Given that energy (exciton) migration in natural photosynthesis primarily occurs highly ordered porphyrin-like pigments (chlorophylls), equally porphyrin-based metal-organic frameworks (MOFs) might be expected to exhibit similar behavior, thereby facilitating antenna-like light-harvesting and positioning such materials for use solar conversion schemes. Herein, we report the first example of directional, long-distance within a MOF. Two MOFs, namely F-MOF DA-MOF are composed two Zn(II)...

Because of their efficient energy-transport properties, porphyrin-based metal-organic frameworks (MOFs) are attractive compounds for solar photochemistry applications. However, absorption bands provide limited coverage in the visible spectral range light-harvesting We report here functionalization MOFs with CdSe/ZnS core/shell quantum dots (QDs) enhancement light harvesting via energy transfer from QDs to MOFs. The broad band region offers greater spectrum by QD-MOF hybrid structures. show...

We report the synthesis and characterization of two thin films (DA-MOF L2-MOF) porphyrin-based MOFs on functionalized surfaces using a layer-by-layer (LbL) approach. Profilometry measurements confirm that film thickness increases systematically with number growth cycles. Polarization excitation fluorescence indicate porphyrin units are preferentially oriented, while X-ray reflectivity scans point to periodic ordering. Ellipsometry show highly porous. Since there currently few methods capable...

Herein we report a detailed investigation of highly robust hybrid system (sensitizer/TiO2/catalyst) for the visible-light reduction CO2 to CO; comprises 5′-(4-[bis(4-methoxymethylphenyl)amino]phenyl-2,2′-dithiophen-5-yl)cyanoacrylic acid as sensitizer and (4,4′-bis(methylphosphonic acid)-2,2′-bipyridine)ReI(CO)3Cl catalyst, both which have been anchored on three different types TiO2 particles (s-TiO2, h-TiO2, d-TiO2). It was found that remarkable enhancements in conversion activity...

Abstract Visible‐light irradiation of a ternary hybrid catalyst prepared by grafting dye, an H 2 evolving Co III and CO‐producing Re I on TiO have been found to produce both CO (syngas) in ‐saturated N , ‐dimethyl formamide (DMF)/water solution containing 0.1 m sacrificial electron donor. The /CO ratios are effectively controlled changing either the water content solvent or molar ratio catalysts ranging from 1:2 15:1. syngas formation is discussed terms competitive flow each ‐reduction...

A series of Zn–porphyrin dyes was prepared and anchored onto a TiO2 surface to complete dye-sensitized photocatalyst system, Zn–porphyrin-|TiO2|-Cat, tested as lower energy photosensitizers for photocatalytic CO2 reduction. Three major synthetic modifications were performed on the dye obtain sensitization improve catalyst lifetime. We found that incorporating acetylene linear hexyl groups into core allowed facile sensitization, addition cyanophosphonic acid an anchoring group gave long-term...

ConspectusDuring the last few decades, design of catalytic systems for CO2 reduction has been extensively researched and generally involves (1) traditional approaches using molecular organic/organometallic materials heterogeneous inorganic semiconductors (2) combinatory wherein these are combined as needed. Recently, we have devised a number new TiO2-mediated multicomponent hybrid that synergistically integrate intrinsic merits various materials, namely, photosensitizers/catalysts n-type...

A porphyrinic metal–organic framework (PMOF) known as PCN-222(Zn) was chemically doped with a molecular Re(I) catalyst-bearing carboxylate anchoring group to form new type of (MOF)–Re(I) hybrid photocatalyst. The MOF-sensitized (PMOF/Re) prepared an archetypical CO2 reduction catalyst, (L)ReI(CO)3Cl (Re(I); L = 4,4′-dicarboxylic-2,2′-bipyridine), in the presence 3 vol % water produced CO no leveling-off tendency for 59 h give turnover number ≥1893 [1070 ± 80 μmol h–1 (g MOF)−1]. high...

A major loss mechanism in dye-sensitized solar cells (DSCs) is recombination at the TiO(2)/electrolyte interface. Here we report a method to reduce greatly this mechanism. We deposit insulating and transparent silica (SiO(2)) onto open areas of nanoparticulate TiO(2) surface while avoiding any deposition SiO(2) over or under organic dye molecules. The coating covers highly convoluted conformally with uniform thickness throughout thousands layers nanoparticles. DSCs incorporating these...

Detachment (desorption) of molecular dyes from photoelectrodes is one the major limitations for long-term operation dye-sensitized solar cells. Here we demonstrate a method to greatly inhibit this loss by growing transparent metal oxide (TiO2) on dye-coated photoelectrode via atomic layer deposition (ALD). TiO2-enshrouded sensitizers largely resist detachment, even in pH 10.7 ethanol, standard solution intentional removal photoelectrodes. Additionally, ALD post-treatment renders otherwise...

Electron donor-acceptor (D-A) systems with a triphenylamino moiety (D) and ortho-carborane (A) show three kinds of intriguing emissions that can be attributed to the local excited state, intramolecular charge-transfer aggregation-induced emission state. The behaviors depend on which positions carborane are substituted.

Carborane-based donor-π-acceptor triads (D-π-A-π-D) bearing triarylamine moieties were synthesised. All the monomeric showed a blue-green emission in dilute solution, which was assigned as an intramolecular charge-transfer (CT) emission. The CT large Stokes shifts at higher solvent polarity. further shifted to longer wavelength with increase π-conjugation. Interestingly, strong red observed highly concentrated solutions or solid state, aggregation-induced (AIE). Moreover, AIE strongly...

A Mn(I)-based hybrid system (OrgD-|TiO2|-MnP) for photocatalytic CO2 reduction is designed to be a coassembly of Mn(4,4′-Y2-bpy)(CO)3Br (MnP; Y = CH2PO(OH)2) and (E)-3-[5-(4-(diphenylamino)phenyl)-2,2′-bithiophen-2′-yl]-2-cyanoacrylic acid (OrgD) on TiO2 semiconductor particles. The OrgD-|TiO2|-MnP reveals persistent behavior, giving high turnover numbers good product selectivity (HCOO– versus CO). As typical run, visible-light irradiation the catalyst in presence 0.1 M electron donor (ED)...

Quantum dots (QDs) have emerged as an important class of materials for diverse applications such solid-state lighting, energy conversion, displays, biomedicine, and plasmonics due to their excellent photonic properties durability. Soft lithography, inkjet printing, nanoimprinting, polymer deep-pen lithography are primary techniques employed implement micro-patterns with QDs, however, there limited reports on QD photolithography using conventional processes suitable mass production. This...

Color-tunable Zn(II) complexes of the type Zn( N,O-OPh (OxZ)ArX) 2 ( 5), where ligand consists an oxazolylphenolate ion connected at 4-position by a 2,4-substituted aryl functional group with X = NMe a, OMe b, Ph c, Cl d, F e, and CN f, were prepared. X-ray structural studies 5a, 5b, 5e showed that zinc atom was positioned in distorted tetrahedral coordination environment created two ligands N,O-chelation. Hammet plots absorption emission maxima, respectively, UV photoluminescence (PL)...

The influence of π-conjugation structural changes on photoinduced electron transfer (PET) and intramolecular charge (ICT) processes in π-conjugated donor (D)-acceptor (A) dyads (D-π-A) was investigated. Three types D-π-A were prepared through the modification structure their linker, including (1) D-πtw-A (2) having a twisted π-conjugation, D-π-Si-π-A (3) with severed by Si-atom. In these dyads, carbazole (Cz) oxadiazole (Oz) moieties act as an acceptor, respectively. emission maxima 1 3...

A series of cationic Ir(III) complexes ([Ir(btp)2(bpy-X2)]+ (Ir-X+: btp = (2-pyridyl)benzo[b]thiophen-3-yl; bpy-X2 4,4'-X2-2,2'-bipyridine (X OMe, tBu, Me, H, and CN)) were applied as visible-light photosensitizer to the CO2 reduction CO using a hybrid catalyst (TiO2/ReP) prepared by anchoring Re(4,4'-Y2-bpy)(CO)3Cl (ReP; Y CH2PO(OH)2) on TiO2 particles. Irradiation solution containing Ir-X+, TiO2/ReP particles, an electron donor (1,3-dimethyl-2-phenyl-1,3-dihydrobenzimidazole) in...

In this study, an InP-cored quantum dot (InP-QD) material was prepared and physically immobilized on TiO2 particles functionalized with archetypical reduction catalyst, (4,4-Y2-bpy)ReI(CO)3Cl (ReP, Y = CH2PO(OH)2), to form a new type of InP dot-sensitized hybrid photocatalyst (InP-QD/TiO2/ReP) evaluated as lower-energy photosensitizer in system. It found that the heterogenization InP-QD promotes photoexcited electron transfer process from InP-QD* inorganic solid rapid injection (by ∼25 ps)...

Panchromatic 1,6-bis(N-phenyl-p-(R)-phenylamino)pyrenes, 2R, were obtained from Buchwald-Hartwig coupling reactions between N-phenyl-p-(R)-phenylamines and 1,6-dibromopyrene. The photophysical properties of 2R corresponded well to the electron-withdrawing -donating nature diarylamine substituents, exhibiting a full color visible range 454 620 nm. In particular, deep blue 2CN showed high radiative rate constant 2.85 x 10(8) s(-1) with emission quantum efficiency 79%. Further applications as...

A series of dyes were synthesized to examine the roles hydrophilic characteristics R in sensitized hydrogen generation by dye-grafted Pt/TiO(2) under visible light irradiation. The hydrogen-generation efficiencies and optimum amounts grafted affected substantially steric effects R; moderately DEO1 DEO2 showed higher sensitization activity at a lower loading than hydrophobic D-H.

Wide-band-gap phosphorescent organic light-emitting diode (OLED) host materials were developed employing the tetrahedral structural motif of silicon atom, which functioned further to connect 4-(N-carbazolyl)phenyl (CP) units in its periphery (2a−2d). The thermal, photophysical, and electrochemical properties, X-ray studies as well OLED device characteristics fully investigated. Silicon effectively disconnected charge delocalization between CP units. By low temperature PL study, triplet...

Improvement of the stability blue phosphorescent dopant material is one key factors for real application organic light-emitting diodes (OLEDs). In this study, we found that intramolecular hydrogen bonding in an ancillary ligand from a heteroleptic Ir(III) complex can play important role phosphorescence. To rationalize bonding, series complexes designed and prepared: Ir(dfppy)2(pic-OH) (1a), Ir(dfppy)2(pic-OMe) (1b), Ir(ppy)2(pic-OH) (2a), Ir(ppy)2(pic-OMe) (2b). The emission lifetime (1a)...

Dye aggregation and concomitant reduction of dye excited-state lifetimes electron-injection yields constitute a significant mechanism for diminution light-to-electrical energy conversion efficiencies in many dye-sensitized solar cells (DSCs). For TiO2-based DSCs prepared with an archetypal donor–acceptor organic dye, (E)-2-cyano-3-(5′-(5′′-(p-(diphenylamino)phenyl)-thiophen-2′′-yl)thiophen-2′-yl)acrylic acid (OrgD), we find, part via ultrafast spectroscopy measurements, that...

To gain new insights into ligand-to-ligand charge-transfer (LLCT) dynamics, we synthesised two heteroleptic Ir(3+) complexes: (Ir(dfppy)2(tpphz)) and (Ir(dfppy)2(dpq)), where dfppy, tpphz, dpq are 2-(4,6-difluorophenyl)pyridine, tetrapyrido[3,2-a:2',3'-c:3'',2''-h:2''',3'''-j]phenazine, 2,3-bis-(2-pyridyl)-quinoxaline, respectively. The tpphz ligands have longer π-conjugation than dfppy. Therefore, the excited ligand-centred (LC) state metal-to-ligand charge transfer (MLCT) of dfppy higher...

Dye-sensitized solar cells, especially those comprising molecular chromophores and inorganic titania, have shown promise as an alternative to silicon for photovoltaic light-to-electrical energy conversion. Co-sensitization (the use of two or more having complementary absorption spectra) has attracted attention a method harvesting photons over broad spectral range. If implemented successfully, then cosensitization can substantially enhance photocurrent densities conversion efficiencies. In...