Valorization and repurposing of seafood waste to next-generation carbon nanofertilizers.

The surge in population growth, urbanization, and shifts in food consumption patterns have resulted in a rise in the global production of organic waste. This waste material must be repurposed and effectively managed to minimize environmental footprints. The generation of abundant biowaste, especially from marine sources, may have detrimental impacts on the environment and human health if left untreated.

Dual Aliovalent Dopants Cu, Mn Engineered Eco-Friendly QDs for Ultra-Stable Anti-Counterfeiting.

Doping in semiconductor quantum dots (QDs) using optically active dopants tailors their optical, electronic, and magnetic properties beyond what is achieved by controlling size, shape, and composition. Herein, we synergistically modulated the optical properties of eco-friendly ZnInSe/ZnSe core/shell QDs by incorporating Cu-doping and Mn-alloying into their core and shell to investigate their use in anti-counterfeiting and information encryption. The engineered "Cu:ZnInSe/Mn:ZnSe" core/shell QDs exhibit an intense bright orange photoluminescence (PL) emission centered at 606 nm, with better color purity than the undoped and individually doped core/shell QDs.

Heavy-Metal-Free Colloidal Quantum Dots: Progress and Opportunities in Solar Technologies.

Colloidal quantum dots (QDs) hold great promise as building blocks in solar technologies owing to their remarkable photostability and adjustable properties through the rationale involving size, atomic composition of core and shell, shapes, and surface states. However, most high-performing QDs in solar conversion contain hazardous metal elements, including Cd and Pb, posing significant environmental risks. Here, a comprehensive review of heavy-metal-free colloidal QDs for solar technologies, including photovoltaic (PV) devices, solar-to-chemical fuel conversion, and luminescent solar concentrators (LSCs), is presented.

Titanium Carbide (TiCT) MXene for Sequestration of Aquatic Pollutants.

The rapid expansion of industrialization has resulted in the release of multiple ecological contaminants in gaseous, liquid, and solid forms, which pose significant environmental risks to many different ecosystems. The efficient and cost-effective removal of these environmental pollutants has attracted global attention. This growing concern has prompted the synthesis and optimization of nanomaterials and their application as potential pollutant removal.

Harnessing the Synergetic Effects of Ag, Mn Dopants in Eco-Friendly Ultraviolet Selective Quantum Dots for Luminescent Solar Concentrators.

Quantum dots (QDs) are promising building blocks for luminescent solar concentrators (LSCs), yet most QD-based LSCs suffer from toxic metal composition and color tinting. UV-selective harvesting QDs can enable visible transparency, but their development is restricted by large reabsorption losses and low photoluminescence quantum yield (PLQY). The developed here Ag, Mn: ZnInS/ZnS QDs show a high PLQY of 53% due to the passivating effect of ZnS shell.

Highly bright solid-state carbon dots for efficient anticounterfeiting.

Carbon dots (C-dots) as promising fluorescent materials have attracted much attention because of their low toxicity and excellent optoelectronic properties. However, the aggregation-caused quenching (ACQ) of the solid-state C-dots has limited their potential applications in anti-counterfeiting and optoelectronic devices. In this work, C-dot powder was prepared by directly dispersing the as-prepared C-dots in a polymer matrix or formation of the C-dot/Ca-complex by vacuum heating in the presence of boric acid.

Advanced Interface Engineering in Gradient Core/Shell Quantum Dots Enables Efficient Photoelectrochemical Hydrogen Evolution.

Semiconductor core/shell quantum dots (QDs) are considered promising building blocks to fabricate photoelectrochemical (PEC) cells for the direct conversion of solar energy into hydrogen (H). However, the lattice mismatch between core and shell in such QDs results in undesirable defects and severe carrier recombination, limiting photo-induced carrier separation/transfer and solar-to-fuel conversion efficiency. Here, an interface engineering approach is explored to minimize the core-shell lattice mismatch in CdS/CdSeS (x = 0.

Surface engineering of two-dimensional hexagonal boron-nitride for optoelectronic devices.

Two-dimensional hexagonal boron nitride (2D h-BN) is being extensively studied in optoelectronic devices due to its electronic and photonic properties. However, the controlled optimization of h-BN's insulating properties is necessary to fully explore its potential in energy conversion and storage devices. In this work, we engineered the surface of h-BN nanoflakes one-step chemical functionalization using a liquid-phase exfoliation approach.

Efficient Photoelectrochemical Hydrogen Generation Using Eco-Friendly "Giant" InP/ZnSe Core/Shell Quantum Dots.

InP quantum dots (QDs) are promising building blocks for use in solar technologies because of their low intrinsic toxicity, narrow bandgap, large absorption coefficient, and low-cost solution synthesis. However, the high surface trap density of InP QDs reduces their energy conversion efficiency and degrades their long-term stability. Encapsulating InP QDs into a wider bandgap shell is desirable to eliminate surface traps and improve optoelectronic properties.

Rational Control of Near-Infrared Colloidal Thick-Shell Eco-Friendly Quantum Dots for Solar Energy Conversion.

Thick-shell colloidal quantum dots (QDs) are promising building blocks for solar technologies due to their size/composition/shape-tunable properties. However, most well-performed thick-shell QDs suffer from frequent use of toxic metal elements including Pb and Cd, and inadequate light absorption in the visible and near-infrared (NIR) region due to the wide bandgap of the shell. In this work, eco-friendly AgInSe /AgInS core/shell QDs, which are optically active in the NIR region and are suitable candidates to fabricate devices for solar energy conversion, are developed.

Electrophoretic deposition of collagen/chitosan films with copper-doped phosphate glasses for orthopaedic implants.

Coatings with bioactive properties play a key role in the success of orthopaedic implants. Recent studies focused on composite coatings incorporating biocompatible elements that can increase the nucleation of hydroxyapatite (HA), the mineral component of bone, and have promising bioactive and biodegradable properties. Here we report a method of fabricating composite collagen, chitosan and copper-doped phosphate glass (PG) coatings for biomedical applications using electrophoretic deposition (EPD).

Stand-Alone CuFeSe (Eskebornite) Nanosheets for Photothermal Cancer Therapy.

Two-dimensional CuFeSe nanosheets have been successfully obtained via solution-phase synthesis using a sacrificial template method. The high purity was confirmed by X-ray diffraction and the two-dimensional morphology was validated by transmission electron microscopy. The intense absorption in the 400-1400 nm region has been the basis for the CuFeSe nanosheets' photothermal capabilities testing.

Bidirectional Superionic Conduction in Surface-Engineered 2D Hexagonal Boron Nitrides.

We designed functionalized hexagonal boron nitride (FhBN) nanoflakes with high proton conductivity in both in- and through-plane directions as next generation polymer electrolyte membranes (PEMs) for energy storage and conversion systems. The synthesis and functionalization of hBN nanoflakes with sulfonic acid (SA) groups are obtained by one-step and liquid-phase exfoliation with excellent dispersibility and stability over a period of three months. The physico/chemical properties of FhBN nanoflakes were investigated by different spectroscopic and microscopic characterization, confirming chemical interactions between hBN lattice and SA groups.

Synergistic Effect of Plasmonic Gold Nanoparticles Decorated Carbon Nanotubes in Quantum Dots/TiO for Optoelectronic Devices.

Here, a facile approach to enhance the performance of solar-driven photoelectrochemical (PEC) water splitting is described by means of the synergistic effects of a hybrid network of plasmonic Au nanoparticles (NPs) decorated on multiwalled carbon nanotubes (CNTs). The device based on TiO-Au:CNTs hybrid network sensitized with colloidal CdSe/(CdSe S )/(CdS) core/alloyed shell quantum dots (QDs) yields a saturated photocurrent density of 16.10 ± 0.

Low-Cost, Air-Processed Quantum Dot Solar Cells via Diffusion-Controlled Synthesis.

Despite significant advances in the development of high-efficiency and stable quantum dot (QD) solar cells (QDSCs), recent synthetic and fabrication routes still require improvements to render QDSCs commercially feasible. Here, we describe a low-cost, industrially viable fabrication method of QDSCs under an ambient atmosphere (humid air and room temperature) using stable, high-quality, and small-sized PbS QDs prepared with low-cost, greener precursors [i.e.

Synthesis and optoelectronic properties of Cu3VSe4 nanocrystals.

The ternary chalcogenide Cu3VSe4 (CVSe) with sulvanite structure has been theoretically predicted to be a promising candidate for photovoltaic applications due to its suitable bandgap for solar absorption and the relatively earth-abundant elements in its composition. To realize the absorber layer via an inexpensive route, printed thin-films could be fabricated from dispersions of nano-sized Cu3VSe4 precursors. Herein, cubic Cu3VSe4 nanocrystals were successfully synthesized via a hot-injection method.

A colloidal heterostructured quantum dot sensitized carbon nanotube-TiO hybrid photoanode for high efficiency hydrogen generation.

Solar-driven photoelectrochemical (PEC) hydrogen (H) generation is a promising approach to harvest solar energy for the production of a clean chemical fuel. However, the low photon-to-fuel conversion efficiency and long-term stability of PEC devices are major challenges to be addressed to enable large-scale commercialization. Here we report a simple, fast and cost-effective approach to fabricate high efficiency and stable PEC devices for H generation, by fabricating a hybrid photoanode obtained by incorporating small amounts of multiwall carbon nanotubes (MWCNTs) into a TiO mesoporous film and sensitizing with colloidal heterostructured CdSe/(CdSeS)/(CdS) quantum dots (QDs).

Towards Long-Term Thermal Stability of Dye-Sensitized Solar Cells Using Multiwalled Carbon Nanotubes.

In this study, the effect of incorporating multiwalled carbon nanotubes (MWCNTs) on the thermal stability of dye-sensitized solar cells (DSSCs) was investigated. Under identical measurement conditions (aging at 80 °C for 240 h), DSSCs based on a bare TiO anode presented a significant loss in photoconversion efficiency (PCE), dropping to 59 % of their initial value, whereas the DSSCs based on a TiO -MWCNT nanocomposite anode attained a promising thermal stability with only 20 % loss of PCE. This degradation of cell performance is mainly associated with a dramatic reduction in the short-circuit current density (J ).

Dye-sensitized solar cells based on a push-pull zinc phthalocyanine bearing diphenylamine donor groups: computational predictions face experimental reality.

Computational studies have suggested that the integration of secondary amine as donor groups in the structure of unsymmetrical zinc phthalocyanine (ZnPc) should have positive effects on photovoltaic performance, once the molecule is integrated as light harvester in dye sensitized solar cells (DSSCs). Aiming at obtaining experimental confirmation, we synthesized a peripherally substituted push-pull ZnPc bearing three electron donating diphenylamine substituents and a carboxylic acid anchoring group and integrated it as sensitizer in TiO-based DSSCs. Detailed functional characterization of solar energy converting devices resulted in ruling out the original hypothesis.

Controlled synthesis of near-infrared quantum dots for optoelectronic devices.

We designed a facile approach for the synthesis of PbS quantum dots (QDs) using thiourea and lead acetate as sources of sulfur and lead, respectively. The sizes of the PbS QDs could be systematically controlled by simply adjusting the reaction parameters. Cd post-treatment via a cation exchange method was performed to increase the stability of QDs.

A Player Often Neglected: Electrochemical Comprehensive Analysis of Counter Electrodes for Quantum Dot Solar Cells.

The role played by the counter electrode (CE) in quantum dot sensitized solar cells (QDSSCs) is crucial: it is indeed responsible for catalyzing the regeneration of the redox electrolyte after its action to take back the oxidized light harvesters to the ground state, thus keeping the device active and stable. The activity of CE is moreover directly related to the fill factor and short circuit current through the resistance of the interface electrode-electrolyte that affects the series resistance of the cell. Despite that, too few efforts have been devoted to a comprehensive analysis of this important device component.

Metal-free organic dyes for TiO2 and ZnO dye-sensitized solar cells.

We report the synthesis and characterization of new metal-free organic dyes (namely B18, BTD-R, and CPTD-R) which designed with D-π-A concept to extending the light absorption region by strong conjugation group of π-linker part and applied as light harvester in dye sensitized solar cells (DSSCs). We compared the photovoltaic performance of these dyes in two different photoanodes: a standard TiO2 mesoporous photoanode and a ZnO photoanode composed of hierarchically assembled nanostructures. The results demonstrated that B18 dye has better photovoltaic properties compared to other two dyes (BTD-R and CPTD-R) and each dye has higher current density (Jsc) when applied to hierarchical ZnO nanocrystallites than the standard TiO2 mesoporous film.

ZnO@SnO2 engineered composite photoanodes for dye sensitized solar cells.

Layered multi-oxide concept was applied for fabrication of photoanodes for dye-sensitized solar cells based on ZnO and SnO2, capitalizing on the beneficial properties of each oxide. The effect of different combinations of ZnO@SnO2 layers was investigated, aimed at exploiting the high carrier mobility provided by the ZnO and the higher stability under UV irradiation pledged by SnO2. Bi-oxide photoanodes performed much better in terms of photoconversion efficiency (PCE) (4.

Effect of blocking layer to boost photoconversion efficiency in ZnO dye-sensitized solar cells.

The effect of a ZnO compact blocking layer (BL) in dye-sensitized solar cells (DSSCs) based on ZnO photoanodes is investigated. BL is generated through spray deposition onto fluorine-doped tin oxide (FTO) conducting glass before the deposition of a ZnO active layer. The functional properties of dye-sensitized solar cells (DSSCs) are then investigated as a function of the thickness of the BL for two different kinds of ZnO active layer, i.

Controlling photoinduced electron transfer from PbS@CdS core@shell quantum dots to metal oxide nanostructured thin films.

N-type metal oxide solar cells sensitized by infrared absorbing PbS quantum dots (QDs) represent a promising alternative to traditional photovoltaic devices. However, colloidal PbS QDs capped with pure organic ligand shells suffer from surface oxidation that affects the long term stability of the cells. Application of a passivating CdS shell guarantees the increased long term stability of PbS QDs, but can negatively affect photoinduced charge transfer from the QD to the oxide and the resulting photoconversion efficiency (PCE).