Boosting photocatalytic hydrogen evolution of covalent organic frameworks by introducing 2D conductive metal–organic frameworks as noble metal-free co-catalysts

Abstract

Covalent organic frameworks (COFs) as new photocatalysts for hydrogen evolution have aroused considerable interest over the past years. However, most of COF-based photocatalysts require expensive and rare Pt co-catalyst to...

Construction of Benzodithiophene-Based Donor–Acceptor-Type Covalent Triazine Frameworks with Tunable Structure for Photocatalytic Hydrogen Evolution

“…After pre-irradiation for 1 hour to deposit the Pt completely on the CTFs, the reaction mixture was exposed under visible light for another 2 hours to obtain the average activity data for BDT-CTF-1, BDT-CTF-2, and BDT-CTF-3, which was 4500, 2170, and 1160 μmol h –1 g –1 , respectively (Figure a). The apparent quantum yield (AQY) tests were further carried out with a band-pass filter (420 ± 5 nm), and the results for samples 1–3 were confirmed to be 3.9, 3.7, and 1.1%, relatively close to those for the previously reported conjugated organic porous polymer HER systems. − On the other hand, in this system, the HER rate of BDT-CTF-1 was about twofold that of BDT-CTF-2 and 4 times that of BDT-CTF-3, and the photocatalytic efficiency decreased as the BDT monomers in the CTFs increased. The hydrogen was confirmed to be photocatalytically produced with the presence of BDT-CTFs by control experiments wherein all catalytic systems were kept in dark or irradiated without photocatalysts.…”

Recent advances in the synthesis and catalytic applications of metal–organic framework/covalent organic framework composites

“…Even though the MOFs and COFs can be prepared respectively and then combined by vigorous grinding, their poor contact limits their synergistic effects. 83 Recently, a novel NH 2 -MIL-125(Ti)/B-CTF-1(TBC) using synthetic covalent modification techniques was successfully prepared by the amide bond. 19 CTF-1 was modified by a benzoic acid fragment to form B-CTF-1, which was then covalently-linked with NH 2 -MIL-125(Ti) or NH 2 -UiO-66(Zr) by chemically covalent amide bonds (Fig.…”

“…Similarly, Tang et al prepared Tp-Pa-2/Cu 3 (HHTP) 2 via an easy handling and green mechanochemical method, and the obtained Tp-Pa-2/Cu 3 (HHTP) 2 composite photocatalyst with a mass ratio of 3 : 1 showed the highest photocatalytic H 2 evolution rate of 7.71 mmol h À1 g À1 as well as good cycling stability under visible light irradiation. 83 Covalent linkages are often created to connect MOF and COF in the field of photocatalytic H 2 evolution to facilitate the separation of photoinduced charge carriers. Even though imine bonds are the most investigated, some other types have also been reported.…”

Covalent Organic Frameworks Based Heterostructure in Solar‐To‐Fuel Conversion

“…The COFs include TpPA, [ 35–39 ] LZU, [ 40 ] CTF, [ 41 ] TD, [ 42 ] TpBD, [ 43 ] and 318 [ 17,44 ] et al. And the combined materials include TiO 2 , [ 17,45–47 ] CdS, [ 35,48–53 ] C 3 N 4 , [ 43,54–58 ] and metal–organic frameworks [ 37,39,41,59–63 ] et al. (For ease of discussion, the sum of these materials is sometimes been referred to as the support in this manuscript).…”

“…[35] Since then, there has been a surge of research in this field. The COFs include TpPA, [35][36][37][38][39] LZU, [40] CTF, [41] TD, [42] TpBD, [43] and 318 [17,44] et al And the combined materials include TiO 2 , [17,[45][46][47] CdS, [35,[48][49][50][51][52][53] C 3 N 4 , [43,[54][55][56][57][58] and metal-organic frameworks [37,39,41,[59][60][61][62][63] et al (For ease of discussion, the sum of these materials is sometimes been referred to as the support in this manuscript). These heterostructures show outstanding performances in photocatalytic fuel production processes, e.g., hydrogen evolution reaction (HER), carbon dioxide reduction reaction (CDRR), H 2 O splitting together with CO 2 splitting.…”