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

Abstract

Ac rystalline coordination polymer (CP) photocatalyst (Cu-RSH) whichc ombines redox-active copper centers with photoactive rhodamine-derived ligands remains stable in acid and basic solutions from pH 2t o1 4, and efficiently catalyzes dihydrogen evolution at am aximum rate of 7.88 mmol g À1 h À1 in the absence of am ediator and ac ocatalyst. Cyclic voltammetry,c ontrol experiments,a nd DFT calculations established that copper nodes with open coordination sites and favorable redoxp otentials,a ided by spatially ordered stacking of rhodamine-based linkers,a ccount 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.Sunlight-drivensplittingofwater into hydrogen is one of the most promising scenarios for sustainable energy consumption. Thedevelopment of highly efficient, inexpensive noblemetal-free photocatalysts is ap rerequisite,b ut faces many difficult challenges.C oordination polymers (CPs) that combine functional organic ligands with metal centers/clusters (secondary building units,S BUs) have become promising candidates for photoharvesting and the photocatalytic splitting of water. [1][2][3][4] Thes o-far reported CPs for the hydrogen evolution reaction (HER) rely primarily on alimited number of inert Zr-, Al-, Ti-, and Cr-based SBUsa saresult of their stability under harsh catalytic conditions.[2] Moreover,t hey primarily act as supports to host known catalysts that participate in the catalytic reaction, with noble metal Pt particles representing the majority of these catalysts. [2, 3] Developing completely Pt-free and stable CP photocatalysts using redox-active metals,s uch as Fe,C o, Ni, and Cu in combination with photoactive organic ligands would present viable alternatives for transforming sunlight into chemical energy. [1,4]

Directed self-assembly of viologen-based 2D semiconductors with intrinsic UV–SWIR photoresponse after photo/thermo activation

“…The crystals were filtered, washed with water and ethanol, and finally dried in air for 1 day. Yield based on K 3 [Fe(CN) 6 ]: 25% for 2. All crystal samples for tests were carefully selected under microscope.…”

“…P hotoresponse range is a metric that significantly affects the potentials of semiconductors for photodetection, solar energy conversion and other applications [1][2][3][4] . As for photodetection, detection ranges of commercial Si-based photodetectors and InGaAs photodetectors are mostly in the 200-1100 nm and 900-3000 nm regions, respectively 1,5 .…”

Autocatalytic photoredox Chan-Lam coupling of free diaryl sulfoximines with arylboronic acids

“…As hydrogen radicals and copper hydrides have been proposed in copper-catalyzed hydrogen evolution reactions [41][42][43][44][45] , we hypothesized that the byproduct of our reaction might be dihydrogen. Examination of the reaction headspace by gas chromatography (GC) confirmed the formation of hydrogen gas ( Supplementary Fig.…”

Advanced photocatalysts based on metal nanoparticle/metal-organic framework composites

“…As a very promising way to produce clean and sustainable energy, hydrogen production from photocatalytic water splitting attracted extensive research interests in past decades. MOFs, especially incorporated with visible-light chromophores (e.g., amino-substituted terephthalate [94,95], porphyrin [96][97][98][99] or organometallic complex [100][101][102]), have been widely used as heterogeneous photocatalysts for hydrogen production by taking advantage of their semiconductor-like band structure and highly exposed active site. In a typical photocatalytic process, chromophores among MOFs absorb light to generate electron-hole excitons.…”