Ultrathin Crystalline Covalent‐Triazine‐Framework Nanosheets with Electron Donor Groups for Synergistically Enhanced Photocatalytic Water Splitting

Abstract

Ultrathin nanosheets have great potential for photocatalytic applications,however,suffer from enlarged band gap and narrowed visible-light-responsive range due to the quantum confinement effect. Herein, we report an ovel redox strategy for efficient preparation of ultrathin crystalline amidefunctionalizedc ovalent-triazine-framework nanosheets (CTF NSs) with enhanced visible light absorption. The CTF NSs exhibited photocatalytic hydrogen (512.3 mmol h À1 )a nd oxygen (12.37 mmol h À1 )e volution rates much higher than that of pristine bulk CTF.Photocatalytic overall water splitting could be achieved with efficient stoichiometric H 2 (5.13 mmol h À1 ) and O 2 (2.53 mmol h À1 )e volution rates under visible light irradiation. Experimental and theoretical analysis revealed that introduction of amide groups as electron donor optimized the band structure and improve its visible-light absorption, hydrophilicity and carrier separation efficiency,thus resulting in the enhanced photocatalytic performance.The well-dispersed CTF NSs could be easily cast onto asupport as athin film device and demonstrate excellent photocatalytic activity (25.7 mmol h À1 m À2 for hydrogen evolution).

Semicrystalline SrTiO3‐Decorated Anatase TiO2 Nanopie as Heterostructure for Efficient Photocatalytic Hydrogen Evolution

“…Approaches including size optimization, structural modification and surface design have been explored to accelerate the separation rate of electron-hole pairs and optimize the photocatalytic performance. [5][6][7] Among these works, creating nanosized heterostructure is of special attraction for its possibility of tuning the interfacial band bending resulting from the internal electric field and shortening the migration path of photogenerated electrons and holes due to the close contact and proper band edge coupling. [8,9] Further downsizing the dimensions of components is regarded as a promising strategy to create abundant contact interface regions for nano-heterostructures.…”

Tunable Carrier Transfer of Polymeric Carbon Nitride with Charge-Conducting CoV2O6∙2H2O for Photocatalytic O2 Evolution

“…Furthermore, a high-resolution XPS analysis of C 1s and N 1s belonging to PCN was also carried out, as seen in Figure 3 e. The peaks of C 1s can be divided into two peaks at binding energies of 288.0 and 284.7 eV, respectively. The former was assigned to the sp 2 hybridized carbon of the triazine ring (N–C=N) of PCN and the latter was assigned to the C=C group of PCN [ 35 , 39 ]. In Figure 3 f, four peaks of N 1s can be observed.…”

2D Polymer Nanosheets for Membrane Separation

“…[ 15 ] The top–down strategy usually utilizes external forces to directly break the weak interactions between the adjacent layers of polymers so that multi‐/mono‐layer polymer nanosheets can be successfully achieved. So far, the well‐developed exfoliation methods generally include the liquid phase exfoliation (LPE), [ 16 , 17 , 18 , 19 ] chemical exfoliation, [ 20 , 21 , 22 , 23 ] and mechanical exfoliation, [ 24 , 25 , 26 ] all of which have been used to obtain ultrathin 2D polymer nanosheets.…”