CHEMICAL ENGINEERING JOURNAL
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2022
·
IF 16.744
Xiangli Shi,Pengfei An,Qiong Zhang,Qi Song,Deli Jiang,Dan Tian,Di Li
Photocatalytic CO 2 conversion into value-added chemicals is a promising strategy to remedy the energy crisis and environmental pollution, yet developing cost-effective photocatalysts that can efficiently and selectively convert CO 2 to desirable products is still a great challenge. Herein, we construct a Fe 2 P nanoparticles decorated on the surface of the nitrogen vacancies (NVs) modified g-C 3 N 4 nanosheet hybrid photocatalyst (Fe 2 P/NVsCN) for photocatalytic conversion of CO 2 to CO. The NVs can significantly improve the visible light absorption due to the formation of midgap state, and the metallic Fe 2 P as the cocatalyst is beneficial to promote the photo-generated charge separation and migration, impede the side reaction, in which improve the activity and selectivity. By adjusting the contents of Fe 2 P and NVsCN, the optimal 20%-Fe 2 P/NVsCN(1:5) sample shows an excellent CO evolution rate in visible light of 22.48 µmol g -1 h −1 with 97.5% selectivity, which is superior to most reported g-C 3 N 4 -based photocatalysts. Furthermore, this photocatalyst also exhibits good stability due to the timely consumption of electrons, and it maintains stable CO evolution rate over 20 h. This work opens a new horizon for design and construction of active photocatalyst with high selectivity by synergistic modulating the surface vacancy and cocatalyst.
研究领域:
材料科学
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环境科学
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化学工程
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DOI
高影响因子
iScience
·
2024
·
IF 4.6
Ai-Ping Yan,Yu-Jue Qiu,Xing-En Wang,Guang-Hua Wang,Xian-Kui Wei,Xin-Tian Li,Xiao-Die Chen,Xing Shang,Shun-Liu Deng,Jian-Wei Zheng,Su-Yuan Xie
C 3 N 4 is widely applied in the synthesis of single-atom catalysts. However, understanding on the active site and the reaction mechanism is not fully in consensus. Especially, bare studies have considered the coordination environment of the single-atomic dopant and the effect of nitrogen vacancy on C 3 N 4 . In this study, we found that the presence of nitrogen vacancies promotes the activation of water and reduces the activation energy barrier for hydrogen generation. The results show that a synergistic effect between single-atom Pt and nitrogen vacancies enables the catalyst to achieve a superior hydrogen production rate of 3,890 μmol/g/h, which is 16.8 times higher than that of pristine C 3 N 4 . Moreover, the catalyst is also applicable for photocatalytic hydrogen production from seawater without significantly decreased hydrogen production rate. This study paves the way for the rational design and optimization of next-generation photocatalysts for sustainable energy applications, particularly in solar-driven hydrogen production.
研究领域:
材料科学
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能源化学
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DOI
PubMed
高影响因子
ACS ES&T Water
·
2024
·
IF 4.8
Yuxin Shi,Qiong Zhu,Lanlan Fu,Jixing Wang,Xinyan Lu,Ying Tao,Chi Zhang,Yongjie Wang,Kangning Xu,Huan Shang,Dieqing Zhang,Guisheng Li
The solar-powered photocatalytic oxygen reduction reaction is considered a promising alternative method for H2O2 production under mild reaction conditions. However, the intrinsic competitive pathway grossly inhibits the selectivity and final yield of H2O2 accompanying the loss of photogenerated electrons during the oxygen reduction reaction process. Herein, two-coordinate nitrogen (N2C) vacancy-rich g-C3N4 (DCN1.2) was developed by polymerization pyrolysis using the bottom-up strategy. DCN1.2 with a low-coordinated N2C-vacancy enabled an enhanced H2O2 production in a wide pH range. The optimized DCN1.2 demonstrated a H2O2 yield of 556.2 μmol·gcat–1·h–1 at pH = 10, which was approximately 3 times higher than that of pristine CN (202.7 μmol gcat–1·h–1). DFT calculations and photochemical experimental results revealed that N2C-vacancies induced the asymmetric electron distribution of DCN, thereby facilitating electron transfer and promoting the O2 adsorption/activation for H2O2 production. Additionally, EPR and situ FTIR measurements indicated that DCN1.2 could produce H2O2 via a sequential two-step single-electron pathway, thereby achieving efficient H2O2 production with good selectivity. This study provides guidance for the rational design of defect-engineering g-C3N4 catalysts for efficient photocatalytic H2O2 generation.
研究领域:
材料科学
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环境科学
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化学工程
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DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2020
·Vol. 44
·期 38
·16320-16328
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IF 3.288
Yuanyuan Yang,Wenting Guo,Yunpu Zhai,Qianwei Jin,Hao Zhao,Ruiqin Zhang,Yonggang Liu
Typical non-metallic semiconductor carbon nitride (CN) has enormous potential in the field of photocatalysis, but the easy recombination of the photo-generated charges severely limits its practical applications. Herein, oxygen-doped and nitrogen vacancy co-modified carbon nitride (ODCN) was prepared by simple reduction and oxidation treatments. The experimental results show that the modified CN can effectively enhance the photocatalytic activity, indicating that there is a synergy between oxygen doping and nitrogen vacancy. The photocatalytic hydrogen generation rate of ODCN is 364 μmol g−1 h−1, which is higher than that of bulk CN, nitrogen vacancy-modified carbon nitride (DCN) and oxygen-doped modified carbon nitride (OCN). As a consequence, our work provides a neoteric idea for the co-modification of carbon nitride by a variety of methods, which can significantly improve the photocatalytic activity of carbon nitride and is expected to be applied in practical applications.
研究领域:
材料科学
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能源科学
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产品关联
DOI
高影响因子
Reaction Kinetics Mechanisms and Catalysis
·
2018
·Vol. 125
·期 2
·1179-1190
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IF 1.515
Mao Yong,Wu Mingzai,Li Guang,Dai Peng,Yu Xinxin,Bai Zhiman,Chen Peng
For highly efficient photodegradation of organic pollutants, the enhancement of photocatalytic activity of metal-free photocatalyst graphitic carbon nitride (g-C 3 N 4 ) under visible light irradiation is meaningful, but still challenging due to the fast recombination of photogenerated electron–hole pairs, low quantum efficiency and specific surface area of pristine g-C 3 N 4 . To address these challenges, boron-doped g-C 3 N 4 together with nitrogen-vacancies (Bd-Nv-C 3 N 4 ) was designed and synthesized through a simple acid-assisted calcination of melamine without any further tedious operations. As expected, based on the synergistic effect of foreign elements doping (boron atoms doping) and intrinsic defects (nitrogen vacancies), the as-prepared novel Bd-Nv-C 3 N 4 photocatalyst shows lower band gap, higher surface area and separation efficiency of photogenerated electron–hole pairs, achieving a nearly tenfold increase of the phtocatalytic constant for methylene blue (MB) degradation compared to that of pristine g-C 3 N 4 without nitrogen-vacancies and boron-doping. This study provides a new train of thought and method for the design and preparation of nonmetal photocatalysts with enhanced visible light irradiation photocatalytic performance.
研究领域:
材料科学
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环境科学
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化学
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DOI
高影响因子
Journal of Water Process Engineering
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2024
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IF 6.3
Xu-Dong Miao,Rui-Xiang Zhang,Wen-Tao Li,Qian Wang,Yu-Han Cai,Yong Guo,Ai-Min Li
The increasing environmental risks associated with tetracycline (TC) have been of widespread interest in the development of adsorbents for the efficient treatment of TC. This work synthesized a high-performance boron carbonitride (BCN v O) with nitrogen-vacancies (N v ) and oxygen-doping (O d ) via a hydrogen peroxide mediated strategy. The adsorption capacity of BCN v O-1 for TC (202.85 mg/g) is 1.79 times higher than that of BCN (113.08 mg/g). The adsorption process is well described by the pseudo-second-order kinetic and controlled by surface and intra-pore diffusion. Langmuir can well characterize isothermal adsorption with the fitted maximum adsorption up to 440.53 mg/g. Thermodynamics indicates a spontaneous and endothermic progress in BCN v O-1 adsorption. The abundant pore structures promote pore filling of TC by BCN v O-1. N v and O d enhance BCN v O-1 proton capture, and the captured protons strengthen hydrogen bonding and electrostatic interactions during adsorption. The functional groups, aromatic regions, and B N rings on BCN v O-1 are involved in hydrogen bonding and π-π stacking to TC. BCN v O-1 has high adsorption performance, great environmental appropriateness and thermal regeneration performance, suggesting good prospects for its potential application in environmental wastewater treatment.
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
MATERIALS RESEARCH BULLETIN
·
2024
·
IF 5.3
Ruxue Ma,Han Zheng,Jing Wang,Xiucheng Zheng,Xiaoli Zhang,Xinxin Guan
Photocatalytic degradation is an effective and challenging strategy in purifying wastewaters containing organic pollutants. Thus, developing a suitable photocatalyst and clarifying the degradation mechanism are extremely worthwhile. In this work, Zn 2+ -decorated porous g-C 3 N 4 with nitrogen vacancies (g-C 3 N 4-δ ) is prepared with the facile sonication-calcination method. Benefitting from the modified geometric structure and electronic properties, compared with g-C 3 N 4-δ , the resulting composites deliver reduced micropore percentage, enhanced separation and migration of photogenerated carriers, narrowed band gap, and improved reducing capacity of photoinduced electrons, favoring the photocatalytic reaction. Particularly, Zn 2+ (2)-g-C 3 N 4-δ (10 mg) displays the highest photocatalytic activity toward eliminating tetracycline (TC, 10 mg L -1 , 50 mL), and the degradation efficiency (63.9%) within 30 min is 3.4 times that of g-C 3 N 4-δ (18.9%) irradiated by visible light. Moreover, the optimal composite demonstrates satisfactory recyclability and excellent universality. This study suggests a novel way to construct g-C 3 N 4 -based photocatalysts for efficiently degrading organic contaminants in water.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2019
·
IF 5.155
Jin Zhang,Yuyang Huang,Tao Nie,Rui Wang,Beibei He,Bo Han,Huanwen Wang,Yongshang Tian,Yansheng Gong
Herein, self-assembly of hierarchical multihole g-C 3 N 4 hexagon with excellent specific surface area (129 m 2 /g) and nitrogen vacancies were accomplished via a one-step polymerization of hydrothermal-treated dicyandiamide and ethylene-diamine-tetra-acetic acid (EDTA). The special chelate structure of EDTA efficiently enlarged a broad visible light response range, and the concentrations of EDTA promoted the self-assembly formation of different surface morphology . The photocatalytic H 2 production rate under visible light for the optimal g-C 3 N 4 hexagon (CN-20E) reaches 5839 μmol·g − 1 ·h − 1 and its apparent quantum efficiency reaches up to 7.3% at 420 nm, which has a 102 times higher for H 2 production rate than that of bulk g-C 3 N 4 (57 μmol·g − 1 ·h − 1 ). Special structure of the multihole hexagon endows them with remarkably visible light absorption, fast separation of photo-induced charge carriers, large surface areas as well as the exposure of potential photocatalytic active sites, thereby dramatically improved the H 2 production property. Moreover, the forming process for the specific structure and the reaction mechanism of the enhanced photocatalytic activity were proposed according to the experimental results and theoretical calculations. This work exhibits a new avenue to rehandle graphitic carbon nitride precursor to build a grafted structure for developing highly efficient g-C 3 N 4 in the practical photocatalytic application.
研究领域:
材料科学
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光催化技术
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能源化学
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产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2017
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IF 9.446
Jing Ding,Wei Xu,Hui Wan,Dashui Yuan,Chong Chen,Lei Wang,Guofeng Guan,Wei-Lin Dai
Vacancy defect in the semiconductors plays an important role in the improvement of the electronic structure and the increase of specific reaction sites for reactant molecules, and consequently enhancing the photocatalytic activity of semiconductor photocatalysts. Through high-temperature thermal condensation of a nitric acid-pretreated melamine precursor, nitrogen vacancies were successfully introduced in the framework of g-C 3 N 4 . The nitrogen vacancies located at the uncondensed terminal NH x lattice sites were conducive to the enhancement of optical absorption, the improvement of the separation efficiency of the photogenerated charge carrier and the increase of surface area, which was beneficial to the photocatalytic oxidation process. More significantly, the novel CNNA(X) were used as efficient photocatalysts in the green process of aromatic aldehydes from the photocatalytic selective oxidation of aromatic alcohols and the photocatalytic degradation of organic pollutants. CNNA(X) samples exhibited enhanced photocatalytic activity and excellent recyclability and stability. The 68.3% benzyl alcohol conversion and almost 100% selectivity was observed for the CNNA (0.9) photocatalyst, higher than that of pure g-C 3 N 4 . Meanwhile, CNNA (0.9) showed superior photocatalytic degradation performance of organic dyes (RhB and MO). Furthermore, the underlying photocatalytic oxidation mechanism was proposed by the controlled experiments using radical scavengers.
研究领域:
材料科学
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环境科学
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化学工程
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产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2022
·
IF 7.392
Xinran Li,Shuohan Li,Jian Xu,Lanxin Wang,Kaiwei Liang,Huihui Zhang,Xuelian Yu,Zhongwei Liu
Photoconversion of CO 2 into fuel is critical for realizing a net-zero emission future, but it remains an open challenge due to the unsatisfactory light absorption and photogenerated carriers’ separation efficiency of catalysts. In this work, upon in situ thermal polymerization method, the nanodiamond (ND) are homogeneously and solidly modified on the defective graphitic carbon nitride (g-C 3 N 4 ) surface. Under visible light irradiation, the ND/g-C 3 N 4 (NH) exhibits excellent CO 2 photocatalytic performance with a CO yield of 10.98 μmol/h (18.6 times higher than bulk g-C 3 N 4 ), predominant performance in the selectivity of CO and cyclic stability. The improved CO 2 photoreduction ability was sourced from the synergetic effect of nitrogen vacancies engineering and ND decoration, which also significantly improved visible light absorption capacity and facilitated electron transport pathways, and promoted the separation and transfer of charge carriers efficiently.
研究领域:
材料科学
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环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Zhihao Song,Lei Xu,Cheng Xie,Yanzhi Liu,Zhaohui Han,Junyu Lu
Visible light-driven photo-oxidation reactions hold significant potential for the treatment of gaseous pollutants. However, the weak internal electric field of carbon nitride (g-C 3 N 4 ) leads to sluggish migration of photogenerated carriers, while inefficient electron-hole pair separation further limits the overall photo-oxidation efficiency. In this study, nitrogen-vacancy (Nv) rich crystalline (Cs)/amorphous g-C 3 N 4 was synthesized using a two-step calcination method. The increased crystallinity facilitates faster carrier migration, broadens the potential difference between the crystalline and amorphous regions, and enhances the piezoelectric response. On the other hand, the incorporation of nitrogen vacancies (Nv) introduces asymmetry, generating a dipole field that significantly improves the efficiency of electron-hole pair separation. Moreover, the presence of NV improves the adsorption and activation of O 2 molecules, promoting the photo-oxidation of adsorbed NO via the generation of single linear oxygen ( 1 O 2 ). The resulting material, Cs-Nv-630, demonstrated excellent oxidative NO removal efficiency, achieving a removal rate of 95.3 % under visible light irradiation. This study highlights a novel strategy for enhancing photo-oxidation activity through structural engineering, leveraging crystallinity and dipole fields to optimize carrier migration and complexation.
研究领域:
材料科学
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环境科学
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化学
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产品关联
DOI
高影响因子
Surfaces and Interfaces
·
2025
·
IF 6.3
Yumin Zhang,Xin Ke,Wengang Liu
In this study, graphitic-phase carbon nitride (O-Nv-CN) photocatalysts with synergistically engineered nitrogen vacancies and oxygen doping were synthesized via hydrothermal reduction followed by high-temperature calcination. The incorporation of nitrogen vacancies modulated the electronic structure and promoted the separation of photogenerated charge carriers, while oxygen doping optimized the band alignment and extended the visible-light absorption range. These modifications jointly contributed to significantly enhanced photocatalytic performance. Material characterization revealed that O-Nv-CN exhibited thinner nanosheets and a more developed porous architecture compared to pristine g-C 3 N 4 , resulting in a higher specific surface area and an increased density of active sites, thereby improving pollutant adsorption and catalytic reactivity. Photocatalytic experiments demonstrated that O-Nv-CN achieved 2.4-fold and 4.5-fold improvements in the degradation efficiency and reaction rate of tetracycline hydrochloride (TC-HCl), respectively, relative to g-C 3 N 4 . Reactive species trapping experiments and electron spin resonance (ESR) analyses confirmed that •O 2 ⁻ and •OH were the dominant reactive species. Density functional theory (DFT) calculations further revealed that nitrogen vacancies and oxygen dopants synergistically restructured the electronic band configuration, thereby enhancing the adsorption and activation of O 2 and TC-HCl molecules. The material optimization strategy proposed in this study provides both a theoretical basis and experimental support for the removal of antibiotic contaminants in complex aqueous environments.
研究领域:
材料科学
·
环境科学
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理论计算
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DOI
高影响因子
危险品化学品经营许可证（带存储）