3D Foam Strutted Graphene Carbon Nitride with Highly Stable Optoelectronic Properties

Abstract

Controlled morphology modulation of graphene carbon nitride (g-C 3 N 4 ) is successfully realized from bulk to 3D loose foam architecture via the blowing effect of a bubble, which can be controlled by heating rate. The loose foam network is comprised by spatially scaffolded few-atom-layer interconnected flakes with the large specific surface area, as supporters to prevent agglomeration and provide a pathway for electron/phonon transports. The photocatalytic performance of 3D foam strutted g-C 3 N 4 toward RhB decomposition and hydrogen evolution is significantly enhanced with the morphology optimization while its excellent optoelectronic properties are maintained simultaneously. Herein, the ultrathin, mono-, and high-quality foam g-C 3 N 4 interconnected flakes with controlled layer are facilely obtained through ultrasonic, thus overcoming the drawbacks of a traditional top-down approach, opening a wide horizon for diverse practical usages. Additionally, the layer control mechanism of 3D hierarchical structure has been explored by means of bubble growth kinetics analysis and the density functional theory calculations.

Confining the polymerization degree of graphitic carbon nitride in porous zeolite-Y and its luminescence

“…7 (a-c) The normalized PL emission spectra of the CN indicate the formation of graphite structure in bulk g-C 3 N 4 . 20,45,46 The melamine has two ngerprint peaks located at around 675 cm À1 (triazine ring breathing mode) and 1558 cm À1 (NH 2 bending mode), respectively. 47,48 These two peaks disappear for the CN r -Y (r ¼ 1.2, 1.4, 2.0) samples, implying that the melamine has been nished aer the polymerization reaction.…”

Full‐Color Chemically Modulated g‐C3N4 for White‐Light‐Emitting Device

“…Time‐resolved emission spectra were carried out to gain insight into the effect of defect‐related states on tuning the radiatively relaxed transition, choosing pristine g‐C 3 N 4 (blue), CNS 0.01 (yellow), and CNS 0.05 (orange) as model samples for investigation. The emission centers of pristine g‐C 3 N 4 were located at ≈430 and 470 nm, originated from the transition of δ*→LP and π*→LP, respectively (Figure e) . Upon low‐content molecular doping (CNS 0.01 ), a new emission center at 510 nm is detected as dominant peak while the intrinsic emissions of ≈430 and 470 nm are weakened, indicating the creation of intermediate states form below the π* states during the modification process (Figure f).…”

“…To explain the tunable PL emission mechanisms of thiophene‐doped g‐C 3 N 4 , DFT calculations were performed to study the modulation electronic properties by the doping of the strong electron donor groups. Theoretical calculations indicated that the PL emission of g‐C 3 N 4 products are determined by the photoinduced electron radiative transition from CB to VB, related to the lowest unoccupied molecular orbital (LUMO) of CN bond orbitals in the π‐conjugated system, and the highest occupied molecular orbital (HOMO) of an LP in the N 2p orbitals ( Figure a), respectively . The incorporation of the thiophene‐conjugated system into the tri‐s‐triazine‐conjugated structure can efficiently relocalize the π electrons by the effect of its electron‐donating characteristics, resulting in the stronger π electron delocalization within the sp 2 domain.…”

Engineering Amorphous Carbon onto Ultrathin g‐C3N4 to Suppress Intersystem Crossing for Efficient Photocatalytic H2 Evolution

“…In all the samples, there were two characteristic diffraction peaks positioned at 13.0° and 27.8°, with the strong characteristic peak at 27.8°, which was indexed to the (0 0 2) planes of g‐C 3 N 4 , corresponding to the interlayer‐stacking of the conjugated aromatic system, indicating that the thus‐formed nanocomposites possess layered structures . The peak intensity of our samples was obviously weaker than that of the bulk g‐C 3 N 4 , which is caused by the reduced length of interlayer periodicity . In addition, the weak diffraction peak at 13.0° was ascribed to the (1 0 0) diffraction of g‐C 3 N 4 , suggesting that the tris‐triazine units exhibit graphitic layered stacking …”