A Crystalline Copper(II) Coordination Polymer for the Efficient Visible‐Light‐Driven Generation of Hydrogen

Abstract

A crystalline coordination polymer (CP) photocatalyst (Cu-RSH) which combines redox-active copper centers with photoactive rhodamine-derived ligands remains stable in acid and basic solutions from pH 2 to 14, and efficiently catalyzes dihydrogen evolution at a maximum rate of 7.88 mmol g(-1) h(-1) in the absence of a mediator and a co-catalyst. Cyclic voltammetry, control experiments, and DFT calculations established that copper nodes with open coordination sites and favorable redox potentials, aided by spatially ordered stacking of rhodamine-based linkers, account for the high catalytic performance of Cu-RSH. Emission quenching, time-resolved fluorescence decay, and transient photocurrent experiments disclosed the charge separation and transfer process in the catalytic system. The present study demonstrates the potential of crystalline copper CPs for the practical utilization of light.

A Methylthio‐Functionalized‐MOF Photocatalyst with High Performance for Visible‐Light‐Driven H2 Evolution

“…[11] This value also is much higher than for representative photocatalytic MOFs.Itisover 200 %o ft hat of the sensitized Pt/g-C 3 N 4 @UiO-66 (1411 mmol g À1 h À1 ) [19b] and Calix-3/Pt@UiO-66-NH 2 -1-200 (1528 mmol g À1 h À1 ), [19f] being to our knowledge,t he most photoactive MOF-based materials (Figure 3b and Table S3). Forb etter clarifying the photocatalytic performance,t he quantum efficiencies (QE) [17] at 420 nm of Pt/20 %-MIL-125-(SCH 3 ) 2 and Pt/50 %-MIL-125-(SCH 3 ) 2 were calculated to be about 5.99 %and 8.90 %, respectively ( Figure S5). Such QEs even are much higher than that (4.3 %) of the ZnIn 2 S 4 @MIL-125-NH 2 (Table S1).…”

Renewable Molecular Flasks with NADH Models: Combination of Light‐Driven Proton Reduction and Biomimetic Hydrogenation of Benzoxazinones

“…[2,3] An exciting area in this research includes the incorporation of transition-metal moieties as redox-active vertices that mimic the highly evolved and finely tuned natural photocatalytic systems by catching organic dyes in the pocket. [4,5] Such aseparation of the redox events by the inner and outer spaces of the cavity provides an ew synthetic platform that combines photocatalytic reduction with as pecific hydrogenation reaction.Nature has developed millions of redox systems in which the redox process is catalyzed by numerous coenzymes. [6,7] Taking advantage of modified prototypes and hydride reduction cofactors,chemists have developed abiomimetic hydrogenation approach employing Hantzsch esters with relevant compounds that function as mimics of nicotinamide adenine dinucleotide (NADH).…”

“…[2,3] An exciting area in this research includes the incorporation of transition-metal moieties as redox-active vertices that mimic the highly evolved and finely tuned natural photocatalytic systems by catching organic dyes in the pocket. [4,5] Such aseparation of the redox events by the inner and outer spaces of the cavity provides an ew synthetic platform that combines photocatalytic reduction with as pecific hydrogenation reaction.…”

Renewable Molecular Flasks with NADH Models: Combination of Light‐Driven Proton Reduction and Biomimetic Hydrogenation of Benzoxazinones

“…By modulating the active site of an icotinamide adenine dinucleotide (NADH) model in aredox-active molecular flask, we combined biomimetic hydrogenation with in situ regeneration of the active site in aone-pot transformation using light as ac lean energy source.T his molecular flask facilitates the encapsulation of benzoxazinones for biomimetic hydrogenation of the substrates within the inner space of the flask using the active sites of the NADH models.T he redox-active metal centers providea na ctive hydrogen source by light-driven proton reduction outside the pocket, allowing the in situ regeneration of the NADH models under irradiation. [4,5] Such aseparation of the redox events by the inner and outer spaces of the cavity provides an ew synthetic platform that combines photocatalytic reduction with as pecific hydrogenation reaction.Nature has developed millions of redox systems in which the redox process is catalyzed by numerous coenzymes. [1] To match the efficiency and selectivity of enzymatic systems,c hemists use small molecules with defined hydrophobic cavities that emulate the properties of enzyme active sites to catalyze specific chemical transformations.…”

“…[1] To match the efficiency and selectivity of enzymatic systems,c hemists use small molecules with defined hydrophobic cavities that emulate the properties of enzyme active sites to catalyze specific chemical transformations. [4,5] Such aseparation of the redox events by the inner and outer spaces of the cavity provides an ew synthetic platform that combines photocatalytic reduction with as pecific hydrogenation reaction. [4,5] Such aseparation of the redox events by the inner and outer spaces of the cavity provides an ew synthetic platform that combines photocatalytic reduction with as pecific hydrogenation reaction.…”