Substituent group-tunable hydrogen evolution activity observed in isostructural Cu(ii)-based coordination polymer photocatalysts

Abstract

The substituent group effect on the photocatalytic hydrogen evolution activity for water splitting was observed over a series of five isostructural copper(ii)-based layered coordination polymer photocatalysts.

Ligand-Mediated Regulation of the Chemical/Thermal Stability and Catalytic Performance of Isostructural Cobalt(II) Coordination Polymers

“…It is well-known that the substituent groups attached to the ligand backbones might play an important role in governing the network structures of acid–base mixed-ligand CPs. Numerous mixed-ligand CPs, especially those with transition-metal centers, have been synthesized by selecting N-heterocyclic ligands incorporated with a series of comparable R-terephthalic acids or R-isophthalic acids with different substituents. − In our previous work, we employed Fbtx and phthalate as mixed ligands to prepare a stable Cu­(II)-based CP under hydrothermal conditions . To further investigate the ligand effect of CPs, four new Co-CP-R were obtained under both hydrothermal and microwave conditions.…”

Photocatalytic hydrogen evolution activity over Pt-assisted metal-organic frameworks dominated by transition metal ions and local coordination environments

“…By contrast, (3) displays two separate bands with a strong and abroad absorption between 200 and 443 nm and a weak one centered at 504 nm. The absorption in the UV region of (1)−(3) can be respectively resulting from to π→π * and n→π * transitions of the HL ligand, and the latter one in the visible range is resulting from the d-d spin-allowed transition of the octahedral Co II ion [16,17,22]. Furthermore, these absorptions of (1)−(3) are blue-shift as compared with HL ligand originated from the coordination interactions of the metal ion with organic ligand.…”

“…Semiconductive metal-organic frameworks (MOFs) constructed from well-defined organic ligands and earthabundant transition metal nodes/clusters have recently becoming promising candidates of photocatalysts for hydrogen production from water decomposition due to their tunable bandgaps, high surface areas, and tailorable backbone stability [4][5][6][7]. Since the pioneering work of non-precious d-block metal-derived MOF photocatalysts for the photolysis water under visible light irradiation [8,9], lots of MOFs with cheap transition metal ions (Cu I/II , Ni II , and Co II ) and bulky delocalized organic ligands (such as 2-mercaptonicotinic acid, pyrimidine-2-thio, terpyridyl-and porphyrinyl-derivatives) have been fabricated up to date, with the production rates increased greatly from 0.032 to 19.3 mmol • g −1 • h −1 [8][9][10][11][12][13][14][15][16][17]. Apparently, the enhanced catalytic activity over these MOF photocatalysts benefit significantly from the broadened light absorption, suitable bandgaps for electron-hole separation, quickening the charge transport, and favorable absorption of the active species on the substrate through optimizing the substitutes appended on the conjugated organic ligands, varying the types of the metal centers, and well-tailing the porosity nature of the resulting MOFs.…”