Calcium-Based Mineralized Hydrogels for Temporary Reinforcement and Conservation of Ancient Ivory Relics.

Ancient ivory serves as an important witness of time and historical events, offering highly significant insights into the fields of paleontology, mineralogy, materials science, and geochemistry. However, ancient ivory has undergone groundwater corrosion and has a loose porous structure and reduced mechanical strength due to being buried for a long time. Therefore, the temporary reinforcement and preservation of ancient ivory artifacts are a well-known challenge.

Dual Passivation Strategy for Highly Stable Blue-Luminescent CsPbBr Nanoplatelets.

Blue-emitting colloidal CsPbX (X = Br, Cl, or I) perovskite nanocrystals have emerged as one of the most fascinating materials for optoelectronic applications. However, their applicability is hindered by poor stability and a low photoluminescence efficiency. Herein, highly stable CsPbBr nanoplatelets exhibiting intense blue luminescence are fabricated by employing a strategy in which the morphology is regulated and the surface is subjected to dual passivation through the incorporation of zirconium acetylacetonate [Zr(acac)].

Luminescent Perovskite-Cross-Linked Polymer with Low Shrinkage and Excellent Stability.

When organic cross-linked polymers are combined with metal halide perovskite nanocrystals (PNCs) for realizing luminescent perovskite-polymer display materials, the stability of PNCs is enhanced and their shrinkage is suppressed. This work presents a feasible strategy for preparing CsPbBr nanocrystals (NCs) within a polydicyclopentadiene (PDCPD) thermosetting cross-linked resin matrix simultaneously via a one-step reaction. The obtained PDCPD@PNCs composite exhibits narrow peak half-widths (15-20 nm), high light transmittance (80%), low curing volume shrinkage (1.

Shell thickness-induced thermal dependence: highly sensitive core-shell CdSe/ZnS/POSS-based temperature probes.

Fluorescence nanothermometry based on quantum dots is a current research hotspot for novel non-contact temperature monitoring, and is of vital significance for the modulation and design of the sensing properties of sensors. Herein, a design strategy to modulate the temperature-sensing characteristics of quantum dots based on the thickness of a shell is proposed. In this study, CdSe/ZnS quantum dot/POSS-based temperature probe films with varying fluorescence characteristics were developed, and the influence of the ZnS shell on temperature sensing was examined by varying the thickness of the ZnS shell.

Controllable fabrication of well-shaped PMBA@CsPbBr nanoparticles for highly sensitive detection of HCl and HBr.

We report a facile two-step strategy to construct well-shaped PMBA@CsPbBr nanoparticles, with this strategy involving combining adsorption and controlled polymerization. The morphological evolution process and mechanism of formation of the nanoparticles were demonstrated, and the nanoparticles showed high sensitivity to corrosive acid gas. This work has provided an effective approach for fabricating well-structured perovskite-based nanocomposites.

Fabricating a type II heterojunction by growing lead-free perovskite CsAgBiBr on graphite-like g-CN nanosheets for enhanced photocatalytic CO reduction.

Perovskite-based photocatalysts have received significant attention for converting CO into fuels, such as CO, CH or long alkyl chains. However, the use of these catalysts is plagued by several limitations, such as poor stability, lead toxicity, and inadequate conversion efficiency due to the rapid recombination of carriers. Herein, a g-CN@CsAgBiBr (CABB) type II heterojunction photocatalyst has been prepared by growing lead-free CABB nanocrystals (10-14 nm) on the graphite-like carbon nitride (g-CN) nanosheet using the crystallization method.

Well-shaped poly(dimethylsiloxane)-based copolymer nanowires from spherical micelles kinetic shape evolution.

The formation of self-assembled arrays or superstructures from copolymers has attracted intense research interest. Herein, we propose a kinetic approach to form self-assembled nanowires using a PDMS-based block copolymer consisting of poly(dimethylsiloxane)--poly[2-(cinnamoyloxy)ethyl methacrylate] (PDMS--PCEMA). The copolymer was synthesized by using the macroinitiator PDMS-Br to initiate 2-(trimethylsiloxy)ethyl methacrylate (HEMA-TMS) ATRP, followed by hydrolysis of the TMS group and gradual esterification with cinnamoyl chloride.

CsPbBr perovskite quantum dots grown within Fe-doped zeolite X with improved stability for sensitive NH detection.

All-inorganic cesium lead halide (CsPbX, X = Cl, Br and I) perovskite quantum dots (QDs) have received enormous research interest because of their exceptional optoelectronic properties, but their low chemical stability under ambient conditions from inevitable defects restricts their practical applications. In an effort to enhance the stability of QDs, in this study, novel functional nanocomposites were fabricated by encapsulating perovskite QDs with zeolite X doped with iron ions. Focusing on the as-obtained nanocomposites labeled with QDs@Fe/X-, doping a reasonable amount of Fe ions can tremendously improve the order of perovskite lattices and reduce the halide vacancies.

Insight into a Bentonite-Based Hydrogel for the Conservation of Sandstone-Based Cultural Heritage: In Situ Formation, Reinforcement Mechanism, and High-Durability Evaluation.

Conservation of sandstone-based cultural heritage has attracted a great deal of interest. We propose herein a novel protecting strategy, via in situ fabrication of bentonite-based hydrogels (B-H) inside sandstones, where the bentonite-based hydrogels serve as the underlying cement. To create bentonite-based hydrogels with controllable structure, possessing good mechanical and anti-swelling properties, we have optimized forming time, appearance, and viscosity.

CsPbBr Perovskite Nanocrystal Grown on MXene Nanosheets for Enhanced Photoelectric Detection and Photocatalytic CO Reduction.

All-inorganic CsPbX (X = Cl, Br or I) perovskite nanocrystals have attracted extensive interest recently due to their exceptional optoelectronic properties. In an effort to improve the charge separation and transfer following efficient exciton generation in such nanocrystals, novel functional nanocomposites were synthesized by the growth of CsPbBr perovskite nanocrystals on two-dimensional MXene nanosheets. Efficient excited state charge transfer occurs between CsPbBr NCs and MXene nanosheets, as indicated by significant photoluminescence (PL) quenching and much shorter PL decay lifetimes compared with pure CsPbBr NCs.

Unusual Stability and Temperature-Dependent Properties of Highly Emissive CsPbBr Perovskite Nanocrystals Obtained from in Situ Crystallization in Poly(vinylidene difluoride).

All-inorganic cesium lead halide perovskite nanocrystals (CsPbX, X = Cl, Br, or I) present broad applications in the field of optoelectronics due to their excellent photoluminescence (PL), narrow spectral bandwidth, and wide spectral tunability. However, their poor stability limits their practical application. In this work, we successfully use an in situ crystallization strategy for growing and cladding CsPbBr perovskite nanocrystals in poly(vinylidene difluoride) (PVDF).

Stable Luminous Nanocomposites of Confined Mn-Doped Lead Halide Perovskite Nanocrystals in Mesoporous Silica Nanospheres as Orange Fluorophores.

Creating highly stable inorganic perovskite nanocrystals (CsPbX, where X = Cl, Br, and I) with excellent optical performance is challenging because their optical properties depend on their ionic structure and its inherent defects. Here, we present a facile and effective synthesis using a nanoconfinement strategy to grow Mn-doped CsPbCl nanocrystals embedded in dendritic mesoporous silica nanospheres (MSNs). The resulting nanocomposite is abbreviated as Cs(Pb /Mn)Cl@MSNs and can serve as the orange emitter for white light-emitting diodes (WLEDs).

White-Light-Emitting Melamine-Formaldehyde Microspheres through Polymer-Mediated Aggregation and Encapsulation of Graphene Quantum Dots.

Graphene quantum dot (GQD) encapsulated melamine-formaldehyde (MF) polymer microspheres with uniform particle size and tunable high-quality white-light emissions are prepared via a polymer-mediated GQD assembly and encapsulation strategy. In solution, GQDs are first aggregated with MF prepolymer through electrostatic interaction and further encapsulated inside the microspheres formed by polymerization of MF prepolymer under acid catalysis and heating. During this process, the aggregated GQDs are fixed in the MF polymer matrix with their emission extended from blue to full visible range, presenting bright white luminescence under ultraviolet excitation.

Design Rules for Self-Assembly of 2D Nanocrystal/Metal-Organic Framework Superstructures.

We demonstrate the guiding principles behind simple two dimensional self-assembly of MOF nanoparticles (NPs) and oleic acid capped iron oxide (Fe O ) NCs into a uniform two-dimensional bi-layered superstructure. This self-assembly process can be controlled by the energy of ligand-ligand interactions between surface ligands on Fe O NCs and Zr O (OH) (fumarate) MOF NPs. Scanning transmission electron microscopy (TEM)/energy-dispersive X-ray spectroscopy and TEM tomography confirm the hierarchical co-assembly of Fe O NCs with MOF NPs as ligand energies are manipulated to promote facile diffusion of the smaller NCs.

Templated self-assembly of one-dimensional CsPbX perovskite nanocrystal superlattices.

Ordered self-assembled arrays or superstructures of nanocrystals (NCs) have attracted intense research interest due to their ability to translate valuable nanoscale properties to larger length scales. Numerous techniques have been explored to induce self-assembly into various superstructures. Here we investigated a simple kinetic approach to form self-assembled one-dimensional perovskite CsPbX (X: halides) nanocrystal arrays templated inside a pod shaped inert lead sulfate (PbSO) scaffold.

Nanorod Suprastructures from a Ternary Graphene Oxide-Polymer-CsPbX Perovskite Nanocrystal Composite That Display High Environmental Stability.

Despite the exceptional optoelectronic characteristics of the emergent perovskite nanocrystals, the ionic nature greatly limits their stability, and thus restricts their potential applications. Here we have adapted a self-assembly strategy to access a rarely reported nanorod suprastructure that provide excellent encapsulation of perovskite nanocrystals by polymer-grafted graphene oxide layers. Polyacrylic acid-grafted graphene oxide (GO-g-PAA) was used as a surface ligand during the synthesis of the CsPbX perovskite nanocrystals (NCs), yielding particles (5-12 nm) with tunable halide compositions that were homogeneously embedded in the GO-g-PAA matrix.

Insight into the Ligand-Mediated Synthesis of Colloidal CsPbBr3 Perovskite Nanocrystals: The Role of Organic Acid, Base, and Cesium Precursors.

While convenient solution-based procedures have been realized for the synthesis of colloidal perovskite nanocrystals, the impact of surfactant ligands on the shape, size, and surface properties still remains poorly understood, which calls for a more detailed structure-morphology study. Herein we have systematically varied the hydrocarbon chain composition of carboxylic acids and amines to investigate the surface chemistry and the independent impact of acid and amine on the size and shape of perovskite nanocrystals. Solution phase studies on purified nanocrystal samples by (1)H NMR and IR spectroscopies have confirmed the presence of both carboxylate and alkylammonium ligands on surfaces, with the alkylammonium ligand being much more mobile and susceptible to detachment from the nanocrystal surfaces during polar solvent washes.

POSS end-capped diblock copolymers: synthesis, micelle self-assembly and properties.

Polyhedral oligomeric silsesquioxane (POSS) end-capped diblock copolymers are synthesized using aminopropylisobutyl POSS (ap-POSS-Br) to initiate atom transfer radical polymerization (ATRP) of methylmethacrylate (MMA) and methacrylisobutyl POSS (MA-POSS). Their chemical structures are confirmed as ap-POSS-PMMA152.0-b-P(MA-POSS)4.

Fabrication pentablock copolymer/silica hybrids as self-assembly coatings.

Novel organic/inorganic hybrid for coating material is prepared by the pentablock copolymer PDMS-b-(PMMA-b-PMPS)2 (PMMDMM) and SiO2 nanoparticles. PMMDMM is obtained via atom transfer radical polymerization (ATRP) by using polydimethylsiloxane (PDMS) as bifunctional macroinitiator. Poly 3-(trimethoxysilyl)propyl methacrylate (PMPS) is designed as the end block for facilitating the chemical bond of triethoxysilane (Si(OCH3)3) groups with SiO2 nanoparticles produced by tetraethyl orthosilicate (TEOS), and poly (methyl methacrylate) (PMMA) is designed as the middle block for improving the solubility and the film-forming ability of copolymer.

Well-defined inorganic/organic nanocomposite by nano silica core-poly(methyl methacrylate/butylacrylate/trifluoroethyl methacrylate) shell.

The novel inorganic/organic core-shell SiO2/P(MMA/BA/3FMA) nanocomposite for coating application is synthesized in this paper by seed emulsion polymerization, in which the inorganic phase is composed of nano-SiO2 modified by vinyl-trimethoxysilane (VMS) or γ-methacryloxy propyl trimethoxylsilane (MPMS), and the organic phase is made of terpolymer by 2,2,2-trifluoroethyl methacrylate (3FMA), methyl methacrylate (MMA), and n-butyl acrylate (BA). The chemical structure of SiO2/P(MMA/BA/3FMA) is characterized by FTIR. The effect of surfactant polyvinylpyrrolidone (PVP), sodium dodecyl sulfate (SDS)/octyl phenyl polyoxyethylene ether (TX-10), sodium dodecyl benzene sulfonate (SDBS)/TX-10 and sodium hexametaphosphate (SHMP) on the grafting ratio (GR) of VMS and MPMS, the dispersion of nano-SiO2 particles and the film properties of SiO2/P(MMA/BA/3FMA) are investigated by TGA, DLS, TEM, SEM, and XPS.