Carbon nitride (CN x ) is a light-absorber with excellent performance in photocatalytic suspension systems, but the activity of CN x photoelectrodes has remained low. Here, cyanamide-functionalized CN x ( NCN CN x ) was co-deposited with ITO nanoparticles on a 1.8 Å thick alumina-coated FTO electrode. Transient absorption spectroscopy and impedance measurements support that ITO acts as a conductive binder and improves electron extraction from the NCN CN x , whilst the alumina underlayer reduces recombination losses between the ITO and the FTO glass. The Al 2 O 3 j ITO : NCN CN x film displays a benchmark performance for CN x -based photoanodes with an onset of À 0.4 V vs a reversible hydrogen electrode (RHE), and 1.4 � 0.2 mA cm À 2 at 1.23 V vs RHE during AM1.5G irradiation for the selective oxidation of 4-methylbenzyl alcohol. This assembly strategy will improve the exploration of CN x in fundamental and applied photoelectrochemical (PEC) studies.
Two series of novel carbon nitride photocatalysts, Rho‐CN (“rhodizonate‐doped carbon nitride”) and Rho‐CN‐TC (Rho‐CN treated in potassium thiocyanate melt), are synthesized in a multistep fashion via copolymerization of cyanamide with potassium rhodizonate. The formed ionic carbon nitrides are composed of poly(triazine imide) (PTI/Li+Cl−) and potassium poly(heptazine imide) (K‐PHI) phases and provide a broad absorption range up to 800 nm. The photocatalysts are characterized by several techniques (including diffuse reflectance ultraviolet–visible, powder X‐ray diffraction, Fourier transform infrared, scanning electron microscopy, and electrochemical methods) and studied in a series of photocatalytic reactions, including red light‐promoted benzylamine oxidation, dual photoredox/nickel C–N cross‐coupling, and hydrogen peroxide evolution. The optimal ratio of rhodizonate dopant in its mixture with cyanamide is found to be 0.5 mol%. The performance of the newly synthesized materials is comparable to the activities of the benchmark catalysts K‐PHI and CN‐OA‐m (defective poly(heptazine imide) doped with oxamide), while not requiring more expensive nitrogen sources for preparation, like 5‐aminotetrazole, or multiple oven cycles.
Carbon nitride (CN x ) is a light-absorber with excellent performance in photocatalytic suspension systems, but the activity of CN x photoelectrodes has remained low. Here, cyanamide-functionalized CN x ( NCN CN x ) was co-deposited with ITO nanoparticles on a 1.8 Å thick alumina-coated FTO electrode. Transient absorption spectroscopy and impedance measurements support that ITO acts as a conductive binder and improves electron extraction from the NCN CN x , whilst the alumina underlayer reduces recombination losses between the ITO and the FTO glass. The Al 2 O 3 j ITO : NCN CN x film displays a benchmark performance for CN x -based photoanodes with an onset of À 0.4 V vs a reversible hydrogen electrode (RHE), and 1.4 � 0.2 mA cm À 2 at 1.23 V vs RHE during AM1.5G irradiation for the selective oxidation of 4-methylbenzyl alcohol. This assembly strategy will improve the exploration of CN x in fundamental and applied photoelectrochemical (PEC) studies.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.