In situ construction of hydrazone-linked COF-based core–shell hetero-frameworks for enhanced photocatalytic hydrogen evolution

Abstract

Octahedral MOF@COF core–shell hetero-framework photocatalysts were designed which achieved superior photocatalytic H2-evolution activity.

On-Surface Bottom-Up Construction of COF Nanoshells towards Photocatalytic H 2 Production

“…This pore size of 1.8 nm, in good accordance with the data calculated from the XRD peak at 4.7° of CdS@TPPA2 ( Figure 2(a) ), is large enough to accommodate the transfer and diffusion of water, proton, and hydrogen [ 28 – 31 ]. In brief, the core-shell CdS@TPPA nanospheres possess a large specific surface area and well-defined micropore structure, thereby conferring rich active sites for the reaction process, along with abundant channels for the molecule diffusion process [ 32 , 33 ].…”

Metal–Organic Framework‐Based Hybrid Frameworks

“…Furthermore, Chen et al synthesized MOF@COF (NH 2 ‐UiO‐66@TFPT–DETH) core–shell hetero‐frameworks with controllable thicknesses of COF shells for photocatalytic hydrogen evolution under visible light irradiation. [ 136 ] As shown in Figure 10b,c, the designed NH 2 ‐UiO‐66@TFPT‐DETH core–shell heterostructure exhibited superior hydrogen evolution rate of 7178 μmol g −1 h −1 , which was ≈3 times of the original TFPT‐DETH and ≈7 times of their physical hybrid counterpart. In addition, as the thickness of the TFPT–DETH shell increases, the photocatalytic activity of NH 2 ‐UiO‐66@TFPT–DETH samples first rose and then dropped, implying that there may be a balance between the resistance from lengthened transport pathway and the separation of photocarriers in the heterostructure (Figure 10d).…”

Heterostructured MOFs photocatalysts for water splitting to produce hydrogen

“…The heterostructure constructed by two porous materials MOFs and COFs is expected to improve charge separation efficiency while reserving the high porosity beneficial to increase the catalytic sites [80]. There are mainly two typical assembled modes in the construction of MOFs/COFs heterostructure, namely the ''one-pot" process for bulk mixed [81][82][83] and the ''two steps" process for epitaxial growth core-shell structure [84].…”

“…Jiang's group constructed a MOFs@COFs core-shell heterostructure via in situ schiff base polymerization of COFs monomers (TFPT and DETH) on the surface of NH 2 -UiO-66 (Fig. 15) [84]. The formation of imine bonds between NH 2 -UiO-66 and the aldehyde monomer (TFPT) in COF marked the successful synthesis of this heterostructure.…”