hydrogen production and lots of MoS 2 /CdS composites have been investigated. However, most of the previous work focused on relatively stable hexagonal CdS; researches on cubic CdS are still rare mainly due to its unstability. Then in this paper, a ternary composite MoS 2 /CN/CdS composed of cubic CdS, MoS 2 and graphitic carbon nitride (g-C 3 N 4 , abbreviated as CN) was prepared by simple in situ precipitation of cubic CdS on MoS 2 /CN at room temperature. Based on a series of characterizations, the photocatalytic hydrogen production performance of MoS 2 /CN/CdS was studied. The results showed that when the amount of MoS 2 /CN was 10 wt.%, the activity reached 1253.2 μ mol h − 1 , about 110 times that of pure CdS. Especially, its stability was investigated in detail by cyclic hydrogen production tests, which indicated that although the activity decreased after the first cycle, it was stable in the following three cycles mainly due to the existence of CN. Namely, a relatively stable and high performance cubic CdS-based ternary composite was achieved. This research can provide some new insights into the design of cubic CdS-based photocatalysts.
研究领域:
材料科学
·
能源科学
✓ 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）