This work reports on the use of protein engineering as a versatile tool to rationally design metal-binding proteins for the synthesis of highly photoluminescent protein-stabilized gold nanoclusters (Prot-AuNCs). The use of a single repeat protein scaffold allowed the incorporation of a set of designed metal-binding sites to understand the effect of the metal-coordinating residues and the protein environment on the photoluminescent (PL) properties of gold nanoclusters (AuNCs). The resulting Prot-AuNCs, synthesized by two sustainable procedures, showed size-tunable color emission and outstanding PL properties. In a second stage, tryptophan (Trp) residues were introduced at specific positions to provide an electron-rich protein environment and favor energy transfer from Trps to AuNCs. This modification resulted in improved PL properties relevant for future applications in sensing, biological labeling, catalysis, and optics.

Transparent polymeric matrices serve as efficient platforms to immobilize Tb(BTC) crystals whose fluorescence is quenched in the presence of NO2.

Luminescent metal–organic frameworks (LMOFs) are promising materials for lighting and sensing applications. Herein, exposure of the highly luminescent Zn2(bpdc)2(bpee) MOF (H2bpdc = 4,4′-biphenyldicarboxylic acid and bpee = 1,2-bipyridylethene) to subppm amine contents turns on a new absorption band unambiguously ascribed to free bpee molecules concomitant with the gradual appearance of a new photoluminescence band at shorter wavelengths. These findings combined with Fourier-transform infrared spectra, powder X-ray diffraction and thermogravimetric analysis of exposed LMOF powders confirm that bpee ligands are exchanged by amines and released inside the LMOF, triggering absorption and luminescence features which can be exploited for highly sensitive amine recognition. This principle was demonstrated in mixed matrix membranes (MMMs) prepared by a simple solvent-free method consisting of mixing Zn2(bpdc)2(bpee) with dimethylvinyl-terminated dimethylsiloxane and dimethylhydrogen siloxane. This method enabled the production of free-standing, permeable, and highly transparent MMMs which showed enormous potential and sensitivity to the detection of amines in gas phase and aqueous medium.

A selective luminescent sensor was fabricated by simply mixing a Tb(iii)-based MOF with polymethylmetahacrylate enabling to detect sub-ppb range of nitroaromatic vapours.

We report on the theoretical and experimental studies of the new dye-sensitized solar cells functionalized with 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin zinc(II) complexes bearing 2- and 8-bromo substituents at the β positions. In agreement with the results of TD-DFT calculations, the absorption maxima of di- and octa-brominated Zn(II) complexes, ZnTCPPBr2 and ZnTCPPBr8, exhibited large red-shift compared to that of the non-brominated free base porphyrin (H2TCPP). Furthermore, DFT calculations showed that the higher stabilization of the LUMO levels relative to the HOMO ones makes the HOMO-LUMO gap of the brominated Zn-porphyrins models smaller compared to that of the nonbrominated counterparts, which explains the red shifts of the Soret and Q bands of the brominated compounds. Solar cells containing the new saddle-shaped Zn(II) porphyrins were subjected to analysis in a photovoltaic calibration laboratory to determine their solar to electric energy conversion. In this regard, we found that the overall conversion efficiency of ZnTCPPBr8 adsorbed on TiO2 nanocrystalline films was 5 times as large as that of ZnTCPPBr2 adsorbed on the same films. The effect of the increasing number of Br groups on the photovoltaic performance of the complexes was compared to the results of computational methods using ab initio DFT molecular dynamics simulations and quantum dynamics calculations of electronic relaxation to investigate the interfacial electron transfer (IET) in TCPPBrx/TiO2-anatase nanostructures. Better IET in ZnTCPPBr8 compared to ZnTCPPBr2, and in H2TCPP was evaluated from interfacial electron transfer (IET) simulations. The IET results indicate that electron injection in ZnTCPPBr8-TiO2 (τ = 25 fs) can be up to 5 orders of magnitude faster than ZnTCPPBr2-TiO2 (τ = 125 fs). Both experimental and theoretical results demonstrate that the increase of the number of bromo-substituents at the β-pyrrole positions of the porphyrin macrocycle created a new class of porphyrin-based DSSC, which exhibits a remarkable increase in the photovoltaic performance compared to non-brominated porphyrins.

A simple approach for the fabrication of functional nanopatterned protein materials using protein engineering and soft-nanolithography and its implementation in optical devices based on distributed feedback (DFB) laser phenomena.

Here we present the assembly of novel transparent all-polymer distributed feedback (DFB) lasers. Flexible and highly transparent cellulose diacetate (CdA) was employed as substrate on which gratings with different periods were engraved by thermal nanoimprinting with high fidelity. Highly luminescent conjugated polymers (CP), poly (9,9-dioctylfluorene) (PFO), poly(9,9dioctylfluorene-alt-benzothiadiazole) (F8BT), and a blend of F8BT and poly(3-hexylthiophene)-poly(9,9-dioctylfluorene-altbenzothiadiazole) (P3HT:F8BT) were deposited by spin coating onto the nanostructured plastic surfaces, giving rise to perpendicular single-mode lasing emission in the blue, green, and red wavelength ranges, respectively. These lasers show linewidths below 1 nm and low thresholds (≈6 μJcm −2 for blue and red lasing emission), comparable to other state-of-the-art lasers obtained from similar optical gain materials on rigid substrates. The followed strategy is scalable and versatile, enabling the development of large area nanoimprinted DFB lasers (>1cm 2 ) on plastic, which is highly relevant for applications in various markets.npj Flexible Electronics (2019) 3:17 ; https://doi.

State‐of‐the‐art near‐infrared lasers based on poly[N‐9′‐heptadecanyl‐2,7‐carbazole‐alt‐5,5‐(4′,7′‐di‐2‐thienyl‐2′,1′,3′‐benzothiadiazole)] (PCDTBT) and poly(9,9‐dioctylfluorene‐alt‐benzothiadiazole) (F8BT) blends are reported. Polymer light‐emitting diodes (PLEDs) based on PCDTBT/F8BT blends with 30 wt% PCDTBT content exhibit a maximum radiance of 64.3 W sr−1 m−2 and external quantum efficiency of 2.11% with Commission Internationale de L'Eclairage (CIE) coordinates (x = 0.69, y = 0.30). Using an optimal blend ratio of 15 wt% PCDTBT in F8BT, a maximum gain value of 28.2 cm−1 at 710 nm is achieved, a remarkable value given that PCDTBT is a low emissive polymer extensively employed as donor polymer in organic photovoltaics. The lowest amplified spontaneous emission (ASE) and laser thresholds exhibited by the blends are 590 nJ pulse−1 (21 µJ cm−2) and 63.1 nJ pulse−1 (201 µJ cm−2). Transient absorption spectroscopy confirms efficient Förster resonant energy transfer from F8BT to PCDTBT which, together with the large miscibility of PCDTBT in F8BT, enables PCDTBT emission enhancement and optical gain. Furthermore, a ternary blend system composed of F8BT, PCDTBT, and poly(3‐hexylthiophene) is demonstrated, in which the ASE wavelength can be tuned in a 60 nm range from 650 to 710 nm at a very low threshold level via control of the blend content ratio.