Metal‐Free 2D/2D Heterojunction of Graphitic Carbon Nitride/Graphdiyne for Improving the Hole Mobility of Graphitic Carbon Nitride

Abstract

The design and synthesis of efficient metal‐free photoelectrocatalysts for water splitting are of great significance, as nonmetal elements are generally earth abundant and environment friendly. As a typical metal‐free semiconductor, g‐C3N4 has received much attention in the field of photocatalytic water splitting. However, the poor photoinduced hole mobility of g‐C3N4 restrains its catalytic performance. Herein, for the first time, graphdiyne (GDY) is used to interact with g‐C3N4 to construct a metal‐free 2D/2D heterojunction of g‐C3N4/GDY as an efficient photoelectrocatalyst for water splitting. The g‐C3N4/GDY photocathode exhibits enhanced photocarriers separation due to excellent hole transfer nature of graphdiyne and the structure of 2D/2D heterojunction of g‐C3N4/GDY, realizing a sevenfold increase in electron life time (610 μs) compared to that of g‐C3N4 (88 μs), and a threefold increase in photocurrent density (−98 μA cm−2) compared to that of g‐C3N4 photocathode (−32 μA cm−2) at a potential of 0 V versus normal hydrogen electrode (NHE) in neutral aqueous solution. The photoelectrocatalytic performance can be further improved by fabricating Pt@g‐C3N4/GDY, which displays an photocurrent of −133 μA cm−2 at a potential of 0 V versus NHE in neutral aqueous solution. This work provides a new strategy for the design of efficient metal‐free photoelectrocatalysts for water splitting.

Graphdiyne: A New Photocatalytic CO2 Reduction Cocatalyst

“…solar irradiation is recognized as a potential solution to these issues. [36] Motivated by the multiple merits of GDY, we herein report a GDY decorated TiO 2 heterojunction prepared by electrostatic driven self-assembly of TiO 2 nanofibers and GDY nanosheets for photocatalytic CO 2 reduction. …”

“…Recently, graphdiyne (GDY) is emerging as a unique 2D carbon material, consisting of aromatic rings made by sp-and sp 2 -carbon and carbon-carbon triple bonds linked by an acetylenic linkage. [36] Motivated by the multiple merits of GDY, we herein report a GDY decorated TiO 2 heterojunction prepared by electrostatic driven self-assembly of TiO 2 nanofibers and GDY nanosheets for photocatalytic CO 2 reduction. [34,35] More importantly, electrons in the high-energy acetylenic linkages are prone to delocalization to reach the most stable state.…”

Graphitic Carbon Nitride with Dopant Induced Charge Localization for Enhanced Photoreduction of CO2 to CH4

“…[8][9][10] Although many studies have been widely carried out, its CO 2 reduction performance is still far from the actual application requirements and the product is mainly CO (2-electron reduction product), [11,12] due to the high recombination rate of charge carriers and low reaction dynamics. [13][14][15][16] It is well known that electrons are generally excited from N atoms to C atoms in g-C 3 N 4 . Moreover, the electrons are mainly localized around N, especially the twocoordinated N atoms, which have been considered as the active sites for photocatalytic reaction.…”

Kohlenstoffnitridmaterialien für photochemische Zellen zur Wasserspaltung

“…[77,79,[95][96][97][98] Zum Schluss diskutieren wir kurz CN-basierte Elektroden in anderen photogetriebenen Anwendungen. An dieser Stelle sei darauf hingewiesen, dass CN auch als die photoaktive Komponente einer Photokathode dienen kann.…”