SEPARATION AND PURIFICATION TECHNOLOGY
·
2022
·
IF 9.136
Renjie Li,Anli Chen,Qunfen Deng,Yujia Zhong,Ling Kong,Rui Yang
In this work, using melamine and MXene powder as precursors, NH 4 Cl as a template, a novel S-scheme heterojunction composite material g-C 3 N 4 /C-TiO 2 was synthesized by a one-step calcination method. During the calcination process, the gas template NH 4 Cl played a dual role, which not only striped the massive g-C 3 N 4 into porous flakes with a larger specific surface area but also striped the agglomerated MXene derivatives (C-TiO 2 ) nanoparticles, making them bind more closely with g-C 3 N 4 . The charge separation efficiency and photocatalytic performance were greatly improved due to the formation of heterojunction and the larger specific surface area of the sample. Within 50 min, the g-C 3 N 4 /C-TiO 2 exhibited high photocatalytic performance toward ciprofloxacin hydrochloride (CIP·HCl) with degradation efficiencies of 88.14% under visible light (λ ≥ 420 nm), which was 8.9 times higher than that of pure g-C 3 N 4 . In addition, we also used a series of characterizations to confirm the mechanism of S-scheme heterojunction and inferred the possible CIP photodegradation pathway.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
Scientific Reports
·
2017
·Vol. 7
·期 1
·1-11
·
IF 4.259
Shen Liyan,Xing Zipeng,Zou Jinlong,Li Zhenzi,Wu Xiaoyan,Zhang Yuchi,Zhu Qi,Yang Shilin,Zhou Wei
Black TiO 2 nanobelts/g-C 3 N 4 nanosheets laminated heterojunctions (b-TiO 2 /g-C 3 N 4 ) as visible-light-driven photocatalysts are fabricated through a simple hydrothermal-calcination process and an in - situ solid-state chemical reduction approach, followed by the mild thermal treatment (350 °C) in argon atmosphere. The prepared samples are evidently investigated by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, N 2 adsorption, and UV-visible diffuse reflectance spectroscopy, respectively. The results show that special laminated heterojunctions are formed between black TiO 2 nanobelts and g-C 3 N 4 nanosheets, which favor the separation of photogenerated electron-hole pairs. Furthermore, the presence of Ti 3+ and g-C 3 N 4 greatly enhance the absorption of visible light. The resultant b-TiO 2 /g-C 3 N 4 materials exhibit higher photocatalytic activity than that of g-C 3 N 4 , TiO 2 , b-TiO 2 and TiO 2 /g-C 3 N 4 for degradation of methyl orange (95%) and hydrogen evolution (555.8 μmol h −1 g −1 ) under visible light irradiation. The apparent reaction rate constant (k) of b-TiO 2 /g-C 3 N 4 is ~9 times higher than that of pristine TiO 2 . Therefore, the high-efficient laminated heterojunction composites will have potential applications in fields of environment and energy.
研究领域:
材料科学
·
光催化
·
纳米材料
·
环境功能材料
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能源材料
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半导体物理
·
表面化学
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2017
·
IF 3.582
Yu-pei Li,Fa-tang Li,Xiao-jing Wang,Jun Zhao,Jiang-nan Wei,Ying-juan Hao,Ying Liu
A quantum-sized hematite iron oxide (α-Fe 2 O 3 )/graphitic carbon nitride (g-C 3 N 4 ) hybrids have been designed and constructed through a facile in situ calcination treatment. The α-Fe 2 O 3 /g-C 3 N 4 hybrids were analyzed via various characterization techniques including XRD , TEM , UV–Vis DRS , XPS , and their photocatalytic efficiencies were evaluated by visible light-driven hydrogen evolution . The results reveal that the cooperation of α-Fe 2 O 3 and g-C 3 N 4 during fabrication process leads to synergy effects of not only the morphology but also the microstructure. These hybrids exhibit much higher hydrogen evolution efficiency than pure g-C 3 N 4 under visible-light illumination due to their improved light harvesting capability, enhancement of surface areas , predominant (110) facet exposure of α-Fe 2 O 3 as well as a prominent quantum size effect , and highly efficient electron transfer and separation. A proposed Z-scheme mechanism was further verified experimentally.
研究领域:
材料科学
·
光催化
·
纳米材料
·
能源化学
·
半导体物理
·
表面科学
✓ 已验证
DOI
高影响因子
JOURNAL OF CATALYSIS
·
2024
·
IF 6.5
Mingyuan Guo,Yongning Ma,Zhanqing Liu,Donghua Wang,Yuhao Yang,Xiaolong Li,Enzhou Liu
Halogen doping is an effective approach to regulate the electronic structure and improve photocatalytic properties of g-C 3 N 4 . Here, a salt-assisted approach was employed to prepare layered porous halogen-doped g-C 3 N 4 . The effects of halogen electronegativity and pore morphology were discussed. Highly electronegative F-doped g-C 3 N 4 with smaller pore size and higher surface area displayed the enhanced absorption property on reactants. The H 2 production rate decreased and the RhB degradation significantly increased with increasing the electronegativity of layered porous g-C 3 N 4 , which was significantly different from the conventional halogen-doped g-C 3 N 4 prepared with halogenated acid and monolayer g-C 3 N 4 . The decreased H 2 evolution can be ascribed to the strong adsorption property, and the strong interactions between halide ions and H + were difficult to be disassociated. Additionally, the RhB degradation performance of halogen-doped g-C 3 N 4 significantly increased with increasing the electronegativity. The most active species that dominated the RhB degradation of F-doped g-C 3 N 4 are leaved holes (h + ), which are totally different from that of the pristine g-C 3 N 4 and Cl/Br-doped g-C 3 N 4 (superoxide radicals,·O 2 – ). This work helps us to well understand the role and importance of electronegativity and pore morphology on the H 2 generation and RhB degradation properties of layered porous g-C 3 N 4 .
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Lijun Chen,Chenguang Wang,Guozhao Liu,Guanwen Su,Leping Dang,Hongyuan Wei
Rational utilization of the surface charge property of components is an effective method to prepare heterojunction. The surface of g-C 3 N 4 nanosheets (CNs) and black phosphorous nanosheets (BPs) both exhibit negative charge, which would produce repulsive force to hinder them from approaching each other. Herein, non-noble and low-toxic Cu(II) was selected to harmonize the CNs and BPs together under the interaction of surface charges, and the Cu(II) was reduced in situ to Cu with good conductivity, obtaining the sandwich-like product BPs/Cu/CNs with tight interface and high separation efficiency of photogenerated carriers. The composites exhibited attractive degradation performance for various pollutants under visible light, especially, 95.3 % of ciprofloxacin (10 mg/L, 200 mL) was removed in 60 min with 50 mg of 6BPs/4Cu/CNs as photocatalyst, and the removal ratio can still reach 87.4 % after the fifth reuse with negligible leaching of Cu ions. An unconventional type-II band structure was built in the BPs/Cu/CNs under the drive of internal electric field and mutual attraction of opposite charges, in which the e - from CB of BPs transferred to Cu and then combined with the h + from VB of CNs, leaving the e - from CB of CNs and h + from VB of BPs still work. Despite the same result to that of typical type-II band structure of BPs/CNs, the flow of photogenerated carriers in the BPs/Cu/CNs was more favorable in thermodynamics.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
Environmental Science-Nano
·
2019
·Vol. 6
·期 9
·2850-2862
·
IF 7.704
Xiaoyu Bai,Yi Li,Liangbo Xie,Xiaohui Liu,Sihui Zhan,Wenping Hu
Antibiotics accumulate because of their extensive use and difficult degradation, which can lead to the formation of novel antibiotic resistant genes and bacteria, which can cause damage to human health and the ecological environment. Here, we designed a novel photo-electro-Fenton-like (PEF-like) system with bifunctional Z-scheme WO3/g-C3N4 for accelerated decomposition and enhanced mineralization of stubborn ciprofloxacin (CIP). This PEF-like system, accompanied by visible light activation, with the optimal WO3/g-C3N4 (1 : 6) composite exhibited outstanding removal efficiency of CIP compared with a single photocatalysis system and electro-Fenton-like (EF-like) system, and the elimination rate reached 100% within 2 h under visible light irradiation. The WO3/g-C3N4 (1 : 6) composite displayed the strongest visible light absorption, the weakest recombination of electron–hole pairs, the highest photocurrent response and the lowest electrochemical impedance compared with pristine WO3 and g-C3N4. Significantly, WO3/g-C3N4 (1 : 6) played a dual role in the PEF-like system which could not only produce ˙OH, ˙O2− and h+ during photocatalysis, but could also generate ˙OH through the reactions of W5+ and photoexcited electrons of g-C3N4 for the decomposition of H2O2. It was worth noting that this bifunctional PEF-like catalyst with photoelectric synergy could replace Fe2+ in a conventional electro-Fenton reaction and the pH range was broadened while still maintaining efficient degradation efficiency in the range of 2–9. The PEF-like system maintained a high elimination rate of CIP after five consecutive runs which revealed that it possessed prominent stability and feasibility.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
·
2020
·
IF 3.085
Tianxu Zhang,Fei Chang,Yingfei Qi,Xinyi Zhang,Jieya Yang,Xiaoqi Liu,Shijie Li
In this investigation, a facile alkali-free one-pot synthetic protocol was developed to construct binary SnO 2 / g -C 3 N 4 composites for sake of environment friendliness. These composites were systematically characterized by various analytical techniques. X-ray powder diffraction (XRD) patterns, Fourier-transform infrared spectra (FT-IR), and X-ray photoelectron spectra (XPS) identified the coexistence of both components that were closely combined to generate heterojunction structures proven by high resolution transmission electron microscope (HRTEM) observations. These binary composites showed enhanced photocatalytic performance over methyl orange decolorization under visible light irradiation in comparison to bare g -C 3 N 4 , mostly attributing to morphological harmony of both ingredients, formation of heterojunction domains, and well-aligned band structures. Besides, the satisfactory reusability and structural stability of composites were identified. Basing on entrapping experiments and electron spin resonance (ESR) analyses, a possible photocatalysis mechanism was preliminarily inspected. It was noted that the variation of real weight percent of SnO 2 in composites was constrained to some degree, which should be settled in future work by appropriate modifications of such synthetic protocol.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
Frontiers in Energy
·
2020
·Vol. 14
·期 4
·759-766
·
IF 2.657
Bian Zhengxu,Tang Zehua,Xie Jinfeng,Zhang Junhao,Guo Xingmei,Liu Yuanjun,Yuan Aihua,Zhang Feng,Kong Qinghong
As the anode material of lithium-ion battery, silicon-based materials have a high theoretical capacity, but their volume changes greatly in the charging and discharging process. To ameliorate the volume expansion issue of silicon-based anode materials, g-C 3 N 4 /Si nanocomposites are prepared by using the magnesium thermal reduction technique. It is well known that g-C 3 N 4 /Si nanocomposites can not only improve the electronic transmission ability, but also ameliorate the physical properties of the material for adapting the stress and strain caused by the volume expansion of silicon in the lithiation and delithiation process. When g-C 3 N 4 /Si electrode is evaluated, the initial discharge capacity of g-C 3 N 4 /Si nanocomposites is as high as 1033.3 mAh/g at 0.1 A/g, and its reversible capacity is maintained at 548 mAh/g after 400 cycles. Meanwhile, the improved rate capability is achieved with a relatively high reversible specific capacity of 218 mAh/g at 2.0 A/g. The superior lithium storage performances benefit from the unique g-C 3 N 4 /Si nanostructure, which improves electroconductivity, reduces volume expansion, and accelerates lithium-ion transmission compared to pure silicon.
研究领域:
材料科学
·
能源存储
✓ 已验证
DOI
高影响因子
DALTON TRANSACTIONS
·
2019
·Vol. 48
·期 10
·3486-3495
·
IF 4.052
Juying Lei,Bin Chen,Weijia Lv,Liang Zhou,Lingzhi Wang,Yongdi Liu,Jinlong Zhang
A TiO2/g-C3N4 composite photocatalyst with an inverse opal structure and heterojunction has been successfully prepared by a relatively facile approach. The catalyst was characterized by a combination of XRD, SEM, HRTEM, XPS, PL, EIS and DRS techniques and applied for the photocatalytic degradation of organic pollutants represented by Rhodamine B, phenol and levofloxacin. The results of RhB degradation showed that the rate constant of inverse opal TiO2/g-C3N4 with the best compound ratio is 0.184 min−1, which is 2.7 times faster than that of normal TiO2/g-C3N4 and 4.2 times faster than that of inverse opal TiO2. The enhancement of photocatalytic activity may be attributed to the matched overlapping band structure and the interaction between inverse opal g-C3N4 and TiO2. The inverse opal structure of g-C3N4 has improved the optical absorption properties of g-C3N4 and the interaction between inverse opal g-C3N4 and TiO2 creates more interfaces for the efficient transfer of photogenerated electron–hole pairs to restrict the recombination, which was proved from the photoluminescence spectra (PL). Moreover, a possible photocatalytic mechanism has been tentatively proposed according to the experimental results. All in all, both the inverse opal structure and heterojunction construction play significant roles in the excellent photocatalytic degradation performance according to the mechanism investigation.
研究领域:
材料科学
·
环境科学
·
光催化
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Fei Guo,Dongsheng Li,Rui Ding,Jiaming Gao,Xuehua Ruan,Xiaobin Jiang,Gaohong He,Wu Xiao
Two-dimensional nanomaterials have the characteristics of high aspect ratio and high space utilization, which has huge potential advantages in gas separation. In this work, g-C 3 N 4 two-dimensional nanosheets with sieving pore structure were selected as templates and combined with ZIF-90 to construct a 0-dimensional/2-dimensional composite material ZIF-90@C 3 N 4 (ZCN). The complete two-dimensional g-C 3 N 4 nanosheets were stripped under acid etching conditions at 25 °C. ZIF-90 was distributed in an orderly manner on the two-dimensional nanosheets, and the nanosheets were spread out due to the growth of ZIF-90 to provide more free volume. The gas permeation experiment proved that the ZCN has a better CO 2 /N 2 separation performance. The ZCN/Pebax mixed matrix membrane (MMM) with the optimized 8.0 wt% ZCN loading showed an improved CO 2 permeability of 110.5 Barrer and a CO 2 /N 2 selectivity of 84.4, surpassing the Robeson upper bound (2008). The results demonstrated that the designed composite filler with 2D nanosheets is an effective strategy to enhance gas separation performance of MMMs and verified the application potential in gas purification industry.
研究领域:
材料科学
·
化学工程
·
气体分离技术
✓ 已验证
DOI
高影响因子
Frontiers in Energy
·
2023
·Vol. 18
·期 1
·110-121
·
IF 2.9
Ge Yang,Shen Quanhao,Zhang Qi,Li Naixu,Lu Danchen,Zhang Zhaoming,Fu Zhiwei,Zhou Jiancheng
Metal-free graphitic carbon nitride (g-C 3 N 4 ) has captured significant attention as a low-cost and efficient hydrogen production photocatalyst through. Effectively regulating the microstructure and accelerating the separation of photogenerated carriers remain crucial strategies for promoting the photocatalytic performance of this material. Herein, a novel sulfur–carbon co-doped g-C 3 N 4 (SCCN) hierarchical microtubules filled with abundant nanosheets inside by thermal polymerization is reported. Numerous nanosheets create abundant pores and cavities inside the SCCN microtubes, thereby increasing the specific surface area of g-C 3 N 4 and providing sufficient reactant attachment sites. Besides, the hierarchical structure of SCCN microtubules strengthens the reflection and scattering of light, and the utilization of visible light is favorably affected. More importantly, co-doping S and C has greatly improved the photocatalytic performance of graphitic carbon nitride, optimized the band gap structure and enhanced the photogenerated carrier splitting. Consequently, the SCCN exhibits a remarkable photocatalytic H 2 evolution rate of 4868 µmol/(g·h). This work demonstrates the potential of multi-nonmetal doped g-C 3 N 4 as the ideal photocatalyst for H 2 evolution.
研究领域:
材料科学
·
纳米技术
·
催化
·
能量转换
·
环境科学
✓ 已验证
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2022
·Vol. 46
·期 42
·20146-20153
·
IF 3.925
Zhengxing Gong,Jing Luo,Xinrong Shao,Xu Sun,Huan Wang,Dan Wu,Dawei Fan,Yuyang Li,Qin Wei,Huangxian Ju
A novel quenching electrochemiluminescence (ECL) immunosensor for the trace detection of neuron-specific enolase (NSE) was developed. Doping CdS with Zn2+ to obtain ZnCdS not only significantly improves the original properties of CdS, but also can be loaded onto the surface of g-C3N4 to form a special complex structure, which effectively improves the ECL performance of g-C3N4. Rh0.6Ru0.4 alloys with flower-like structures were prepared by simple hydrothermal synthesis, with excellent electrical conductivity and catalytic performance. Due to its special flower-like structure with a large specific surface area, Ag nanoparticles can be uniformly loaded on its surface to form Rh0.6Ru0.4@Ag composites. Through spectral comparison, it was found that Rh0.6Ru0.4@Ag has strong UV-vis absorption in the ECL emission wavelength range of g-C3N4, which can generate resonance energy transfer, thereby effectively quenching the ECL signal. The immunosensor has a wide detection range with a detection limit of 16 fg mL−1 (S/N = 3), good stability and biocompatibility, and has great potential in clinical application.
研究领域:
分析化学
·
生物传感器
·
生物医学工程
·
材料科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）