scholarly journals Graphitic Carbon Nitride for Photocatalytic Air Treatment

Materials ◽  
2020 ◽  
Vol 13 (13) ◽  
pp. 3038
Author(s):  
Michal Baudys ◽  
Šárka Paušová ◽  
Petr Praus ◽  
Vlasta Brezová ◽  
Dana Dvoranová ◽  
...  
Keyword(s):  
Uv Irradiation ◽  
Environmental Remediation ◽  
Carbon Nitride ◽  
Electronic Band Structure ◽  
Graphitic Carbon ◽  
Graphitic Carbon Nitride ◽  
Paramagnetic Resonance ◽  
Electronic Band ◽  
Acetaldehyde Oxidation ◽  
Earth Abundant

Graphitic carbon nitride (g-C3N4) is a conjugated polymer, which recently drew a lot of attention as a metal-free and UV and visible light responsive photocatalyst in the field of solar energy conversion and environmental remediation. This is due to its appealing electronic band structure, high physicochemical stability and earth-abundant nature. In the present work, bulk g-C3N4 was synthesized by thermal decomposition of melamine. This material was further exfoliated by thermal treatment. S-doped samples were prepared from thiourea or further treatment of exfoliated g-C3N4 by mesylchloride. Synthesized materials were applied for photocatalytic removal of air pollutants (acetaldehyde and NOx) according to the ISO 22197 and ISO 22197-1 methodology. The efficiency of acetaldehyde removal under UV irradiation was negligible for all g-C3N4 samples. This can be explained by the fact that g-C3N4 under irradiation does not directly form hydroxyl radicals, which are the primary oxidation species in acetaldehyde oxidation. It was proved by electron paramagnetic resonance (EPR) spectroscopy that the dominant species formed on the irradiated surface of g-C3N4 was the superoxide radical. Its production was responsible for a very high NOx removal efficiency not only under UV irradiation (which was comparable with that of TiO2), but also under visible irradiation.

Improving the photocatalytic activity of s-triazine based graphitic carbon nitride through metal decoration: an ab initio investigation

2016 ◽  
Vol 18 (38) ◽  
pp. 26466-26474 ◽  
Author(s):  
K. Srinivasu ◽  
Brindaban Modak ◽  
Swapan K. Ghosh
Keyword(s):  
Photocatalytic Activity ◽  
Density Functional ◽  
Carbon Nitride ◽  
Electronic Band Structure ◽  
Density Functional Theory Calculations ◽  
Graphitic Carbon ◽  
Graphitic Carbon Nitride ◽  
Electronic Band ◽  
Solar Water Splitting ◽  
Metal Decoration

Through density functional theory calculations, we attempted to tune the electronic band structure of poly s-triazine based graphitic carbon nitride by decorating it with different metal atoms and clusters for improving its photocatalytic activity towards solar water splitting.

Graphene/graphitic carbon nitride hybrids for catalysis

2017 ◽  
Vol 4 (5) ◽  
pp. 832-850 ◽  
Author(s):  
Qing Han ◽  
Nan Chen ◽  
Jing Zhang ◽  
Liangti Qu
Keyword(s):  
Mechanical Properties ◽  
Carbon Nitride ◽  
Electronic Band Structure ◽  
Graphitic Carbon ◽  
Graphitic Carbon Nitride ◽  
Large Specific Surface Area ◽  
Thermal And Mechanical Properties ◽  
Electronic Band ◽  
Physicochemical Stability ◽  
Photochemical Catalysis

Benefiting from the large specific surface area, outstanding electronic, optical, thermal and mechanical properties of graphene, as well as the exceptional electronic band structure and good physicochemical stability of graphitic carbon nitride (g-C3N4), graphene/g-C3N4hybrids present great potential in electrochemical and photochemical catalysis.

scholarly journals Graphitic Carbon Nitride-Based Composite in Advanced Oxidation Processes for Aqueous Organic Pollutants Removal: A Review

Processes ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 66
Author(s):  
Yu Shen ◽  
Antonio J. Dos santos-Garcia ◽  
María José Martín de Vidales
Keyword(s):  
Organic Pollutants ◽  
Advanced Oxidation Processes ◽  
Carbon Nitride ◽  
Electronic Band Structure ◽  
Advanced Oxidation ◽  
Graphitic Carbon ◽  
Graphitic Carbon Nitride ◽  
Electronic Band ◽  
Oxidation Processes ◽  
Pollutants Removal

In recent decades, a growing number of organic pollutants released have raised worldwide concern. Graphitic carbon nitride (g-C3N4) has drawn increasing attention in environmental pollutants removal thanks to its unique electronic band structure and excellent physicochemical stability. This paper reviews the recent progress of g-C3N4-based composites as catalysts in various advanced oxidation processes (AOPs), including chemical, photochemical, and electrochemical AOPs. Strategies for enhancing catalytic performance such as element-doping, nanostructure design, and heterojunction construction are summarized in detail. The catalytic degradation mechanisms are also discussed briefly.

Carbon nitride as a new way to facilitate the next generation of carbon-based supercapacitors

2019 ◽  
Vol 3 (9) ◽  
pp. 2176-2204 ◽  
Author(s):  
Mostafa Ghaemmaghami ◽  
Rahim Mohammadi
Keyword(s):  
Energy Storage ◽  
Carbon Nitride ◽  
Graphitic Carbon ◽  
Graphitic Carbon Nitride ◽  
Energy Storage And Conversion ◽  
Next Generation ◽  
Earth Abundant ◽  
New Research ◽  
Carbon Based

As an earth-abundant material, graphitic carbon nitride has become a new research hotspot and drawn broad interdisciplinary attention in the area of energy storage and conversion and it showed great potential for application in supercapacitors.

scholarly journals 2D/2D layered nano-heterostructures of transition metal dichalcogenides (MS2, M = Mo, Sn) and graphitic carbon nitride (g-C3N4) for photocatalytic hydrogen production and environmental remediation

2021 ◽  
Author(s):  
Ειρήνη Κουτσουρούμπη
Keyword(s):  
Hydrogen Production ◽  
Transition Metal ◽  
Environmental Remediation ◽  
Carbon Nitride ◽  
Transition Metal Dichalcogenides ◽  
Graphitic Carbon ◽  
Graphitic Carbon Nitride ◽  
Photocatalytic Hydrogen Production ◽  
Metal Dichalcogenides

Οι εξαιρετικά αποδοτικοί και οικονομικά αποδοτικοί φωτοκαταλύτες είναι από τους πιο σημαντικούς στόχους στον τομέα της παραγωγής καθαρής ενέργειας και της περιβαλλοντικής αποκατάστασης. Για να κατανοήσουμε τους μηχανισμούς φωτοχημικής μεταφοράς φορτίου στη νανοκλίμακα, είναι απαραίτητο να αναπτυχθούν καταλύτες υψηλής αποτελεσματικότητας. Η παρούσα διδακτορική διατριβή επικεντρώνεται στην επιτυχή ανάπτυξη μιας νέας συνθετικής στρατηγικής για την προετοιμασία 2D/2D πολυεπίπεδων νανο-ετεροδομών διχαλκογονιδίων μετάλλων μετάπτωσης (MS2, M = Mo, Sn) και γραφιτικού νιτριδίου του άνθρακα (g-C3N4) για εφαρμογές στην φωτοκαταλυτική παραγωγή καυσίμων και περιβαλλοντική αποκατάσταση . Σε αυτό το πλαίσιο, ο ορθολογικός σχεδιασμός νέων φωτοχημικών συστημάτων μας οδήγησε στη σύνθεση πολυεπίπεδων ετεροδομών με την εναπόθεση νανοφυλλών MoS2 με μεταβλητά πλευρικά μεγέθη στην επιφάνεια του g-C3N4. Αυτές οι σύνθετες δομές μελετήθηκαν ως καθοδικοί καταλύτες για φωτοκαταλυτική παραγωγή υδρογόνου από νερό υπό υπεριώδη ακτινοβολία και ορατό φως. Γενικά, ο φωτοχημικός διαχωρισμός του νερού για την παραγωγή υδρογόνου είναι μια πολύ ελκυστική και πολλά υποσχόμενη λύση στην ενεργειακή κρίση και στο πρόβλημα της κλιματικής αλλαγής. Αυτή η διαδικασία περιλαμβάνειτην αναγωγή των πρωτονίων του νερού σε μοριακό υδρογόνο στην επιφάνεια ενός ημιαγώγιμου καταλύτη. Από την άλλη πλευρά, τα περιβαλλοντικά προβλήματα των υδάτων οφείλονται κυρίως στη ρύπανση του νερού που προκαλείται από ιδιαίτερα τοξικά και καρκινογόνα μεταλλικά ιόντα, όπως το εξασθενές χρώμιο (Cr(VI)). Για το λόγο αυτό, καταφέραμε να συνθέσουμε νανο-ετεροδομές MoS2/g-C3N4 ντοπαρισμένες με Ni, καθώς και νανο-ετεροδομές SnS2/g-C3N4 που επιδεικνύουν υψηλή φωτοκαταλυτική δράση στην αναγωγή του Cr(VI) στην πολύ λιγότερο τοξική μορφή χρωμίου, Cr(III). Ένα αξιοσημείωτο σημείο αυτών των καταλυτικών συστημάτων είναι ότι όλες οι αντιδράσεις φωτοχημικής αναγωγής πραγματοποιήθηκαν σε υδατικά διαλύματα Cr(VI) χωρίς την παρουσία θυσιαζόμενων ενώσεων ως δοτών ηλεκτρονίων. Όλες οι παραπάνω ετεροσυνδέσεις μπορούν να διευκολύνουν τον υψηλό ρυθμό διαχωρισμού και μεταφοράς των φωτοεπαγόμενων φορέων φορτίου, επιδεικνύοντας βελτιωμένη καταλυτική συμπεριφορά έναντι των μακροσκοπικών αναλόγων τους στην παραγωγή υδρογόνου καθώς και στην αναγωγή του εξασθενούς χρωμίου. Οι φωτοκαταλυτικές αντιδράσεις πραγματοποιήθηκαν με τη χρήση οικονομικά αποδοτικών και φιλικών προς το περιβάλλον αντιδραστηρίων και τη χρήση ανανεώσιμων πηγών ενέργειας για την επίλυση βασικών ενεργειακών και περιβαλλοντικών προκλήσεων.

scholarly journals Nitrogen-doped Carbon Nanospheres-Modified Graphitic Carbon Nitride with Outstanding Photocatalytic Activity

2020 ◽  
Vol 12 (1) ◽  
Author(s):  
Qiaoran Liu ◽  
Hao Tian ◽  
Zhenghua Dai ◽  
Hongqi Sun ◽  
Jian Liu ◽  
...  
Keyword(s):  
Environmental Remediation ◽  
Density Functional ◽  
Carbon Nitride ◽  
Graphitic Carbon ◽  
Graphitic Carbon Nitride ◽  
Carbon Nanospheres ◽  
Electron Hole ◽  
Practical Applications ◽  
Nitrogen Doped ◽  
Nitrogen Doped Carbon

AbstractMetals and metal oxides are widely used as photo/electro-catalysts for environmental remediation. However, there are many issues related to these metal-based catalysts for practical applications, such as high cost and detrimental environmental impact due to metal leaching. Carbon-based catalysts have the potential to overcome these limitations. In this study, monodisperse nitrogen-doped carbon nanospheres (NCs) were synthesized and loaded onto graphitic carbon nitride (g-C3N4, GCN) via a facile hydrothermal method for photocatalytic removal of sulfachloropyridazine (SCP). The prepared metal-free GCN-NC exhibited remarkably enhanced efficiency in SCP degradation. The nitrogen content in NC critically influences the physicochemical properties and performances of the resultant hybrids. The optimum nitrogen doping concentration was identified at 6.0 wt%. The SCP removal rates can be improved by a factor of 4.7 and 3.2, under UV and visible lights, by the GCN-NC composite due to the enhanced charge mobility and visible light harvesting. The mechanism of the improved photocatalytic performance and band structure alternation were further investigated by density functional theory (DFT) calculations. The DFT results confirm the high capability of the GCN-NC hybrids to activate the electron–hole pairs by reducing the band gap energy and efficiently separating electron/hole pairs. Superoxide and hydroxyl radicals are subsequently produced, leading to the efficient SCP removal.

scholarly journals Dual-defect-modified graphitic carbon nitride with boosted photocatalytic activity under visible light

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Hideyuki Katsumata ◽  
Fumiya Higashi ◽  
Yuya Kobayashi ◽  
Ikki Tateishi ◽  
Mai Furukawa ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Environmental Remediation ◽  
Carbon Nitride ◽  
Order Rate Constant ◽  
Graphitic Carbon ◽  
Graphitic Carbon Nitride ◽  
Strong Electron ◽  
Efficient Charge

Abstract The development of photocatalysts that efficiently degrade organic pollutants is an important environmental-remediation objective. To that end, we report a strategy for the ready fabrication of oxygen-doped graphitic carbon nitride (CN) with engendered nitrogen deficiencies. The addition of KOH and oxalic acid during the thermal condensation of urea led to a material that exhibits a significantly higher pseudo-first-order rate constant for the degradation of bisphenol A (BPA) (0.0225 min−1) compared to that of CN (0.00222 min−1). The enhanced photocatalytic activity for the degradation of BPA exhibited by the dual-defect-modified CN (Bt-OA-CN) is ascribable to a considerable red-shift in its light absorption compared to that of CN, as well as its modulated energy band structure and more-efficient charge separation. Furthermore, we confirmed that the in-situ-formed cyano groups in the Bt-OA-CN photocatalyst act as strong electron-withdrawing groups that efficiently separate and transfer photo-generated charge carriers to the surface of the photocatalyst. This study provides novel insight into the in-situ dual-defect strategy for g-C3N4, which is extendable to the modification of other photocatalysts; it also introduces Bt-OA-CN as a potential highly efficient visible-light-responsive photocatalyst for use in environmental-remediation applications.

Sign in / Sign up

Export Citation Format

Share Document