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Promoting formic acid electrochemical oxidation through the dehydrogenation path is critical for the development of direct liquid fuel cells. Herein, we report the modification of intermetallic PtBi hexagonal nanoplates by depositing trace amounts of Pd atoms (PtBi@1.8% Pd HNPs) to obviously improve the selectivity of the dehydrogenation path instead of the dehydration path, achieving highly efficient formic acid electrocatalysis. Impressively, PtBi@1.8% Pd exhibits superior mass activity of 4.17 A mgPt+Pd−1, which is 27 and 9.6 times higher than that of commercial Pt/C and Pd black catalysts, respectively. During chronoamperometry measurements, PtBi@1.8% Pd maintains much higher mass activity than the benchmark catalysts. The excellent electrocatalytic performances are attributed to the synergetic effect between the tensile-strained/electronic-modified Pd and the electronic-modified intermetallic PtBi, providing a novel co-modification strategy to boost electrocatalysis.

The combinations of nano-ZnO with wood through simple and efficient physical methods to prepare environmentally friendly and versatile Nano-ZnO-coated Wood have important research and practical implications. In this paper, an environmentally friendly nano-ZnO-coated wood was prepared by physical magnetron sputtering using Pinus sylvestris L. var. mongholica Litv. The micro-characteristics, structure, wettability and colour change of the ZnO-coated wood were characterized and studied. For samples with a sputtering time of more than 3 min, the surface water contact angle exceeded 130° and had good hydrophobic properties. After a 168 h accelerated ultraviolet (UV) ageing test, the total colour difference (ΔE ∗) of the sample with a sputtering time of 75 min (200 °C) was 77% lower than that of the original wood. When the substrate was at 200 °C, the ZnO films deposited on the surface of the wood were evenly and densely arranged, forming almost a continuous film. It could be seen that the deposition of a nano-ZnO film on the surface of wood could significantly improve its hydrophobic properties and anti-UV photochromic properties.

Self-assembly of colloidal nanoparticles into ordered superstructures provides a promising route to create novel/enhanced functional materials. Much progress has been made in self-assembly of anisotropic nanoparticles, but the complexity and tunability of superstructures remain restricted by their available geometries. Here we report the controlled packing of nanodumbbells (NDs) with two spherical lobes connected by one rod-like middle bar into varied superstructure polymorphs. When assembled into two-dimensional (2D) monolayer assemblies, such NDs with specific shape parameters could form orientationally ordered degenerate crystals with a 6-fold symmetry, in which these NDs possess no translational order but three allowed orientations with a rotational symmetry of 120 degrees. Detailed analyses identify the distinct roles of subunits in the ND assembly: the spherical lobes direct NDs to closely assemble together into a hexagonal pattern, and the rod-like connection between the lobes endows NDs with this specific orientational order. Such intralayer assembly features are well maintained in the two-layer superstructures of NDs; however, the interlayer stackings could be adjusted to produce stable bilayer superstructures and a series of metastable moiré patterns. Moreover, in addition to horizontal alignment, these NDs could gradually stand up to form tilted or even vertical packing based on the delicate control over the liquid–liquid interface and ND dimensions. This study provides novel insights into creating superstructures by controlling geometric features of nanoscale building blocks and may spur their novel applications., Nanodumbbells were assembled into superstructures with three orientations, and distinct roles of individual subunits of nanodumbbells in the assembly are uncovered.

Pt-based ultrathin nanowires (NWs) are considered as one of the most intriguing catalysts for fuel cells. However, the delicate controllability of surface structure of ultrathin NWs to regulate their catalytic performances is still a challenge. Here, two kinds of one-nanometer-thick Pt-based NWs with smooth surfaces (S-NWs) and rough surfaces (R-NWs) are demonstrated, in which the combined use of hexadecyltrimethylammonium bromide and oleylamine plays an essential role, as they could form soft-templates to direct the growth of NWs. Due to its high-density of low-coordinated sites on the surface, Pt-based R-NWs exhibit higher oxygen reduction reaction (ORR) activities but lower stabilities than corresponding S-NWs. Notably, Pt0.78Ni0.22 R-NWs possess the highest mass activity (1.07 A·mgPt−1) and specific activity (1.02 mA·cm−2) among all Pt-based NWs. After 10,000 sweeping cycles, the mass activity still exhibits 5.7-fold enhancement compared to the corresponding commercial Pt/C. This work presents a new approach to delicately control the surface structure of ultrathin Pt-based NWs as advanced ORR catalysts.

The limited electrochemical activities of Pt-based catalysts lead to the sluggish kinetics of the ethanol oxidation reaction (EOR). The delicate combination between SnO2 and Pt-based nanocatalysts could effectively resolve this problem. Herein, SnO2 patched ultrathin PtRh nanowires (PtRh@SnO2 NWs) are synthesized by depositing and oxidizing Sn atoms on the surface of pre-formed PtRh NWs. Based on this method, SnO2 patched ultrathin Pt, PtNi and PtRu NWs are produced as well by using different NW templates. Benefiting from the close proximity between Pt, Rh and amorphous SnO2 patches, the oxidation of intermediates is enhanced, which is critical to boost the EOR electrocatalysis. Electrochemical measurements show that, compared with the other SnO2 patched ultrathin Pt-based NWs, ultrathin PtRh@SnO2 NWs with 40.7 at% SnO2 exhibit the greatest mass activity of 3.16 A mg−1 and specific activity of 5.63 mA cm−2 towards the EOR in alkaline electrolyte, which are 5.3 and 4.3 times higher than those of commercial Pt/C, respectively. This work highlights the role of the structure and composition of ultrathin PtRh@SnO2 NWs in boosting EOR electrocatalysis, and offers new insights into the design of advanced catalysts for broad application.

Sn-Based materials are considered as promising anode materials for lithium ion batteries due to their high theoretical capacities; however, aggregation of electrochemically active particles and pulverization resulting from huge volume changes during alloying/dealloying severely limit their performance. To solve these problems, nanosized and hollow structures have been proposed. Herein, uniform solid Sn nanoparticles and hollow/amorphous SnOx nanospheres are prepared accordingly and their electrochemical performances as anode materials in lithium ion batteries have been evaluated. Uniform solid Sn nanoparticles deliver a capacity of 416.4 mA h g−1 for 400 cycles at a current of 500 mA g−1, corresponding to a high capacity retention of 81.1%. Furthermore, hollow/amorphous SnOx nanospheres show a high capacity retention of 81.3% for 400 cycles at a current of 500 mA g−1 and exhibit a good rate capability (retains 58.0% of the capacity at 1000 mA g−1 with respect to 100 mA g−1). It is believed that their good electrochemical performances mainly originate from their small sizes (

The Liaotianjianshan kiln dates back to ca. 3700 years ago as a typical kiln used to manufacture proto-porcelain and stamped stoneware. In this paper, 22 ceramic shard samples from Liaotianjianshan kiln sites were selected to be analyzed by XRF, EMPA-WDS and DIL. The results indicated that the two types of samples have similar chemical characteristics in the body and the consistent firing temperature. The element composition of the kiln sites had low iron and calcium content, which was different from the materials from other areas. The samples had high calcium glazes. Two different types of glaze recipes were distinguished by the content of the minor elements, which also corresponded to the changes in the glaze color. The regular change of the glaze composition and the color reflected an advanced ability of the craftsman to control the glaze recipes. The ceramic properties and the technical maturity revealed that the manufacturing technology of the proto-porcelain of the Liaotianjianshan sites were in the leading level in Southern China during Xia and Shang periods, and Quanzhou seems to be one of the original producing locations of proto-porcelain within China.

The rational design and control of electrocatalysts at single-atomic sites could enable unprecedented atomic utilization and catalytic properties, yet it remains challenging in multimetallic alloys. Herein, the first example of isolated Rh atoms on ordered PtBi nanoplates (PtBi-Rh1 ) by atomic galvanic replacement, and their subsequent transformation into a tensile-strained Pt-Rh single-atom alloy (PtBi@PtRh1 ) via electrochemical dealloying are presented. Benefiting from the Rh1 -tailored Pt (110) surface with tensile strain, the PtBi@PtRh1 nanoplates exhibit record-high and all-round superior electrocatalytic performance including activity, selectivity, stability, and anti-poisoning ability toward ethanol oxidation in alkaline electrolytes. Density functional theory calculations reveal the synergism between effective Rh1 and tensile strain in boosting the adsorption of ethanol and key surface intermediates and the CC bond cleavage of the intermediates. The facile synthesis of the tensile-strained single-atom alloy provides a novel strategy to construct model nanostructures, accelerating the development of highly efficient electrocatalysts.

Multifunctional spherical aggregated gold nanoclusters encapsulated by polyacrylic acid/mesoporous silica shell nanoparticles (A-AuNC@PAA/mSiO2 NPs) with aggregation enhanced fluorescence (AEF) properties were fabricated by a facile and reproducible synthetic strategy. The as-prepared NPs were employed as novel theranostic agents for synergistic fluorescence/X-ray computed tomography imaging and chemo-therapy of liver cancer in vitro and in vivo.

Herein, five kinds of soluble electrochromic polyarylates were synthesized from the reaction of N,N'-bis(4-carboxyphenyl)-N,N'-di-2-naphthyl-1,4-phenylenediamine with five bisphenols via direct polycondensation process, respectively. These new materials showed no significant decomposition below 400 °C in nitrogen atmosphere. The maximum UV–vis absorption bands of these polyarylates located at 328–348 nm and 327–353 nm for solid films and DMSO solution, respectively. The polyarylate 6a , as an example, exhibited not only aggregation-induced emission (AIE) effect in different fraction tetrahydrofuran/water solution, but also solvatochromism in various polar solvents, markedly. Two reversible pairs of distinct redox peaks were associated with noticeable color changed from original colorless to yellowish orange and green for polymeric film could be observed in the cyclic voltammetry (CV) test. New absorption peaks emerged in near–infrared (NIR) region with increasing voltage in the UV–vis spectra, which indicates these polyarylates can be used as NIR electrochromic materials. These polyarylates performed high contrast of optical transmittance change around 42–53% with the highest coloration efficiency up to 236 cm 2 C −1 .

Two series of novel aromatic polyamides (PAs) were synthesized via polymer condensation reaction based on N,N'-bis(4-aminophenyl)-N,N'-di-1-naphthalenyl-[1,1′-biphenhyl]-4,4′-diamine, N,N'-bis(4-aminophenyl)-N,N'-diphenyl-4,4′-biphenyl diamine and different binary acids compounds. The structures of the monomers and polymers were characterized by Fourier transform infrared spectroscopy (FT-IR), hydrogen nuclear magnetic resonance (1H NMR). The electrochromic properties of the PAs were investigated by using the ultra-visible-near infrared (UV–Vis–NIR) spectrophotometer and electrochemical workstation. The color of the polymer films changed from light yellowish to brown, then atroceruleous or brilliant blue with an increasing potential. Then we discussed the relationship of morphology on coloration efficiency. The electrochemical impedance spectroscopy (EIS) also has been used to characterize the internal resistances of PAs film electrodes.

We report a mild synthetic method to access Sn nanocrystals with tunable diameter and narrow size distribution (6–8%). The self-templated formation of various types of Sn chalcogenide hollow nanostructures including oxides, sulfides, selenides, and tellurides is also demonstrated for the first time. The use of air-stable tungsten hexacarbonyl that produces carbon monoxide at elevated temperature to reduce the SnCl2 precursor and coordinate the nanoparticle surface is thought to play an essential role in this method. This synthesis method is likely to be extended to other metal systems and could find potential applications including battery anodes and catalysts.

We have developed a method to fabricate freestanding highly ordered porous silver (Ag) superstructures by an "assembly-based nanoparticle (NP) coalescence" method. The synthesized superstructures have high-density mesopores periodically distributed over the entire structure, on which a highly enhanced electromagnetic field was observed by electron energy loss spectroscopy. Thus, the surface enhanced Raman scattering (SERS) signal of Rhodamine 6G in the ordered mesopores is 8.2 times higher compared to that in disordered porous superstructures. The results demonstrate that these freestanding mesoporous Ag superstructures are potentially good SERS substrates.

Platinum is the most effective metal for a wide range of catalysis reactions, but it fails in the formic acid electrooxidation test and suffers from severe carbon monoxide poisoning. Developing highly active and stable catalysts that are capable of oxidizing HCOOH directly into CO2 remains challenging for commercialization of direct liquid fuel cells. A new class of PtSnBi intermetallic nanoplates is synthesized to boost formic acid oxidation, which greatly outperforms binary PtSn and PtBi intermetallic, benefiting from the synergism of chosen three metals. In particular, the best catalyst, atomically ordered Pt45 Sn25 Bi30 nanoplates, exhibits an ultrahigh mass activity of 4394 mA mg-1 Pt and preserves 78% of the initial activity after 4000 potential cycles, which make it a state-of-the-art catalyst toward formic acid oxidation. Density functional theory calculations reveal that the electronic and geometric effects in PtSnBi intermetallic nanoplates help suppress CO* formation and optimize dehydrogenation steps.

2D mesoporous materials fabricated via the assembly of nanoparticles (NPs) not only possess the unique properties of nanoscale building blocks but also manifest additional collective properties due to the interactions between NPs. In this work, reported is a facile and designable way to prepare free-standing 2D mesoporous gold (Au) superstructures with a honeycomb-like configuration. During the fabrication process, Au NPs with an average diameter of 5.0 nm are assembled into a superlattice film on a diethylene glycol substrate. Then, a subsequent thermal treatment at 180 °C induces NP attachment, forming the honeycomb-like ordered mesoporous Au superstructures. Each individual NP connects with three neighboring NPs in the adjacent layer to form a tetrahedron-based framework. Mesopores confined in the superstructure have a uniform size of 3.5 nm and are arranged in an ordered hexagonal array. The metallic bonding between Au NPs increases the structural stability of architected superstructures, allowing them to be easily transferred to various substrates. In addition, electron energy-loss spectroscopy experiments and 3D finite-difference time-domain simulations reveal that electric field enhancement occurs at the confined mesopores when the superstructures are excited by light, showing their potential in nano-plasmonic applications.

Engineering a facile and controllable approach to modulate the spectral properties of lanthanide-doped upconversion nanoparticles (UCNPs) is always an ongoing challenge. Herein, long-range ordered, distinct two-dimensional (2D) binary nanoparticle superlattices (BNSLs) composed of NaREF4 :Yb/Er (RE = Y and Gd) UCNPs and plasmonic metallic nanoparticles (Au NPs), including AB, AB3 , and AB13 lattices, are fabricated via a slow evaporation-driven self-assembly to achieve plasmonic modulation of upconversion luminescence (UCL). Optical measurements reveal that typical red-green UCL from UCNPs can be effectively modulated into reddish output in BNSLs, with a drastically shortened lifetime. Notably, for AB3 - and AB13 -type BNSLs with more proximal Au NPs around each UCNP, modified UCL with fine-structured spectral lineshape is observed. These differences could be interpreted by the interplay of collective plasmon resonance introduced by 2D periodic Au arrays and spectrally selective energy transfer between UCNPs and Au. Thus, fabricating UCNP-Au BNSLs with desired lattice parameters and NP configurations could be a promising way to tailor the UCL through controlled plasmonic modulation.

Engineering novel Sn-based bimetallic materials could provide intriguing catalytic properties to boost the electrochemical CO2 reduction. Herein, the first synthesis of homogeneous Sn1- x Bix alloy nanoparticles (x up to 0.20) with native Bi-doped amorphous SnOx shells for efficient CO2 reduction is reported. The Bi-SnOx nanoshells boost the production of formate with high Faradaic efficiencies (>90%) over a wide potential window (-0.67 to -0.92 V vs RHE) with low overpotentials, outperforming current tin oxide catalysts. The state-of-the-art Bi-SnOx nanoshells derived from Sn0.80 Bi0.20 alloy nanoparticles exhibit a great partial current density of 74.6 mA cm-2 and high Faradaic efficiency of 95.8%. The detailed electrocatalytic analyses and corresponding density functional theory calculations simultaneously reveal that the incorporation of Bi atoms into Sn species facilitates formate production by suppressing the formation of H2 and CO.

0D lead-free metal halide nanocrystals (NCs) are an emerging class of materials with intriguing optical properties. Herein, colloidal synthetic routes are presented for the production of 0D Cs3 Cu2 X5 (X = I, Br, and Cl) NCs with orthorhombic structure and well-defined morphologies. All these Cs3 Cu2 X5 NCs exhibit broadband blue-green photoluminescence (PL) emissions in the range of 445-527 nm with large Stokes shifts, which are attributed to their intrinsic self-trapped exciton (STE) emission characteristics. The high PL quantum yield of 48.7% is obtained from Cs3 Cu2 Cl5 NCs, while Cs3 Cu2 I5 NCs exhibit considerable air stability over 45 days. Intriguingly, as X is changed from I to Br and Cl, Cs3 Cu2 X5 NCs exhibit a continuous redshift of emission peaks, which is contrary to the blueshift in CsPbX3 perovskite NCs.

Colloidal nanocrystals (NCs) have become an important group of novel materials with applications in various fields such as lighting, medicine, and optoelectronic devices. Compared to common semiconductor NCs (e.g., CdSe, CdS, PbS) with covalent bonds and metal NCs (e.g., Au, Ag, Pt) with metallic bonds, the synthesis of colloidal NCs with ionic bonds has rarely been explored, possibly due to their high solubility in polar solvents. In this work, we demonstrate a wet chemical synthesis route to prepare ionic cesium iodide (CsI) colloidal NCs, and they can be controllably made into different morphologies with good uniformity, including nanospheres, hexagonal nanoplates and nanocubes. The degradation of CsI NCs during transmission electron microscopy (TEM) has been investigated, revealing their sensitivity to high energy electron beam irradiation. The as-prepared CsI NCs exhibit strong absorption bands peaking at 275–280 nm, which should be ascribed to the presence of F-centers inside the band gap of CsI NCs. This study provides an efficient way to achieve controllable synthesis of high-quality CsI NCs that may find promising applications as advanced nanoscintillators in medical imaging, particle physics, position emission tomography and other various fields.

Engineering novel theranostic agents with both imaging and therapeutic functions have profound impact on molecular diagnostics, imaging, and therapeutics. In this paper, we develop for the first time a simple, scalable, and reproducible route to synthesize novel multifunctional spherical Au nanoclusters assemblies encapsulated by a polyacylic acid (PAA)/calcium phosphate (CaP) shell with aggregation enhanced fluorescence property (designated as AuNCs-A@PAA/CaP). Furthermore, the resulting AuNCs-A@PAA/CaP nanoparticles (NPs) possess a high payload of doxorubicin as synergetic pH-sensitive drug delivery vehicles to employ for dual-modal computed tomography (CT) and fluorescence imaging-guided liver cancer chemotherapy in vivo. The results reveal that AuNCs-A@PAA/CaP NPs not only provide excellent bimodal CT and fluorescence contrast imaging but also present efficient tumor ablation under the guidance of CT and fluorescence imaging, to achieve excellent chemotherapeutic efficacy to the hepatocarcinoma cell line (H-22) bearing mice through intravenous injection. Comprehensive blood tests and careful histological examinations reveal no apparent toxicity of AuNCs-A@PAA/CaP NPs. Our work highlights the great promise of AuNCs-A@PAA/CaP NPs for guiding and monitoring the chemotherapeutic process using simultaneous dual-modality CT and fluorescence imaging through a single theranostic agent.

Two novel series of triphenylamine (TPA)-containing aromatic polyurethanes (PUs) were synthesized via polymerization of N′,N′-bis(α-naphthyl)-N,N′-bis(4-phenylisocyanate) biphenyl (M1) and N,N′-diphenyl-N,N′-bis(4-phenylisocyanate) biphenyl (M2) with different dihydroxy compounds. The structures of the polymers were characterized by Fourier transform infrared (FT-IR) spectroscopy, hydrogen nuclear magnetic resonance (1H-NMR) and carbon nuclear magnetic resonance (13C-NMR); and the thermostability and morphology were studied by thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). The molecular weights were measured to be from 1.02 × 104 to 1.31 × 104 by gel permeation chromatography (GPC). The polymers were coated onto indium tin oxide (ITO) and the electrochromic properties were investigated by using the ultraviolet visible (UV-vis) absorption spectra and cyclic voltammetry (CV). The energy gaps were in the range of 2.21–2.26 eV. The polymer films revealed good stability of the electrochromic characteristics by continuous cyclic scans, with the color changing from neutral yellowish to a blue doped form at applied potentials. Meanwhile, the PUs film exhibited non-volatile write-once-read-many-times (WORM) memory behavior in the device resulting from the non-isolated donor–acceptor (D–A).

Hydrogel neural interface mimics the living environment of neurons mechanically, chemically, and electrically, incurs much less immunochemical rejection than commonly used metallic electrodes (platinum and silver). It readily records local field potentials and individual spikes in vivo. In optogenetic experiments, a single fiber of the hydrogel can function as both an optic fiber and an ionic conductor, co-locating the site of laser stimulation and electrical recording.

A facile two-step strategy was developed to fabricate yellow fluorescent glutathione-Au nanoclusters/zeolitic imidazolate framework-8 nanoparticles (GSH-Au NCs/ZIF-8 NPs) and their derived Au/ZnO NPs, which exhibited visible light photocatalytic hydrogen evolution together with degradation of Rhodamine B (RhB).

The polyacrylic acid@zeolitic imidazolate framework-8 (PAA@ZIF-8) nanoparticles (NPs) were first fabricated using a facile and simple route. It is worthwhile noting that the as-fabricated PAA@ZIF-8 NPs possessed ultrahigh doxorubicin (DOX) loading capability (1.9 g DOX g(-1) NPs), which were employed as pH-dependent drug delivery vehicles.

A universal method was utilized to fabricate rhombic dodecahedral zeolitic imidazolate framework-8@SiO2 (ZIF-8@SiO2) nanoparticles (NPs) and their derivatives, ZnO@SiO2, ZIF-8@SiO2 yolk–shell and SiO2 hollow NPs, using ZIF-8 NPs as the template.

A facile two-step method was developed to fabricate green fluorescent carbon nanodots@zeolitic imidazolate framework-8 nanoparticles (C-dots@ZIF-8 NPs) with tunable size and fluorescence intensity, which acted as platforms for simultaneous pH-responsive drug delivery and fluorescence imaging of cancer cells.