DALTON TRANSACTIONS
·
2023
·Vol. 52
·期 23
·7869-7875
·
IF 4
Deling Wang,Lu Chen,Yuzhou Xia,Ruowen Liang,Xiyao Liu,Shaoming Ying,Guiyang Yan
Developing novel photocatalysts with an intimate interface and sufficient contact is significant for the separation and migration of photogenerated carriers. In this work, a novel Co@NC/ZnIn2S4 heterojunction with a strong Co–S chemical bond was formed at the interface between Co@NC and ZnIn2S4, which accelerated charge separation. Meanwhile, the recombination of the electron–hole pairs was further restricted by the Co@NC/ZnIn2S4 Schottky junction. The Co@NC (5 wt%)/ZnIn2S4 composite exhibited an H2 evolution rate of 33.3 μmol h−1, which is 6.1 times higher than that of the pristine ZnIn2S4, and Co@NC/ZnIn2S4 showed excellent stability in the photocatalytic water splitting reaction. Its apparent quantum yield reached 38% at 420 nm. Furthermore, the Kelvin probe test results showed that the interfacial electric field formed as the driving force for interface charge transfer was oriented from Co@NC to ZnIn2S4. In addition, the Co–S bond as a high-speed channel facilitated the interfacial electron transfer. This work reveals that in situ formed chemical bonds will pave the way for designing high-efficiency heterojunction photocatalysts.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENERGY & FUELS
·
2023
·
IF 5.3
Chao Tang,Guolang Zhou,Jianmei Chen,Jingzhou Yin,Yuxin Li,Cheng Liu,Qiaoqi Li,Tianshi Wang,Ziqiang Wang,Shizheng Wen,Benlin Dai,Feihu Mu,Lili Zhang
Developing nonprecious metal catalysts with fast charge transfer ability, abundant active sites, and easy recovery is of great significance toward sodium borohydride (NaBH4) hydrolysis for hydrogen (H2) production in alkaline solutions. Herein, magnetically separated nitrogen-doped carbon-supported cobalt oxide (CoxOy@NC) nanoparticles were prepared successfully by converting pyrazine-based covalent organic frameworks (COFs). Due to the porous structure and nitrogen-rich characteristics of the precursor, the prepared catalyst CoxOy@NC exhibited good conductivity and charge transfer ability. Cobalt oxide nanoparticles and nitrogen-doped carbon matrix are bonded by the Co–N bond, which makes full use of the conductivity of the substrate and the high activity of the cobalt oxide catalyst. Therefore, CoxOy@NC exhibits an excellent synergistic effect between CoxOy and NC. The H2 generation rate reaches a maximum of 2082.13 mL/min/g from NaBH4 in alkaline solutions. In addition, CoxOy@NC also exhibits good magnetic separation capability, which greatly simplifies the catalyst separation process. Density functional theory (DFT) calculation results indicate that Co2+ is the dominant active component in the heterogeneous catalyst CoxOy@NC. This work broadens new horizons for the development of COFs derivative catalysts for hydrogen production from sodium borohydride hydrolysis.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2023
·
IF 9.9
Chao Liu,Wen Xiao,Guiyun Yu,Qiang Wang,Jiawei Hu,Chenghao Xu,Xinyi Du,Jianguang Xu,Qinfang Zhang,Zhigang Zou
Developing efficient heterojunction photocatalysts that have a high charge carrier separation rate and improved light-harvesting capacity is a crucial step in solving energy crisis and reducing environmental pollution. Herein, we synthesized few-layered Ti 3 C 2 MXene sheets (MXs) by a manual shaking process, and combined with CdIn 2 S 4 (CIS) to construct novel Ti 3 C 2 MXene/CdIn 2 S 4 (MXCIS) Schottky heterojunction through a solvothermal method. The strong interface between two-dimensional (2D) Ti 3 C 2 MXene and 2D CIS nanoplates led to enhanced light-harvesting capacity and promoted charge separation rate. Additionally, the presence of S vacancies on the MXCIS surface helped to trap free electrons. The optimal sample, 5-MXCIS (with 5 wt% MXs loading), exhibited outstanding performance for photocatalytic hydrogen (H 2 ) evolution and Cr(VI) reduction under visible light due to the synergistic effect of enhanced light-harvesting capacity and charge separation rate. The charge transfer kinetics was thoroughly studied using multiple techniques. The reactive species of • O 2 − , • OH and h + were generated in 5-MXCIS system, and e − and • O 2 − radicals were found to be the main contributors to Cr(VI) photoreduction. Based on the characterization results, a possible photocatalytic mechanism for H 2 evolution and Cr(VI) reduction was proposed. On the whole, this work provides new insights into the design of 2D/2D MXene-based Schottky heterojunction photocatalysts for boosting photocatalytic efficiency.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Materials Today Energy
·
2023
·
IF 9.3
Man Zhou,Suting Xue,Qin Feng,Xuan Liang,Wangchen Wu,Yanli Zhou,Minmin Ni,Xudong Zheng,Song Xu,Jin Zhao,Zhongyu Li
Noble metal nanoparticles (NMNPs) modified semiconductors play important roles in heterogeneous catalysis . However, for the ultra-small NMNPs (<5 nm) on TiO 2 , the problems of easy agglomeration and quick deactivation highlight the need for highly efficient protection of ultra-small NMNPs. Here, we introduce a novel structure of carbonized liquid crystals (CLCs) protected Pt NPs on TiO 2 , which involves in-situ photo-reduction of chloroplatinic acid to ultra-small Pt NPs in lamellar liquid crystals. According to the results of morphological structures, CLCs changed the contact type of Pt/TiO 2 from ‘face-contact’ to ‘point-contact’, which was consistent with our simulation results. Compared with the bare Pt/TiO 2 , the visible-light photocatalytic H 2 production rate of C–Pt/TiO 2 exhibited 1.75-fold enhancement under the protection of CLCs (26.73 mmol g −1 h −1 vs. 15.26 mmol g −1 h −1 ). Especially, the marriage of CLCs and the traditional Pt/TiO 2 photocatalyst achieved long-term stability, which remained 87% of the original rate at the sixth cycle.
✓ 已验证
产品关联
DOI
高影响因子
Science Bulletin
·
2023
·
IF 18.9
Guangxun Sun,Dongyuan Liu,Min Li,Shu Tao,Zekun Guan,Yanfei Chen,Shihuan Liu,Qingzhou Du,Han Guo,Xinyue Yuan,Xinying Zhang,Houyu Zhu,Bin Liu,Yuan Pan
Development of efficient catalysts with high atomic utilization and turnover frequency (TOF) for H 2 activation in slurry phase hydrocracking (SPHC) is crucial for the conversion of vacuum residue (VR). Herein, for the first time, we reported a robust and stable single atoms (SAs) Mo catalyst through a polymerization-pyrolysis- in situ sulfurization strategy for activating H 2 in SPHC of VR. An interesting atomic coordination structural dynamic evolution of Mo active sites was discovered. During hydrocracking of VR, the O atoms that coordinated with Mo were gradually replaced by S atoms, which led to the O/S exchange process. The coordination structure of the Mo SAs changed from pre-reaction Mo-O 3 S 1 to post-reaction Mo-O 1 S 3 coordination configurations, promoting the efficient homolytic cleavage activation of H 2 into H radical species effectively. The evolved Mo SAs catalyst exhibited robust catalytic hydrogenation activity with the per pass conversion of VR of 65 wt%, product yield of liquid oils of 93 wt%, coke content of only 0.63 wt%, TOF calculated for total metals up to 0.35 s −1 , and good cyclic stability. Theoretical calculation reveals that the significant variation of occupied Mo 4d states before and after H 2 interaction has a direct bearing on the dynamic evolution of Mo SAs catalyst structure. The lower d -band center of Mo-O 1 S 3 site indicates that atomic H diffusion is easy, which is conducive to catalytic hydrogenation. The finding of this study is of great significance to the development of high atom economy catalysts for the industrial application of heavy oil upgrading technology .
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Inorganic Chemistry Frontiers
·
2019
·Vol. 6
·期 8
·2043-2049
·
IF 5.934
Di Liu,Guangsheng Pang,Zhiyong Tang,Shouhua Feng
Interfacial engineering has demonstrated a significant effect on fabricating highly efficient membranes for gas separation. Herein, we introduced a new way to prepare a soft MOF membrane with a modified interface using polyelectrolyte branched polyethyleneimine (PEI) as the joint material. Assembled with layered graphene oxide (GO) and zeolitic imidazolate framework-8 (ZIF-8) nanocrystals, branched PEI not only functions as a soft coat onto the ZIF-8 surface to overcome the rigid nature but also well connects with GO nanosheets via electrostatic attraction, thus preventing the fracture of the membrane. When employed as the gas separation membrane for H2/CH4, the long gas diffusion pathway determined by layered GO and the accurate sieving effect endowed by ZIF-8 enable the remarkable permeance and selectivity. Furthermore, by simply altering the content of GO nanosheets and ZIF-8 nanocrystals in the composite membrane, one can easily adjust the permeance and selectivity toward the separation of H2/CH4 gas mixture.
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2019
·
IF 8.456
Junfang Ding,Liping Li,Haorui Zheng,Ying Zuo,Xiyang Wang,Huixia Li,Shaoqing Chen,Dan Zhang,Xingliang Xu,Guangshe Li
Nanomaterials are widely used as redox-type reaction catalysts, while reactant adsorption and O2 activation are hardly to be promoted simultaneously, restricting their applications in many important catalytic fields such as preferential CO oxidation (CO-PROX) in H2-rich stream. In this work, an interface-enhanced Co3O4–CuCoO2 nanomesh was initially synthesized by a hydrothermal process using aluminum powder as a sacrificial agent. This nanomesh is systematically characterized by powder X-ray diffraction, scanning electron microscopy, transmission electron microscopy, N2 adsorption, X-ray photoelectron spectroscopy, UV–vis absorption spectroscopy, Raman spectroscopy, X-ray absorption near-edge spectroscopy, hydrogen temperature-programmed reduction, and oxygen temperature-programmed desorption. It is demonstrated that the nanomesh possesses high-density nanopores, enabling a large number of CO adsorption sites exposed to the surface. Meanwhile, electron transfer from O2– to Co3+/Co2+ and the weakened bonding strength of Co–O bond at surfaces promoted the oxygen activation and redox ability of Co3O4. When tested as a catalyst for CO-PROX, this nanomesh with an optimized pore structure and a surface electronic structure, exhibits a strikingly high catalytic oxidation activity at low temperatures as well as a broader operation temperature window (i.e., CO conversion >99.0%, 100–200 °C) in the CO selective oxidation reaction. The present finding should be highly useful in promoting the quest for better CO-PROX catalysts, a hot topic for proton exchange membrane fuel cells and automotive vehicles.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2018
·
IF 3.525
Qi-Feng Liu,Qian Zhang,Bing-Rui Liu,Shiyou Li,Jing-Jun Ma
Inefficient charge separation and limited light absorption are two critical issues associated with high-efficiency photocatalytic H 2 production using TiO 2 . Surface defects within a certain concentration range in photocatalyst materials are beneficial for photocatalytic activity. In this study, surface defects (oxygen vacancies and metal cation replacement defects) were induced with a facile and effective approach by surface doping with low-cost transition metals (Co, Ni, Cu, and Mn) on ultrafine TiO 2 . The obtained surface-defective TiO 2 exhibited a 3–4-fold improved activity compared to that of the original ultrafine TiO 2. In addition, a H 2 production rate of 3.4 μmol/h was obtained using visible light ( λ > 420 nm) irradiation. The apparent quantum yield (AQY) at 365 nm reached 36.9% over TiO 2 -Cu, significantly more than the commercial P25 TiO 2 . The enhancement of photocatalytic H 2 production activity can be attributed to improved rapid charge separation efficiency and expanded light absorption window. This hydrothermal treatment with transition metal was proven to be a very facile and effective method for obtaining surface defects.
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2018
·
IF 6.14
Yongjin Ma,Yuan Bian,Yi Liu,Anquan Zhu,Hong Wu,Hao Cui,Dewei Chu,Jun Pan
Photocatalytic hydrogen evolution from water splitting is a promising approach in energy conversion and storage. Here, the 0D/1D CdS quantum dots (QDs)/CeO2 nanorods heterojunction was designed and fabricated by a facile two-step method. The optimum photocatalytic H2 evolution activity for CeO2-based composites with 3 at. % CdS QDs (101.12 μ mol h–1 g–1) was 45 times as high as that of pure CeO2 nanorods (2.25 μ mol h–1 g–1) under light irradiation. Meanwhile, the photocurrent response intensity increased 17.75 times higher than pure CeO2 nanorods. Furthermore, the 0D/1D CdS QDs/CeO2 heterojunctions exhibited enhanced photocatalytic stability for long lifetime (60 h). The reasons that dramatically enhanced photocatalytic performance could be the improved light harvesting, enhanced photoresponse and stronger electronic conductivity while the CdS QDs was loaded in CeO2 nanorods to form the 0D/1D heterojunctions CdS QDs/CeO2 nanocomposites. What’s more, the remarkably increased photocatalytic performance of CdS QDs/CeO2 composites was mainly attributed to the Z-scheme between CdS QDs and CeO2 nanorods, which was confirmed by the PL (photoluminescence) method. Therefore, the proposed system is highly promising for large scale photocatalytic hydrogen evolution.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
·
2017
·
IF 6.844
Yanning Shi,Jingjing Chen,Zhiyong Mao,Bradley D. Fahlman,Dajian Wang
In this work, Z-scheme heterostructure were constructed over the visible light response g-C 3 N 4 photocatalysts by loading Porous silicon (PSi) to enhance the photocatalytic H 2 evolution performance. The synthesized Z-scheme g-C 3 N 4 /PSi composites with a PSi loading content of 2.50 wt% achieves the highest photocatalytic H 2 evolution rate at 870.4 µmol h −1 g −1 , which is about 2 times as high as the pure g-C 3 N 4 with H 2 evolution rate of 427.2 µmol h −1 g −1 . Various techniques including XRD, SEM, TEM, FTIR, XPS, UPS, PL and electrochemical method were employed to demonstrate the successful construction of g-C 3 N 4 /PSi composites and to investigate the origin of the enhanced potocatalytic activity. The formed heterostructure between g-C 3 N 4 nanosheets and PSi were verified to be the dominant reason for the enhancement of photocatalytic activity, resulting from the separation promotion of photogenerated charge carriers in a direct Z-scheme mechanism. This study presented a promising Z-scheme g-C 3 N 4 /PSi photocatalysts with promising H 2 evolution performance, which might drive the progress of solar energy conversion technologies.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2024
·
IF 9.4
Xin Liu,Shikai Wang,Jinghao Cao,Jiahui Yu,Jixian Dong,Yutong Zhao,Fuping Zhao,Dafeng Zhang,Xipeng Pu
Rational design of the morphology and heterojunction to accelerate the separation of electron-hole pairs has played an indispensable role in improving the photocatalytic hydrogen evolution . ZnIn 2 S 4 (ZIS) has aroused considerable attention in solar-to-chemical energy conversion due to its remarkable photoelectrical properties and relatively negative energy band, whereas it still suffers from the severe photogenerated carrier recombination and catalyst aggregation. Herein, guided by density functional theory calculations, the constructed FeSe 2 @ZnIn 2 S 4 (FS@ZIS) heterojunction model has a hydrogen Gibbs free energy closer to zero compared with pure ZIS and FS, which is beneficial for hydrogen adsorption and desorption on the photocatalyst surface. Therefore, a novel cross-like core–shell FS@ZIS Step-scheme (S-scheme) heterojunction was synthesized successfully by in-situ growing ZIS nanosheets on the surface of cross-like FS. The structure with cross-like core–shell morphology not only inhibits the agglomeration of ZIS to increase specific surface area , but also provides a tight interface with S-scheme heterojunction. Moreover, the S-scheme heterojunction with a tight interface can effectively separate electron-hole pairs, leaving photoinduced charges with higher potentials. Furthermore, FS@ZIS-20 possesses exceptional photothermal capabilities, enabling the conversion of optical energy from visible and near infrared light to heat, thereby further enhancing the photocatalysis reaction. As a result, the cross-like core–shell FS@ZIS S-scheme heterojunction exhibits an excellent photocatalytic hydrogen evolution rate (7.640 mmol g −1 h −1 ), which is 24 times higher than that of pure ZIS (0.319 mmol g −1 h −1 ) under visible and near infrared light. Furthermore, employing more in-depth density functional theory calculations further investigates the charge transfer pathway of the FS@ZIS S-scheme heterojunction. This work provides insights into the construction of S-scheme heterojunctions with core–shell structure and photothermal effect for photocatalytic evolution hydrogen.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF POWER SOURCES
·
2012
·
IF 4.951
Jing Yang,Ligang Feng,Fengzhan Si,Yuwei Zhang,Changpeng Liu,Wei Xing,Kunqi Wang
H 2 -mesoporphyrin IX and Zn-mesoporphyrin IX have been investigated as sensitizers for the titanium dioxide (TiO 2 ) film electrode to construct a new two-compartment photoelectrochemical biofuel cell (PEBFC). The PEBFC can convert the light and chemical energy to electricity by consuming photons and oxidizing glucose. The two sensitizers are similar with two carboxyl anchoring groups, except that the central hydrogen atoms in the H 2 -mesoporphyrin IX are replaced by zinc. To determine how cell performance is affected by the sensitizer, we analyze the photochemical and photoelectrochemical properties of the two sensitizers by physical characterization and photoelectrochemical experiments. The UV–Vis absorption spectra and X-ray photoelectron spectra (XPS) indicate that the interactions between the sensitizer and TiO 2 decrease in the order of H 2 -mesoporphyrin IX > Zn-mesoporphyrin IX. The interactions are also determined by Fourier transform infrared (FTIR) spectra which indicate that the two sensitizers are adsorbed on the TiO 2 film through the carboxyl groups. The photovoltaic characteristics show the Zn-mesoporphyrin IX is less effective in comparison with the H 2 -mesoporphyrin IX, since the Zn-mesoporphyrin IX enhances the back electron-transfer process, producing lower IPCE and current. These results reveal that the H 2 -mesoporphyrin IX is a more efficient sensitizer compared with the Zn-mesoporphyrin IX for the PEBFC.
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）