Intramolecular π-conjugated channel expansion achieved by doping cross-linked dopants into carbon nitride frameworks for propelling photocatalytic hydrogen evolution and mechanism insight

Abstract

Developing the modified carbon nitride (CN) with multi-bonding mode remains a pivotal challenge for the high-efficiency photocatalytic hydrogen evolution (PHE). Here, we fabricate a PYM-CN photocatalyst by doping pyrimethamine (PYM)...

Finding the Sweet Spot of Photocatalysis─A Case Study Using Bipyridine-Based CTFs

“…Upon illumination, the photo excited CTFs are reductively quenched by reaction with TEOA to yield the reduced CTF radical anion, highlighted by a sharp signal in the EPR spectrum at 337 mT (g ≈ 1.995 -1.999) characteristic for unpaired electrons on aromatic rings with most likely odd numbers of carbon atoms. 46,[48][49][50] The EPR signal intensity increases in the same order as the Urbach tail, showing the strongest signal intensity for CTF-02-Bpy (Figure S18). As expected, bipyridine not only brings additional electrons into the system, but also acts as a donor moiety to the triazine acceptor function, resulting in the observed increase in signal intensity and thus available unpaired electrons.…”

Adjusting Surface Oxidized Layer of CoTe on PCN via In Situ N-Doping Strategy to Promote Charge Separation of Z-Scheme Heterojunction for Propelling Photocatalytic CO2 Reduction

“…The issues of energy shortage and environmental pollution are becoming more and more prominent, which seriously hinders the sustainable development of human society. − Especially for intensifying the greenhouse effect, it is imperative to take the required tactics to reduce the negative impact of greenhouse gases such as CO 2 and develop effective methods to utilize them. − Harnessing inexhaustible solar energy to drive the conversion of CO 2 into high-value chemical products is regarded as a highly promising approach to simultaneously address the global energy demand and escalating environmental issues. − However, the key to this approach lies in the exploitation of photocatalysts that achieve efficient catalytic ability in the CO 2 reduction (CO 2 R) reaction.…”

Facile regeneration of oxidized porous carbon nitride rods by the de-aromatization of the heptazine network in bulk g-C3N4

“…21 In this regard, various strategies have been carried out to engineer the chemical composition and structure of g-C 3 N 4 including heteroatom doping, structural modification, nanocasting, supramolecular assembly, crystallinity engineering, and heterojunction construction. [22][23][24][25][26] Amongst these approaches, nanostructuring (such as designing electrondonor-acceptor conjugated polybenzothiadiazoles, 27 oxalic acid-mediated molecular assembly strategy, 28 and supramolecular assembly of L-arginine with melamine 29 ) is considered as an effective protocol to tailor the morphology, and the resultant electronic and optical properties of g-C 3 N 4 , thus promoting the photoactivity of carbon nitrides. [30][31][32] One-dimensional (1D) rods have been demonstrated to effectively increase the number of active sites and facilitate the electron-hole separation in orthogonal spatial directions, which both could contribute to the enhancement of the photocatalytic performance of g-C 3 N 4 .…”