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Shaowen Cao Jingxiang Low Jiaguo Yu Mietek Jaroniec 《Advanced materials (Deerfield Beach, Fla.)》2015,27(13):2150-2176
Semiconductor‐based photocatalysis is considered to be an attractive way for solving the worldwide energy shortage and environmental pollution issues. Since the pioneering work in 2009 on graphitic carbon nitride (g‐C3N4) for visible‐light photocatalytic water splitting, g‐C3N4‐based photocatalysis has become a very hot research topic. This review summarizes the recent progress regarding the design and preparation of g‐C3N4‐based photocatalysts, including the fabrication and nanostructure design of pristine g‐C3N4, bandgap engineering through atomic‐level doping and molecular‐level modification, and the preparation of g‐C3N4‐based semiconductor composites. Also, the photocatalytic applications of g‐C3N4‐based photocatalysts in the fields of water splitting, CO2 reduction, pollutant degradation, organic syntheses, and bacterial disinfection are reviewed, with emphasis on photocatalysis promoted by carbon materials, non‐noble‐metal cocatalysts, and Z‐scheme heterojunctions. Finally, the concluding remarks are presented and some perspectives regarding the future development of g‐C3N4‐based photocatalysts are highlighted. 相似文献
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A Composite Polymeric Carbon Nitride with In Situ Formed Isotype Heterojunctions for Highly Improved Photocatalysis under Visible Light 下载免费PDF全文
Qinghua Liang Zhi Li Yu Bai Zheng‐Hong Huang Feiyu Kang Quan‐Hong Yang 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(9)
Introducing heterojunction is an effective way for improving the intrinsic photocatalytic activity of a graphitic carbon nitride (GCN) semiconductor. These heterostructures are mostly introduced by interfacing GCN with foreign materials that normally have entirely different physicochemical properties and show unfavorable compatibility, thus resulting in a limited improvement of the photocatalytic performance of the resultant materials. Herein, a composite polymeric carbon nitride (CPCN) that contains both melon‐based GCN and triazine‐based crystalline carbon nitride (CCN) is prepared by a simple thermal reaction between lithium chloride and GCN. Thanks to the intimate contact and good compatibility between GCN and CCN, an in situ formed heterojunction acts as a driving force for separating the photogenerated charge carriers in CPCN. As a result, CPCN exhibits a significantly improved photocatalytic performance under visible light irradiation, which is, respectively, 10.6 and 5.3 times as high as those of the GCN and CCN alone. This well designed isotype heterojunction by a coupling of CCN presents an effective avenue for developing efficient GCN photocatalysts. 相似文献
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Sulfur‐Modified Graphitic Carbon Nitride Nanostructures as an Efficient Electrocatalyst for Water Oxidation 下载免费PDF全文
Vinayak S. Kale Uk Sim Jiwoong Yang Kyoungsuk Jin Sue In Chae Woo Je Chang Arun Kumar Sinha Heonjin Ha Chan‐Cuk Hwang Junghyun An Hyo‐Ki Hong Zonghoon Lee Ki Tae Nam Taeghwan Hyeon 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(17)
There is an urgent need to develop metal‐free, low cost, durable, and highly efficient catalysts for industrially important oxygen evolution reactions. Inspired by natural geodes, unique melamine nanogeodes are successfully synthesized using hydrothermal process. Sulfur‐modified graphitic carbon nitride (S‐modified g‐CN x ) electrocatalysts are obtained by annealing these melamine nanogeodes in situ with sulfur. The sulfur modification in the g‐CN x structure leads to excellent oxygen evolution reaction activity by lowering the overpotential. Compared with the previously reported nonmetallic systems and well‐established metallic catalysts, the S‐modified g‐CN x nanostructures show superior performance, requiring a lower overpotential (290 mV) to achieve a current density of 10 mA cm?2 and a Tafel slope of 120 mV dec?1 with long‐term durability of 91.2% retention for 18 h. These inexpensive, environmentally friendly, and easy‐to‐synthesize catalysts with extraordinary performance will have a high impact in the field of oxygen evolution reaction electrocatalysis. 相似文献
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Jiafu Qu Dongyun Chen Najun Li Qingfeng Xu Hua Li Jinghui He Jianmei Lu 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(2)
A hard template method is used to prepare porous gold‐doped cerium and cobalt oxide (Au‐CexCoy) materials. A series of 3D Au‐Ce xCoy/graphene aerogel (GA) composites is then fabricated by a facile heating method. The obtained catalysts possess a well‐defined structure of ordered arrays of nanotubes and good performance in formaldehyde (HCHO) oxidation. The composition and surface elemental valence states of the catalysts are modulated by the Ce/Co molar ratio. The Au‐CexCoy catalyst and graphene oxide sheets are well compounded within 60 s through a diamine cross‐linker to form 3D Au‐CexCoy/GA composites. In addition, the resulting catalyst of 3 wt% Au‐Ce3Co/GA achieves ≈55% conversion at room temperature and 100% conversion when the reaction temperature is raised at 60 °C. The synergistic effect between CeO2 and Co3O4 promotes the migration of oxygen species and the activation of Au, which facilitates HCHO oxidation. The method used to prepare the 3D catalyst could be used to produce other catalytic materials with good replication of the template. In addition, these findings provide a simple method for rapid fabrication of catalyst/GA composites. The superior activity and stability of the 3D Au‐Ce3Co/GA catalyst make it potentially applicable in HCHO removal. 相似文献
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Daming Zhao Chung‐Li Dong Bin Wang Chao Chen Yu‐Cheng Huang Zhidan Diao Shuzhou Li Liejin Guo Shaohua Shen 《Advanced materials (Deerfield Beach, Fla.)》2019,31(43)
Electronic structure greatly determines the band structures and the charge carrier transport properties of semiconducting photocatalysts and consequently their photocatalytic activities. Here, by simply calcining the mixture of graphitic carbon nitride (g‐C3N4) and sodium borohydride in an inert atmosphere, boron dopants and nitrogen defects are simultaneously introduced into g‐C3N4. The resultant boron‐doped and nitrogen‐deficient g‐C3N4 exhibits excellent activity for photocatalytic oxygen evolution, with highest oxygen evolution rate reaching 561.2 µmol h?1 g?1, much higher than previously reported g‐C3N4. It is well evidenced that with conduction and valence band positions substantially and continuously tuned by the simultaneous introduction of boron dopants and nitrogen defects into g‐C3N4, the band structures are exceptionally modulated for both effective optical absorption in visible light and much increased driving force for water oxidation. Moreover, the engineered electronic structure creates abundant unsaturated sites and induces strong interlayer C–N interaction, leading to efficient electron excitation and accelerated charge transport. In the present work, a facile approach is successfully demonstrated to engineer the electronic structures and the band structures of g‐C3N4 with simultaneous introduction of dopants and defects for high‐performance photocatalytic oxygen evolution, which can provide informative principles for the design of efficient photocatalysis systems for solar energy conversion. 相似文献
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Yong Wang Peipei Du Hongzhe Pan Lin Fu Yu Zhang Jie Chen Youwei Du Nujiang Tang Gang Liu 《Advanced materials (Deerfield Beach, Fla.)》2019,31(40)
Atomically thin 2D carbon nitride sheets (CNS) are promising materials for photocatalytic applications due to their large surface area and very short charge‐carrier diffusion distance from the bulk to the surface. However, compared to their bulk counterpart, CNS' applications always suffer from an enlarged bandgap and thus narrowed solar absorption range. Here, an approach to significantly increase solar absorption of the atomically thin CNS via fluorination followed by thermal defluorination is reported. This approach can greatly increase the visible‐light absorption of CNS by extending the absorption edge up to 578 nm. The modulated CNS loaded with Pt cocatalyst as a photocatalyst shows a superior photocatalytic hydrogen production activity under visible‐light irradiation to Pt‐CNS. Combining experimental characterization with theoretical calculations shows that this approach can introduce cyano groups into the framework of CNS as well as the accompanied nitrogen vacancies at the edges, which leads to both narrowing the bandgap and changing the charge distribution. This study will provide an effective strategy to increase solar absorption of carbon‐nitride‐based photocatalysts for solar energy conversion applications. 相似文献
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Hadiseh Taheri Mehmet Altay Unal Melike Sevim Cansu Gurcan Okan Ekim Ahmet Ceylan Zois Syrgiannis Konstantinos C. Christoforidis Susanna Bosi Ozge Ozgen Manuel Jos Gmez Mine Turktas Erken igdem Soydal Zafer Erolu Ceylan Verda Bitirim Umut Cagin Fikret Ar Asuman Ozen Ozlem Kuuk Lucia Gemma Delogu Maurizio Prato
nder Metin Aelya Yilmazer 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(10)
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Alkali‐Assisted Synthesis of Nitrogen Deficient Graphitic Carbon Nitride with Tunable Band Structures for Efficient Visible‐Light‐Driven Hydrogen Evolution 下载免费PDF全文
Huijun Yu Run Shi Yunxuan Zhao Tong Bian Yufei Zhao Chao Zhou Geoffrey I. N. Waterhouse Li‐Zhu Wu Chen‐Ho Tung Tierui Zhang 《Advanced materials (Deerfield Beach, Fla.)》2017,29(16)
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Xing Zhi Yan Jiao Yao Zheng Shi‐Zhang Qiao 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(10)
Effective electrocatalysts are required for the CO2 reduction reaction (CRR), while the factors that can impact their catalytic activity are yet to be discovered. In this article, graphitic carbon nitride (g‐C3N4) is used to investigate the feasibility of regulating its CRR catalytic performance by interfacial electron transfer. A series of g‐C3N4/graphene with and without heteroatom doping (C3N4/XG, XG = BG, NG, OG, PG, G) is comprehensively evaluated for CRR through computational methods. Variable adsorption energetics and electronic structures are observed among different doping cases, demonstrating that a higher catalytic activity originates from more interfacial electron transfer. An activity trend is obtained to show the best catalytic performance of CRR to methane on C3N4/XG with an overpotential of 0.45 V (i.e., ?0.28 V vs reverse hydrogen electrode [RHE]). Such a low overpotential has never been achieved on any previously reported metallic CRR electrocatalysts, therefore indicating the availability of C3N4/XG for CO2 reduction and the applicability of electron transfer modulation to improve CRR catalytic performance. 相似文献
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以石墨相氮化碳(g-C3N4)和六水合硝酸钴为原料制备Co@CNT复合电磁波吸收剂,调节Co元素含量以提高其电磁波吸收性能。采用X射线衍射(XRD)、X射线光电子能谱(XPS)、拉曼光谱、扫描电镜(SEM)、能谱分析(EDS)和透射电镜(TEM)等手段表征其微结构和物相组成,使用矢量网络分析仪测量复合物电磁参数并进行Matlab模拟得到反射损耗图。结果表明,Co@CNT-1与石蜡质量比为1:3的材料,其吸波性能最优,厚度为4.1 mm时对电磁波的吸收最强,最小反射损耗(RLmin)为-45.5 dB;厚度仅为1.5 mm的材料,有效吸收带宽(RL<-10 dB)最大为4.42 GHz。 相似文献
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Dongni Liu Dongyun Chen Najun Li Qingfeng Xu Hua Li Jinghui He Jianmei Lu 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(31)
ZIF‐67‐derived 3D hollow mesoporous crystalline Co3O4 wrapped by 2D graphitic carbon nitride (g‐C3N4) nanosheets are prepared by low temperature annealing, and are used for the photocatalytic oxidation of nitric oxide (NO) at a concentration of 600 ppb. The p–n heterojunction between Co3O4 and g‐C3N4 forms a spatial conductive network frame and results in a broad visible light response range. The hollow mesoporous structure of Co3O4 contributes to the circulation and adsorption of NO, and the large specific surface area exposes abundant active sites for the reaction of active species. A maximum NO degradation efficiency of 57% is achieved by adjusting the mass of the Co3O4 precursor. Cycling tests and X‐ray diffraction indicate the high stability and recyclability of the composite, making it promising in environmental purification applications. 相似文献
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Drastic Enhancement of Photocatalytic Activities over Phosphoric Acid Protonated Porous g‐C3N4 Nanosheets under Visible Light 下载免费PDF全文
Li Shi Kun Chang Huabin Zhang Xiao Hai Liuqing Yang Tao Wang Jinhua Ye 《Small (Weinheim an der Bergstrasse, Germany)》2016,12(32):4431-4439
A simple method is developed to fabricate protonated porous graphitic carbon nitride nanosheets (P‐PCNNS) by protonation–exfoliation of bulk graphitic carbon nitride (BCN) with phosphoric acid (H3PO4). The H3PO4 treatment not only helps to exfoliate the BCN into 2D ultrathin nanosheets with abundant micro‐ and mesopores, endowing P‐PCNNS with more exposed active catalytic sites and cross‐plane diffusion channels to facilitate the mass and charge transport, but also induces the protonation of carbon nitride polymer, leading to the moderate removal of the impurities of carbon species in BCN for the optimization of the aromatic π‐conjugated system for better charge separation without changing its chemical structure. As a result, the P‐PCNNS show much higher photocatalytic performance for hydrogen evolution and CO2 conversion than bare BCN and graphitic carbon nitride nanosheets. 相似文献
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Guanchao Wang Ying Ma Ting Zhang Yuefeng Liu Baojun Wang Riguang Zhang Zhongkui Zhao 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(6):2205758
To develop a non-precious highly efficient cocatalyst to replace Pt on graphitic carbon nitride (g-C3N4) for solar H2 production is great significant, but still remains a huge challenge. The emerging single-atom catalyst presents a promising strategy for developing highly efficient non-precious cocatalyst owing to its unique adjustability of local coordination environment and electronic structure. Herein, this work presents a facile approach to achieve single Ni sites (Ni1-N2S) with unique local coordination structure featuring one Ni atom coordinated with two nitrogen atoms and one sulfur atom, confirmed by high-angle annular dark-field scanning transmission electron microscopy, X-ray absorption spectroscopy, and density functional theory calculation. Thanks to the unique electron structure of Ni1-N2S sites, the 1095 µmol g−1 h−1 of high H2 evolution rate with 4.1% of apparent quantum yield at 420 nm are achieved. This work paves a pathway for designing a highly efficient non-precious transition metal cocatalyst for photocatalytic H2 evolution. 相似文献
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Dibenzothiophene‐S,S‐Dioxide‐Based Conjugated Polymers: Highly Efficient Photocatalyts for Hydrogen Production from Water under Visible Light 下载免费PDF全文
Chunhui Dai Shidang Xu Wei Liu Xuezhong Gong Majid Panahandeh‐Fard Zitong Liu Deqing Zhang Can Xue Kian Ping Loh Bin Liu 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(34)
Three dibenzothiophene‐S,S‐dioxide‐based alternating copolymers were synthesized by facile Suzuki polymerization for visible light–responsive hydrogen production from water (> 420 nm). Without addition of any cocatalyst, FluPh2‐SO showed a photocatalytic efficiency of 3.48 mmol h?1 g?1, while a larger hydrogen evolution rate (HER) of 4.74 mmol h?1 g?1 was achieved for Py‐SO, which was ascribed to the improved coplanarity of the polymer that facilitated both intermolecular packing and charge transport. To minimize the possible steric hindrance of FluPh2‐SO by replacing 9,9′‐diphenylfluorene with fluorene, Flu‐SO exhibited a more red‐shifted absorption than FluPh2‐SO and yielded the highest HER of 5.04 mmol h?1 g?1. This work highlights the potential of dibenzothiophene‐S,S‐dioxide as a versatile building block and the rational design strategy for achieving high photocatalytic efficiency. 相似文献
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Hadiseh Taheri Mehmet Altay Unal Melike Sevim Cansu Gurcan Okan Ekim Ahmet Ceylan Zois Syrgiannis Konstantinos C. Christoforidis Susanna Bosi Ozge Ozgen Manuel Jos Gmez Mine Turktas Erken igdem Soydal Zafer Erolu Ceylan Verda Bitirim Umut Cagin Fikret Ar Asuman Ozen Ozlem Kuuk Lucia Gemma Delogu Maurizio Prato
nder Metin Aelya Yilmazer 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(10)
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Photocatalysis: Alkali‐Assisted Synthesis of Nitrogen Deficient Graphitic Carbon Nitride with Tunable Band Structures for Efficient Visible‐Light‐Driven Hydrogen Evolution (Adv. Mater. 16/2017) 下载免费PDF全文
Huijun Yu Run Shi Yunxuan Zhao Tong Bian Yufei Zhao Chao Zhou Geoffrey I. N. Waterhouse Li‐Zhu Wu Chen‐Ho Tung Tierui Zhang 《Advanced materials (Deerfield Beach, Fla.)》2017,29(16)