Freeze-dried dicyandiamide-derived g-C3N4 as an effective photocatalyst for H2 generation

Metallic plasmons significantly boosted visible-light photocatalytic hydrogen evolution from water splitting

“…Polymeric g-C 3 N 4 is attractive as compared to conventional semiconductors, owing to its remarkable photocatalytic stability, easy synthesis, narrow bandgap, and capability of visible-light absorption. [13][14][15] Moreover, g-C 3 N 4 is considered as a rich polymer source and readily synthesized by direct calcination of cheap, nitrogen-rich, and reliable compounds, in particular urea, 16 thiourea, 17 dicyanamide, 18,19 and melamine. 20 Despite its advantages, bare g-C 3 N 4 appears to be restricted in terms of low photocatalytic efficiency and applicability because of poor light absorption and fast a Division of Nanomaterials and Chemistry, Hefei National Research Center for Physical Sciences at the Microscale, The First Affiliated Hospital, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China.…”

Optimizing dicyandiamide pretreatment conditions for enhanced structure and electronic properties of polymeric graphitic carbon nitride

“…For instance, Hu et al have investigated freeze drying process to obtain complete polymerization of heptazine units of g-C 3 N 4 . 29 In a similar study, Li et al explored the possibility of synthesizing gCN using a rapid recrystallization process. These studies revealed that simple recrystallization processes circumvent the need for the addition of a carbon source and amplify the PEC performance.…”

“…A pretreatment approach could have a direct influence on the final morphologies, solid yield, and C/N compositions of the synthesized systems, characteristics that can influence the corresponding electronic properties with a direct impact on potential electrochemical or catalytic applications of these materials. 29,33 Briefly, DCDA (1 g) was weighed and added in a 50 mL crucible covered with the lid. The DCDA-filled crucible was then placed at the center of a quartz tube and heated in a tube furnace (Thermo Scientific Lindberg/Blue M TF55035C Tube Furnace) at 550 1C for 2 h in the presence of an argon atmosphere.…”

Gel-like Ag-Dicyandiamide Metal–Organic Supramolecular Network-Derived g-C3N4 for Photocatalytic Hydrogen Generation

“…Recently, we reported that freeze-dried dicyandiamide is advantageous for crystallization and subsequent thermal condensation to produce heptazine-based g-C 3 N 4 with enhanced H 2 evolution. 28 However, metal-incorporated freeze-dried MOSN-derived g-C 3 N 4 using dicyandiamide as a precursor for photocatalytic H 2 production has never been reported. In this study, Ag and dicyandiamide were used to prepare a metal−organic supramolecule because Ag metal exhibits a surface plasmon resonance (SPR) effect that effectively induces electron transfer at the metal−semiconductor interface; 29,30 the cyano group of dicyandiamide can be easily conjugated with Ag + according to the following equation 31…”

“…With regard to the synthesis of g-C 3 N 4 , thermal condensation has been widely employed, but very few studies have been reported on the use of metal–organic supramolecules to prepare g-C 3 N 4 . Recently, we reported that freeze-dried dicyandiamide is advantageous for crystallization and subsequent thermal condensation to produce heptazine-based g-C 3 N 4 with enhanced H 2 evolution . However, metal-incorporated freeze-dried MOSN-derived g-C 3 N 4 using dicyandiamide as a precursor for photocatalytic H 2 production has never been reported.…”