Tailor‐Engineered 2D Cocatalysts: Harnessing Electron–Hole Redox Center of 2D g‐C<sub>3</sub>N<sub>4</sub> Photocatalysts toward Solar‐to‐Chemical Conversion and Environmental Purification (Adv. Funct. Mater. 29/2022)

Although challenges remain, synergistic adjusting various microstructures and photo/electrochemical parameters of graphitic carbon nitride (g‐C3N4) in photocatalytic hydrogen evolution reaction (HER) are the keys to alleviating the energy crisis and environmental pollution. In this work, a novel nitrogen‐defective and sulfur‐doped g‐C3N4 (S‐g‐C3N4‐D) is designed elaborately. Subsequent physical and chemical characterization proved that the developed S‐g‐C3N4‐D not only displays well‐defined 2D lamellar morphology with a large porosity and a high specific surface area but also has an efficient light utilization and carriers‐separation and transfer. Moreover, the calculated optimal Gibbs free energy of adsorbed hydrogen (ΔGH*) for S‐g‐C3N4‐D at the S active sites is close to zero (≈0.24 eV) on the basis of first‐principle density functional theory (DFT). Accordingly, the developed S‐g‐C3N4‐D catalyst shows a high H2 evolution rate of 5651.5 µmol g−1 h−1. Both DFT calculations and experimental results reveal that a memorable defective g‐C3N4/S‐doped g‐C3N4 step‐scheme heterojunction is constructed between S‐doped domains and N‐defective domains in the structural configuration of S‐g‐C3N4‐D. This work exhibits a significant guidance for the design and fabrication of high‐efficiency photocatalysts.

Section: Introductionmentioning

confidence: 99%

Tailoring Advanced N‐Defective and S‐Doped g‐C₃N₄ for Photocatalytic H₂ Evolution

Wang

Jiang

et al. 2023

“…The DOS of AFO/GCN is mainly contributed by AFO (Figure 1f), which is beneficial for enhancing the light absorption of the composite in the visible region. [38] Figure 1g shows the differential charge density diagram of the AFO/GCN heterojunction, with the yellow and blue region representing electron accumulation and depletion, respectively. Evidently, charge redistribution occurs between AFO and GCN, resulting in electrons transferring from GCN to AFO, and eventually concentrating on the AFO side.…”

Section: Theoretical Prediction Of the Formation Of Interface Electri...mentioning

confidence: 99%

“…This may be due to the fact that the GGA function underestimates the bandgap in DFT calculations. [38] The VB energy of GCN and AFO measured by VB-XPS is 1.24 and 2.39 eV, respectively, and their VB values versus normal hydrogen electrode (NHE) can be determined to be 1.3 and 2.45 eV, respectively. [45] Therefore, the CB values of GCN and AFO can be calculated to be −1.23 and −0.43 eV, respectively, according to the relationships between E g , VB, and CB.…”

Section: Analysis Of Band Structure and Charge Transfer Mechanismmentioning

confidence: 99%

Guiding the Driving Factors on Plasma Super‐Photothermal S‐Scheme Core‐Shell Nanoreactor to Enhance Photothermal Catalytic H₂ Evolution and Selective CO₂ Reduction

Xiao,

Wang,

Yao

et al. 2023

Light‐induced heat has a non‐negligible role in photocatalytic reactions. However, it is still challenging to design highly efficient catalysts that can make use of light and thermal energy synergistically. Herein, the study proposes a plasma super‐photothermal S‐scheme heterojunction core‐shell nanoreactor based on manipulation of the driving factors, which consists of α‐Fe2O3 encapsulated by g‐C3N4 modified with gold quantum dots. α‐Fe2O3 can promote carrier spatial separation while also acting as a thermal core to radiate heat to the shell, while Au quantum dots transfer energetic electrons and heat to g‐C3N4 via surface plasmon resonance. Consequently, the catalytic activity of Au/α‐Fe2O3@g‐C3N4 is significantly improved by internal and external double hot spots, and it shows an H2 evolution rate of 5762.35 µmol h−1 g−1, and the selectivity of CO2 conversion to CH4 is 91.2%. This work provides an effective strategy to design new plasma photothermal catalysts for the solar‐to‐fuel transition.

“…[ 2 ] In particular, the elaborately embellished metal ions/clusters in secondary building units (SBUs) of MOFs have recently been shown to achieve inert CH bonds activation and transformation through simultaneously integrating the ligand‐to‐metal charge transfer (LMCT) and hydrogen atom transfer (HAT) events together into metal–organic frameworks. [ 3 ] In the meantime, the past decade has witnessed remarkable advances in vibrant 2D layered nanosized catalytic materials possessing ultrathin thickness research area because of their high surface areas and abundant readily accessible active sites, [ 4 ] such as metal oxides and hydroxides, [ 5 ] boron/carbon nitride, [ 6 ] graphene and graphene oxide, [ 7 ] and transition metal dichalcogenides, [ 8 ] which enhance the communications between the catalytic active sites and substrate molecules and minimize the pathways associated with mass/charge transfer. [ 4,9 ]…”

Section: Introductionmentioning

confidence: 99%

Ultrathin 2D Cerium‐Based Metal–Organic Framework Nanosheet That Boosts Selective Oxidation of Inert C(sp³)H Bond through Multiphoton Excitation

Zhao

Tang

et al. 2023

With the inert and nonpolarized nature, the direct activation and oxidation of inert CH bonds into value-added products under mild conditions is still a more profound challenge when one also targets the desirable outcome of sustainability. [1] Of the reported nanosized catalytic materials, metal-organic frameworks (MOFs) have become an ideal scaffold in catalytic various organic reactions, because of their inherent regular The development of methodologies for inducing and tailoring activities of catalysts is an important issue in various catalysis. The ultrathin 2D monolayer metal-organic framework (MOF) nanosheets with more accessible active sites and faster diffusion obtained by exfoliating 3D layered MOFs are of great potential as heterogeneous catalysts, but the rational design and preparation of 3D layered MOFs remains a grand challenge. Herein, a novel weak electrostatic interaction strategy to construct a 3D layered cerium-bearing MOF by coordinating chlorine-capped cerium nodes and linear photoactive methyl viologen (MV + ) organic linkers is used. Under multiphoton excitation, the MV + ligands and CeCl chromophores are triggered consecutively to form the high activity chlorine radical (Cl • ) for activation of inert C(sp 3 )H bond through a hydrogen atom transfer. Benefiting from framework confinement effects, synergistic effects of two active sites and/or flexibility of the ultrathin framework nanosheets with high surface utilization, the observed activities increase in the order CeCl 3 /MV + < bulk 3D MOF crystals < 2D MOF nanosheets in photocatalysis. This work not only contributes a new strategy to construct 3D layered MOFs and their ultrathin nanosheets but also paves the way to use nanostructured MOFs to handle synergy of multiple molecular catalysts.