Potassium-doped carbon nitride: Highly efficient photoredox catalyst for selective oxygen reduction and arylboronic acid hydroxylation

Triple-Phase Photocatalytic H2O2 Production on a Janus Fiber Membrane with Asymmetric Hydrophobicity

“…X-ray photoelectron spectroscopy (XPS) was employed to further examine the chemical composition and valence state of CN and mCN. The K species in mCN show two peaks at 295.24 eV (K 2p 1/2 ) and 293.03 eV (K 2p 3/2 ; Figure d), close to the binding energy of the K–N species. − This indicates that the incorporated K species are preferentially stabilized by the N sites in mCN, agreeing well with previous reports . This point is further evidenced by the high-resolution N 1s XPS spectra shown in Figure e.…”

“…33−36 This indicates that the incorporated K species are preferentially stabilized by the N sites in mCN, agreeing well with previous reports. 35 This point is further evidenced by the high-resolution N 1s XPS spectra shown in Figure 2e. After incorporating K species in mCN, the binding energy of N in C−N�C motifs shows a shift toward a large value relative to bare CN.…”

“…The K dopant can also enhance the O 2 chemisorption and activation, probably by activating the nearby C and N sites, which is beneficial for the conversion of O 2 to H 2 O 2 . 35,40,41 Therefore, it is expected to enhance the photocatalytic H 2 O 2 production activity of mCN.…”

Dual Defective K-Doping and Cyano Group Sites on Carbon Nitride Nanotubes for Improved Hydrogen Photo-Production

“…In the case of CN materials, nitrogen defects including the cyano group (−CN) have been studied for the improvement of the light absorption spectrum and charge transfer rate. , It is noteworthy that the metal-ion-assisted method can simultaneously induce cyano defects as the proton acceptor and metal-ion dopants as the hole donor in the CN framework. Recently, many metals such as Na + , K + , Co 2+ , and Cu 2+ have been doped to CN exhibiting enhanced overall activities. − Furthermore, metal-ion dopants can establish ion–dipole interactions with nitrogen tanks in CN to optimize the energy band and electronic structures . Recently, K ions implantation into CN induced the generation of cyano groups and constructed a built-in electric field to facilitate the separation of photogenerated electron–hole pairs, thereby it has increased 34 times compared with the pure CN for visible light hydrogen production .…”

Improving the crystallinity of imine-linked covalent organic frameworks by acetal for enhanced photocatalytic H2O2evolution

“…In recent years, organic semiconductors, such as g-C 3 N 4 and covalent organic frameworks (COFs), have drawn great attention because their conjugated building blocks can endow them with electronic delocalization, so that they have an excellent visible-light response and the ability to migrate excitons. [10][11][12][13][14][15][16] COFs are new organic polymeric porous materials with a high surface area assembled by π-conjugated monomers via irreversible or reversible bonds, and have been applied in sensors, 17 storage, 18,19 purification, 20,21 and catalysis. [22][23][24][25][26][27][28][29][30][31] We showed previously that fluorinated imine-linked COF, TFA-TaPt-COF, has a higher structural stability than the unfluorinated one.…”