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Superelectrophilic monoanions [B12 (BO)11 ]- and [B12 (OBO)11 ]- , generated from stable dianions [B12 (BO)12 ]2- and [B12 (OBO)12 ]2- , show great potential for binding with noble gases (Ngs). The binding energies, quantum theory of atoms in molecules (QTAIM), natural population analysis (NPA), energy decomposition analysis (EDA), and electron localization function (ELF) were carried out to understand the B-Ng bond in [B12 (BO)11 Ng]- and [B12 (OBO)11 Ng]- . The calculated results reveal that heavier noble gases (Ar, Kr, and Xe) bind covalently with both [B12 (BO)11 ]- and [B12 (OBO)11 ]- with large binding energies, making them potentially feasible to be synthesized. Only [B12 (OBO)11 ]- could form a covalent bond with helium or neon but the small binding energy of [B12 (OBO)11 He]- may pose a challenge for its experimental detection.

First-principles calculations have been carried out for the 20-electron transition metal complexes (Cp)2TMO and their molecular wires (Cp = C5H5, C5(CH3)H4, C5(CH3)5; TM = Cr, Mo, W). The calculation results at the BP86/def2-TZVPP level reveal that the ground state is singlet and the optimized geometries are in good agreement with the experimental values. The analysis of frontier molecular orbitals shows that two electrons in the highest occupied molecular orbital HOMO-1 are mainly localized on cyclopentadienyl and oxygen ligands. Furthermore, the nature of the TM-O bond was investigated with the energy decomposition analysis-natural orbitals for chemical valence (EDA-NOCV). The attraction term in the intrinsic interaction energies ΔEint is mainly composed of two important parts, including electrostatic interaction (about 52% of the total attractive interactions ΔEelstat + ΔEorb) and orbital interaction, which might be the major determinant of the stability of these (Cp)2TMO complexes. All of the TM-O bonds should be described as electron-sharing σ single bonds [(Cp)2TM]+-[O]- with the contribution of 53-57% of ΔEorb and two π backdonations from the occupied p orbitals of oxygen ligands into vacant π* MOs of the [(Cp)2TM]+ fragments, which are 35-40% of ΔEorb. The results of bond order and interaction energy from EDA-NOCV calculations suggest the influence of the radius of TM and methyl in the interactions between TM and O in (Cp)2TMO. Additionally, the relativistic effects slightly amplify the strength of bonding with increasing ΔEorb for the EDA-NOCV calculations on three metal complexes (C5H5)2TMO. Finally, the geometries, electronic structures, and magnetics of infinitely extended systems, [(C5H5)TMO]∞, have also been explored. The results of the density of states (DOS) and band structure revealed that [(C5H5)CrO]∞ and [(C5H5)WO]∞ are semiconductors with the narrow bands, whereas [(C5H5)MoO]∞ behaves as metal.

Ligand engineering based on a closo-B12-cage has been practiced in this work to design a series of stable gas-phase dianions [B12(ECX)12]2− (E = N, P, and As; X = O, S, and Se) via ab initio calculations. The calculated second electron affinities ranging from 1.2 to 3.4 eV indicate that these dianions are electronically stable against electron auto-detachment. Their electronic structures were analyzed based on molecular orbitals and natural bond orbitals. We found that in these designer dianions, the ECX ligands bind the B12-cage via B–E covalent interactions. We simulated the photoelectron spectra of these dianions and discussed the potential application of [B12(NCX)12]2− (X = O, S, and Se) salts as electrolytes in Li- or Mg-ion batteries.

The coordination of 10-electron diatomic ligands (BF, CO N2) to iron complexes Fe(CO)2(CNArTripp2)2 [ArTripp2=2,6-(2,4,6-(iso-propyl)3C6H2)2C6H3] have been realized in experiments very recently (Science, 2019, 363, 1203-1205). Herein, the stability, electronic structures, and bonding properties of (E1E2)Fe-(CO)2(CNArTripp2)2 (E1E2=BF, CO, N2, CN-, NO+) were studied using density functional (DFT) calculations. The ground state of all those molecules is singlet and the calculated geometries are in excellent agreement with the experimental values. The natural bond orbital analysis revealed that Fe is negatively charged while E1 possesses positive charges. By employing the energy decomposition analysis, the bonding nature of the E2E1-Fe(CO)2(CNArTripp2)2 bond was disclosed to be the classic dative bond E2E1→Fe(CO)2(CNArTripp2)2 rather than the electron-sharing double bond. More interestingly, the bonding strength between BF and Fe(CO)2(CNArTripp2)2 is much stronger than that between CO (or N2) and Fe(CO)2(CNArTripp2)2, which is ascribed to the better σ-donation and π back-donations. However, the orbital interactions in CN-→Fe(CO)2(CNArTripp2)2 and NO+→Fe(CO)2(CNArTripp2)2 mainly come from σ-donation and π back-donation, respectively. The different contributions from σ donation and π donation for different ligands can be well explained by using the energy levels of E1E2 and Fe(CO)2(CNArTripp2)2 fragments.

Lithium-sulfur batteries with high-energy density are witnessed to be the most prospective next generation advanced batteries. Nonetheless, the existing issues of serious shuttle effect and insulat...

Designing highly active material to fabricate high-performance glucose sensor was great importance for diabetes treatment. In this work, we develop a novel nanocomposite composed of multilevel nanostructure with ultrathin CuxO nanoflakes anchored on Cu2O nanowires, directly on Cu foil and its application as non-enzymatic glucose sensor. Due to more active sites endowed by the ultrathin CuxO nanoflakes, the as-prepared CuxO nanoflakes/Cu2O nanowires@Cu nanoarray exhibit high sensitivity (3.59 mA mM−1 cm−2), low detection limit (0.69 μM), high selectivity, fast amperometric response (~ 2 s) and excellent reliability in human serum. And the sensitivity of ultrathin CuxO nanoflakes/Cu2O nanowires@Cu nanoarray was 1.9-fold than that of Cu2O nanowires@Cu nanoarray. Such novel multilevel nanoarray synthesized by convenient method provides a facile way to design metal oxide nanomaterial for promising non-enzymatic glucose sensor.

The reaction mechanism, ligand and norbornene effects, and origins of meta-selectivity in Pd/norbornene-catalyzed alkylation and arylation via C–H activation are theoretically elucidated by DFT computation. The reaction proceeds through six major steps: ortho-C–H activation, norbornene insertion into Pd–C bonds, meta-C–H activation, meta-C–C bond formation, β-carbon elimination, and protodemetallation. Both ortho-C–H and meta-C–H activations undergo a concerted metalation–deprotonation pathway. The meta-C–C bond formation, which is the selectivity-determining step, follows a Pd(IV) pathway via oxidative addition on a Pd(II) five-membered-ring intermediate. The oxidative addition of alkyl iodide adopts an SN2 pathway, whereas aryl iodide prefers concerted oxidative addition rather than the SN2 pathway. The Pd(II) pathway via meta-C–C reductive coupling on dinuclear palladium species is not the dominant pathway because of the low concentration of Pd(0)L2. For methylation, with norbornene and pyridine (or its derivative) as ligands, the C–C reductive coupling and C–C reductive elimination from the Pd(IV) intermediate are found to be the selectivity-determining steps for meta-functionalization and benzocyclobutene formation, respectively, whereas the use of large ligands such as acridine and quinoline-type ligands (L1 and L2) moves the selectivity-determining step back to the oxidative addition and the C–C reductive elimination steps on the Pd(II) intermediate. The geometric and electronic properties of L1 and L2 further suppress the benzocyclobutene formation by increasing the energy difference between meta-functionalization and benzocyclobutene formation. The combination of 2-carbomethoxynorbornene and L2 promotes meta-ethylation and -arylation by disfavoring the C–C reductive elimination steps from the Pd(II) and Pd(IV) intermediates as well as slightly favoring the oxidative addition step.

High-performance, nonprecious metal catalysts with special morphologies and easy-to-recycle properties are essential for the treatment of environmental pollutants. Herein, CoFe nanoparticle-decorated reduced graphene oxide (RGO) catalysts were designed and successfully fabricated, and the catalyst was then used to reduce 4-nitrophenol into 4-aminophenol. Outstanding catalytic properties with a reduction rate constant of 4.613 min-1 were achieved due to the synergistic properties of the CoFe metal alloy and the high-conductivity RGO components in the catalysts. In addition, the catalyst was conveniently recovered via magnets due to its inherent magnetic properties. The facile preparation, outstanding catalytic performance, structural stability, and low material costs make the CoFe/RGO nanocatalyst a promising candidate for potential applications in catalysis.

Novel electronic donor with polycyclic structure based on coumarin was designed and prepared. Pyrrolidine acting as an isolated group was introduced to the donor by the Buchwald-Hartwig amination reaction. Such a novel electronic donor demonstrated great electron-donating capability and an excellent isolation effect. Both chromophores exhibited a D-π-A-π-A molecular structure. Such a structure has great advantages in energy matching, dipole interaction, and electron transfer, compared to the single D-π-A structure. The chemical structures of novel chromophores based on this donor were characterized by 1H nuclear magnetic resonance spectroscopy, 13C nuclear magnetic resonance spectroscopy, and mass spectrometry. The largest electro-optic coefficients are approximately 31.2 and 42.6 pm/V for chromophores NLO-C and NLO-P, respectively, at 1310 nm; otherwise, both chromophores NLO-C and NLO-P exhibit high thermal decomposition temperatures, i.e., 276 and 237 °C, respectively.

Two-dimensional (2D) nanocomposites, based on graphene and transition metal oxides, hold great promise as high-performance electrode materials for next-generation lithium-ion batteries. Herein, a novel 2D CuO/RGO has been constructed by CuO ultrathin nanosheets and reduced graphene oxides (RGO) through in-situ oxidizing the Cu/RGO nanocomposite with hydrogen peroxide. CuO nanosheets with a thickness of 1.17–1.57 nm are uniformly and tightly anchored on the RGO surface without aggregation and thus the as-prepared CuO/RGO nanosheets electrode show strong interfacial coupling and fast electron transfer. Electrochemical characterizations reveal that the CuO/RGO nanocomposite electrode exhibits a remarkably enhanced cycling performance and rate performance. At the current density of 0.1C, the initial discharge capacity of 811 mAh/g has been delivered by CuO/RGO nanosheets electrode and the coulombic efficiency maintains 99.44% after 100 cycles. Moreover, the CuO/RGO nanosheets exhibit a stable specific capacity of 386 mAh/g after 200 cycles at 3C. In addition, the as-prepared CuO/RGO nanocomposite electrode exhibited excellent rate performance and lower charge transfer resistance. The current study presents a feasible route to fabricate nanosheets electrode materials for next-generation energy storage devices.

Ultrafine Ag nanoparticles with unique physicochemical properties have a wide potential catalytic application. Herein, a one-pot method based on UV irradiation was applied for the synthesis of Ag-hydrogel composite, in which ultrafine Ag nanoparticles with a mean size of 2.47 ± 0.26 nm were well dispersed in the hydrogel network. In addition, the as-prepared Ag-hydrogel composites showed great catalytic performance and stability in the reduction of 4-nitrophenol.

The application of templating and etching agents for the synthesis of mesoporous graphitic carbon nitride (mpg-C3N4) is not environmentally friendly, motivating attempts to develop a green and efficient strategy to construct mpg-C3N4 with improved photocatalytic performance. Herein, for the first time, we demonstrate a general carbonated beverage-assisted hydrothermally-reformed commercial melamine (MA) strategy for the synthesis of mpg-C3N4 nanosheets. Although the dosage of carbonated beverage (including Coca-Cola, Pepsi-Cola, Sprite and Fanta) is very small for the modification of MA precursors, the improvement in the photocatalytic activity of the mpg-C3N4 products is very remarkable. With the unique structural advantages for aligned energy bands and charge carrier migration, and numerous photocatalytic sites, the visible-light-driven photocatalytic hydrogen evolution rate (HER) of mpg-C3N4 nanosheets synthesized from a Coca-Cola-reformed MA precursor is 15.1 times higher than that of bulk g-C3N4, achieving an apparent quantum yield of 7.7% at 420 nm. Similarly, mpg-C3N4 nanosheets synthesized from Pepsi-Cola-, Sprite- and Fanta-reformed MA precursors also exhibit enhanced photocatalytic HERs.

Doping and exfoliation are effective strategies to improve the photocatalytic activity of bulk graphitic carbon nitride (g-C3N4). Therefore, it can be inferred that engineering element-doping and exfoliation into g-C3N4 would further enhance the photocatalytic performance. Herein, we demonstrated a KOH-assisted hydrothermal-reformed melamine strategy for achieving the simultaneous K-doping and exfoliation of g-C3N4. The as-synthesized K-doped g-C3N4 ultrathin nanosheets displayed much enhanced photocatalytic hydrogen evolution rate (HER) of about 13.1 times higher than that of the bulk g-C3N4 under visible-light irradiation, achieving an apparent quantum efficiency of 6.98% at 420 nm. The improved photocatalytic HER can be attributed to the high surface area offering numerous photocatalytic active sites, enlarged conductive band edge optimizing photoreduction potential, and K-doping promoting charge generation and separation as well as the long life-time of photogenerated carriers. This work would provide a promising way to integrate co-doping and exfoliation into new g C3N4 based materials.

A systematic first-principles study is performed to investigate the 20-electron transition metal complexes (CH)TM(EE) (TM = Cr, Mo, W; EE = CO, N, BF). The bond dissociation energy (De) based on (CH)TM(EE) → (CH)TM(EE) + EE indicates much lower thermodynamic stability of (CH)TM(N) because of poor binding ability of N ligands. For the thermodynamic stable (CH)TM(EE) complexes (TM = Cr, Mo, W; EE = CO, BF), their 20-electron nature is derived from their occupied nonbonding molecular orbital mainly donated by ligands. Furthermore, charge transfer from TMs to the CH ligands is revealed by the atoms in molecules (AIM) theory, leading to the positive charges of the TM atoms. On the other hand, the nature of the TM-E bond has been thoroughly analyzed by the energy decomposition analysis (EDA) method. The absolute value of interaction energies (|ΔE|) between (CH)TM(EE) and EE has the same trend as the corresponding bond dissociation energy and Wiberg bond orders of TM-E bonds, following the order W > Mo > Cr with same ligands and BF > CO with same TM. Additionally, the largest contribution to the ΔE values is the repulsive term ΔE. Similar contributions from covalent and electrostatic terms to the TM-E bonds were found, which can be described as the classic dative bond with nearly same σ and π contributions. The stronger σ donations and π backdonations in (CH)TM(BF) than in (CH)TM(CO) indicate much more stability of (CH)TM(BF).

Design and synthesis of environmentally friendly adsorbents with high adsorption capacities are urgently needed to control pollution of water resources. In this work, a calcium ion-induced approach was used to synthesize sodium alginate fibroid hydrogel (AFH). The as-prepared AFH has certain mechanical strength, and the mechanical strength is enhanced especially after the adsorption of heavy metal ions, which is very convenient for the recovery. AFH exhibited excellent adsorption performances for Cu2+, Cd2+, and Pb2+ ions and displayed very high saturated adsorption capacities (Qe) of 315.92 mg·g-1 (Cu2+), 232.35 mg·g-1 (Cd2+), and 465.22 mg·g-1 (Pb2+) with optimized pH values (3.0-4.0) and temperature (303 K). The study of isotherms and kinetics indicated that adsorption processes of heavy metal ions fitted well with the pseudo-second-order kinetics model and the Langmuir model. Pb2+ was found to have the strongest competitiveness among the three heavy metal ions. Thus, AFH has great application prospects in the field of heavy metal ions removing from wastewater.

Hydrogels as soft and wet materials have attracted much attention in sensing and flexible electronics. However, traditional hydrogels are fragile or have unsatisfactory recovery capability, which largely limit their applications. Here, a novel hydrogen bond based sulfuric acid–poly(acrylic acid) (PAA)/poly(vinyl alcohol) physical hydrogel is developed for addressing the above drawbacks. Sulfuric acid serves two functions: one is to inhibit the ionization of carboxyl groups from PAA chains to form more hydrogen bonds and the other is to provide conductive ions to promote conductivity of hydrogel. Consequently, the hydrogel obtains comprehensive mechanical properties, including extremely rapid self-recovery (strain = 1, instantly self-recover; strain = 20, self-recover within 10 min), high fracture strength (3.1 MPa), and high toughness (18.7 MJ m–3). In addition, we demonstrate this hydrogel as a stretchable ionic cable and pressure sensor to exhibit stable operation after repeated loadings. This work prov...

Better understanding the crystal-facet engineering of a crystal with tailored architecture has demonstrated a significant implication for rational design and synthesis of promising micro-/nanostructure. In the past decades, extensive investigations have been devoted to the development of cuprous oxide (Cu2O) crystals with tailored architectures, which can provide a meritorious platform for not only revealing the structure-property-performance relationship and but also improving the performances in their practical applications. Several previous reviews have mainly reported the partial summaries of the advances in facet-dependent properties of Cu2O crystals. However, a comprehensive summary on Cu2O crystals is lacking and highly desirable to further promote the development of function-oriented Cu2O-based micro-/nanostructures. In this review, we will comprehensively highlight the important progresses in Cu2O crystals with tailored architectures, including the synthetic strategies and corresponding growth mechanisms, the fundamental properties of different crystallographic facets, the functional modifications (including doping and hybridization), and their potential applications. Several urgent issues and perspective are also discussed.

A facile Cu2O-templated approach is demonstrated for the synthesis of hierarchical Ag-AgBr hollow nanucubes. The structural and morphological characterizations show that the as-prepared hollow Ag-AgBr nanocubes consist of dense nanotips, which exhibited an excellent photocatalytic activity under visible light due to the strong surface plasmon resonance (SPR) of Ag nanosturctures and the synergistic effect between Ag and AgBr. The photodegradation ability was evaluated by the degradation of the methyl orange (MO) dye under visible-light irradiation, showing that more than 90% of the MO could be decomposed in 20 min.

Facile synthesis of ultrathin two-dimensional metallic nanosheets with special physical and chemical properties is still challenging. In this work, ultrathin silver nanosheets were synthesized through the galvanic replacement reaction between silver nitrate and Cu microcages without using any surfactant at room temperature. The as-prepared Ag nanosheets (NSs) were concave and had a thickness of sub-10 nm. And the nanosheets exhibited excellent H2O2 detection property with a high sensitivity of about 320.3 uA mM−1 cm−2 and a low detection limit of 0.17 µM in a wide linear range of 5–6000 μM, and a fast response time (less than 2 s). Besides, the real-time detection of H2O2 induced from living HeLa and SH-SY5Y cells were also achieved, indicating the potential application of as-prepared Ag NSs in monitoring physiological and dynamic in-clinic pathological processes.

Doping protocols have been widely investigated due to their effectiveness in tuning the energy band gaps of photocatalysts for improved photocatalytic activity. Here, we demonstrated the efficient and facile hydrogen peroxide-assisted hydrothermal reforming of melamine to synthesize a new oxygen (O)-doped precursor that was then transferred to O-doped g-C3N4 nanosheets, with an increased conductive band edge compared to bulk g-C3N4, via direct thermal polymerization. Owing to synergistic interaction between the 2D ultrathin nanosheet structure with large surface area and the enhanced conductive band edge caused by appropriate oxygen doping, the as-synthesized O-doped g-C3N4 nanosheets showed highly enhanced photocatalytic hydrogen evolution activity, about 10.7 times higher than pristine C3N4 under visible light irradiation, achieving an apparent quantum yield of 13.04% at 420 nm. Significantly, this precursor pre-doping strategy might provide a promising pathway for preparing heteroatom-doped g-C3N4.

Ultrathin CuO nanorods have been readily synthesized by simply mixing Cu2+/OH−/ethanol with water at high temperature. Such CuO nanorods display high sensitivity, low detection limit, fast amperometric response and good selectivity, which might add greater value to non-enzymatic glucose detection.

Unusual designated-tailoring on the preferential growth of ZnO meso-/nanocrystals with different shapes and sizes was successfully achieved through a very facile precursor-hydrolysis process in a water/organic solvent system. The shape-evolution of ZnO from mesocrystal to nanocrystal was achieved by increasing the amount of water in the reaction system under otherwise the same conditions, which can be attributed to selective-capping and preferential growth mechanisms based on DFT calculations. Typically, nanoparticle-aggregated cone-like ZnO mesocrystals enclosed by curved (101) and flat (000) surfaces were prepared in a lower amount of water, while various ZnO crystals without curved (101) surfaces were synthesized in a higher amount of water. In particular, “surface heterojunctions” were constructed in cone-like ZnO mesocrystals with co-exposed curved (101) and flat (000) surfaces, and these displayed greater photocatalytic degradation of methyl orange dye compared to the ZnO nanocrystals. This investigation is of great significance to the synthesis of additive-free ZnO mesocrystals, and offers a good opportunity to understand the formation mechanism and fundamental significance of the preferential growth of ZnO mesocrystals. Importantly, it is believed that the water-induced synthetic strategy reported here could provide a promising way to design more and more metal oxide architectures with controllable morphologies.

A systematic first-principles study is performed to investigate the 20-electron transition metal complexes (C5H5)2TM(E1E2)2 (TM = Cr, Mo, W; E1E2 = CO, N2, BF). The bond dissociation energy (De) based on (C5H5)2TM(E1E2)2 → (C5H5)2TM(E1E2) + E1E2 indicates much lower thermodynamic stability of (C5H5)2TM(N2)2 because of poor binding ability of N2 ligands. For the thermodynamic stable (C5H5)2TM(E1E2)2 complexes (TM = Cr, Mo, W; E1E2 = CO, BF), their 20-electron nature is derived from their occupied nonbonding molecular orbital mainly donated by ligands. Furthermore, charge transfer from TMs to the C5H5 ligands is revealed by the atoms in molecules (AIM) theory, leading to the positive charges of the TM atoms. On the other hand, the nature of the TM-E1 bond has been thoroughly analyzed by the energy decomposition analysis (EDA) method. The absolute value of interaction energies (|ΔEint|) between (C5H5)2TM(E1E2) and E1E2 has the same trend as the corresponding bond dissociation energy and Wiberg bond orders of TM-E1 bonds, following the order W > Mo > Cr with same ligands and BF > CO with same TM. Additionally, the largest contribution to the ΔEint values is the repulsive term ΔEPauli. Similar contributions from covalent and electrostatic terms to the TM-E1 bonds were found, which can be described as the classic dative bond with nearly same σ and π contributions. The stronger σ donations and π backdonations in (C5H5)2TM(BF)2 than in (C5H5)2TM(CO)2 indicate much more stability of (C5H5)2TM(BF)2.

Novel nonlinear optical polymer based on poly(aryl ether ketone) was designed and prepared. Such kind of materials showed excellent water solubility and thermal properties, its onset decomposition temperature can reach 314 °C; glass transition temperature can reach 170 °C. Though the nonlinear optical coefficients (d33) is not very large at 1310 nm, just about 13.9 pm/V; such kind of materials show us a low absorption spectral window at red and infrared light area (wavelength longer than 650 nm). Under the laser of 1310 nm, the morphology of the poled films can be detected by second harmonic generation (SHG) scanning microscopy.

As a significant metal chalcogenide, copper sulfide (Cu2-xS, 0 < x < 1), with a unique semiconducting and nontoxic nature, has received significant attention over the past few decades. Extensive investigations have been employed to the various Cu2-xS micro-/nanostructures owing to their excellent optoelectronic behavior, potential thermoelectric properties, and promising biomedical applications. As a result, micro-/nanostructured Cu2-xS with well-controlled morphologies, sizes, crystalline phases, and compositions have been rationally synthesized and applied in the fields of photocatalysis, energy conversion, in vitro biosensing, and in vivo imaging and therapy. However, a comprehensive review on diversified Cu2-xS micro-/nanostructures is still lacking; therefore, there is an imperative need to thoroughly highlight the new advances made in function-directed Cu2-xS-based nanocomposites. In this review, we have summarized the important progress made in the diversified Cu2-xS micro-/nanostructures, including that in the synthetic strategies for the preparation of 0D, 1D, 2D, and 3D micro-/nanostructures (including polyhedral, hierarchical, hollow architectures, and superlattices) and in the development of modified Cu2-xS-based composites for enhanced performance, as well as their various applications. Furthermore, the present issues and promising research directions are briefly discussed.

Morphology control is expected to be an effective method to enhance the electrochemical properties of materials. In this work, zinc cation-mediated growth of Cu2O crystals was achieved via an aqueous chemical route at room temperature. Thus, by simply increasing the concentration of Zn2+, concave cube-like (C-Cu2O), porous (P-Cu2O), and hierarchical (H-Cu2O) Cu2O crystals were selectively obtained. The morphologies and structures of the as-prepared Cu2O crystals were characterized by SEM, TEM, XRD and XPS. The three materials were subsequently employed as active materials for the non-enzymatic detection of glucose. The H-Cu2O-based electrode exhibited the highest sensitivity (3076 μA mM−1 cm−2) in virtue of its highest surface area, while the P-Cu2O-based electrode showed the widest linear range (up to 24 mM). The reliability of the Cu2O-based glucose sensors was proved by determining their detection limit, response time, selectivity, and stability characteristics on human serum samples. This work provides a novel strategy for the morphology-controlled Zn2+-mediated fabrication of Cu2O crystals with different glucose sensing performances depending on their structures.

Cu2O cubes and octahedra which have different crystallographic facets have been used for the nonenzymatic glucose sensors. The electrode based on the Cu2O octahedra displays much higher sensitivity, wider linear range and lower detection limit than that of the cubes modified electrode, which could be attributed to the different atomic arrangements of the exposed surface.

With a 2-phenylpyridine(ppy)-type cyclometalated Ir(III) complex with –B(Mes)2 group Ir–B, the CN¯ ions can bind effectively with the boron atom in the –B(Mes)2 group to furnish CN¯ sensing ability through inducing phosphorescence changing of the concerned Ir(III) complex. Uniquely, with increasing the added amount of CN¯ ions, loose and tight binding between CN¯ and boron atom in the –B(Mes)2 group of Ir–B can occur in sequence to destabilize metal-to-ligand charge transfer (MLCT) excited states and then form new MLCT excited states in Ir–B. Accompanying this process, the red phosphorescence of Ir–B can be effectively quenched by adding CN¯ ions, while new yellow and green emission bands can appear in sequent with increasing the amount of added CN¯ ions, showing CN¯ sensing behavior with unique concentration distinguishing ability. In addition, the new phosphorescent CN¯ sensor can possess detection limit (DL) as low as 4.3 × 10−6 M and good selectivity to the CN¯ ions. Clearly, these results can provide important information for developing new CN¯ sensors with high performances.

Constructing isotype heterostructure is an effective way to promote the separation of photogenerated charge carriers for graphitic carbon nitride (g-C3N4). However, the interface derived from different source precursors is not good enough for the charge separation of g-C3N4/g-C3N4 isotype heterojunctions, resulting in a limited improvement of photocatalytic performance. Here, we presented a rational design and synthesis of the g-C3N4(bulk)/g-C3N4(nanosheet) (denoted as BCN/CNNS) isotype heterojunctions with tight interfaces for enhanced photocatalytic hydrogen evolution. Using glucose-modified melamine as the single-source precursor for the first time, an isotype heterojunction was in situ formed at the interface between bulk g-C3N4 and g-C3N4 nanosheet. Due to the enhanced visible light absorption and promoted charge carrier separation, the in situ formed BCN/CNNS isotype heterojunctions exhibited highly improved photocatalytic hydrogen evolution activity under visible light irradiation, which was 16.4 and 11.5 times than those of the bare BCN and CNNS, respectively. Such an in situ formed isotype heterojunction with tight interfaces originated from the thermal polymerization of single-source glucose-modified melamine would present a new avenue for developing efficient g-C3N4-based isotype heterojunction photocatalysts.

Novel etched Cu2O cubes with exposed {110} facets are synthesized via an oxidative etching method at room temperature. The photocatalytic performance indicates that these architectures show higher photocatalytic activity than that of the normal Cu2O cubes in the degradation of methylene orange.

Present paper investigated the effect of mercerization and silane treatments on the transverse thermal conduction properties of unidirectional abaca fiber–epoxy composite fabricated by resin transfer molding. As indicated by FTIR, XRD and SEM, the changes in chemical composition, crystalline and lumen structure of abaca fibers were introduced by chemical treatments. Transverse tensile test showed that the weakest linkage of unidirectional composite changed from interface between abaca fiber bundle and epoxy resin for untreated abaca fiber to interface between elementary fibers treated by mercerization and silanization. With the increasing of weakest linkages strength and the decreasing of void content, the transverse thermal conductivity (TCC) of the composite presents increasing trend. The changing of interfaces, cell wall and lumen derived from chemical treatments are the mainly factors affecting TTC. It was concluded that the abaca fiber composite with controllable transverse thermal conduction property can be designed by proper chemical treatment.

Polyhedral inorganic crystals exposed with controllable-index facets is as significant as size, composition, phase and crystallinity in determining their chemical and physical properties. To accurately tune the exposed facets and morphologies of crystals is imperative because a thorough understanding of the formation mechanism and unique performance has significant scientific value. Better understanding of the control of exposed facets would bring about new capability for us to design necessary structures for actual applications. This article presents recent research progress in the development of polyhedral Cu2O architectures, focusing on the expanding of crystal-facet-dependent properties. The challenge and prospects of polyhedral Cu2O architectures are discussed. The present article provides important scientific references and a basis for future work.

We have demonstrated a facile copper-templated approach for synthesis of nanoparticle-aggregated hollow gold microcages. The as-prepared gold microcages, as active substrates, exhibit remarkable surface-enhanced Raman scattering activity for 4-mercaptobenzoic acid.

An interesting morphology-evolution of Cu2O from cubic, edge-truncated cubic, edge- and corner-truncated octahedral, truncated octahedral, and finally to octahedral architectures was readily achieved by adjusting the concentration of hydroxyl. When evaluated for their photocatalytic performances, these polyhedral Cu2O crystals manifest shape-dependent properties.

We have demonstrated the significant evidence on a green synthesis for the ordered-aggregation-driven growth from surfactant-free one-dimensional (1D) CuO nanosubunits into dimension-controlled mesostructures (three-dimensional (3D) mesospindles and two-dimensional (2D) mesoplates) by an additive-free complex–precursor solution route. Structural and morphological evolutions were investigated by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM) and field-emission scanning electron microscopy (FESEM). The formation of CuO mesostructures here is essentially determined by the characteristic of [Cu(OH)4]2− precursors, and an oriented nanoparticle aggregation with tailoring shapes in different dimensions can be achieved in different concentration of reactants at higher reaction temperature. The 3D “layer-by-layer” growth of mesostructural CuO spindles is successfully synthesized in low concentrations of reagents, while the 2D “shoulder-by-shoulder” growth of mesostructural CuO plates is obtained in high concentrations of reagents. The study is of great importance in the bottom-up assembly of controllable ordering architectures, and offers a good opportunity to understand the fundamental significance for the investigation of the formation mechanism and growth process of surfactant-free CuO mesostructures with controllable aggregation-based behaviours. Additionally, we further demonstrated that such CuO mesocrystals could serve as a potential photocatalyst for the degradation of rhodamine B (RhB) under visible light irradiation in the presence of hydroxide water (H2O2). The results also suggest that these 3D mesostructural CuO spindles exhibit a higher adsorption and photocatalytic degradation of RhB than that of 2D mesostructural CuO plates.

We have demonstrated a facile protocol for the synthesis of CuS cages wholly exposed with nanotwinned building blocks via a sacrificial Cu2O template solution route. The as-prepared CuS cages exhibit higher photocatalytic activity for enhancing degradation of methylene blue.

Local electromagnetic enhancement excited from collective oscillations of free electrons on a highly roughened mental surface can induce greatly enhanced Raman scattering. Herein gold mesoparticles with various morphologies and highly roughened surfaces, including sea urchin-like, flower-like, star-like, meatball-like, and dendritic nanostructures are prepared using pentanol/water interface as a growth “bed”. The morphologies of the prepared gold mesoparticles are well controlled by varying the concentrations of additives such as gold ions, ascorbic acid (AA) and cetyltrimethylammonium bromide (CTAB). Due to the unique structures such as rough surface, high internal porosity as well as complex morphology, these as-prepared mesocrystals exhibit a remarkable performance in surface-enhanced Raman scattering (SERS) compared with polyhedral mesoparticles.

We have demonstrated a facile protocol for the synthesis of facet-selective growth of low-cost metal Cu nanoparticles on {111} facets of polyhedral 26-facet Cu2O architectures. The novel Cu–Cu2O heterogeneous architectures show better adsorption and photodegradation of methyl orange than those of the original Cu2O architectures.

A facile solution route has been developed to synthesize nanoparticle-aggregated octahedral copper hierarchical nanostructures. The formation of these novel octahedral copper hierarchical nanostructures can be attributed to a gas bubbles assisted aggregation mechanism. Based on the shape evolution and corresponding growth mechanism, it is believed that more and more copper crystals with novel hierarchical nanostructures could be obtained.

Palladium membrane with porous structure was synthesized through self-assembly of Pd nanoparticles (NPs) at the interface between water and pentanol under ambient condition. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images revealed that the as-synthesized Pd membrane presented nano-network structure with very high porosity. The porous Pd membrane exhibited well electrocatalytic activity and high sensitivity toward nonenzymatic glucose oxidation. It might have a promising outlook in the applications for glucose sensor due to its facility in preparation and well properties.

Bimetallic Ag/Au nanoparticles (NPs) with alloyed and core–shell structures were synthesized at a low temperature (75 °C) from the preformed gold and silver NPs in aqueous solution. The transmission electron microscope (TEM) mapping images, as well as the evolution of UV/vis spectroscopy, revealed that both the digestive ripening and Ostwald ripening were responsible for the formation of above structures during the heating process. Higher Ag ratios led to the growth of silver shell on the surface of Ag/Au alloy core, while lower Ag ratios tended to the formation of alloy particles. Interparticle diffusion, ligands and chemical potential were presumed to play important roles in the formation of alloyed and core–shell bimetallic Ag/Au NPs.

IS304 high temperature self-lubricating composites were prepared by ball milling and induction sintering with embedded BaF2/CaF2 and Ag particles as lubricants. In comparison to PM304 composites with the same composition, the friction coefficient of IS304 is slight lower than that of PM304 in the temperature range from 20 to 250 °C. However, the friction coefficient of IS304 dramatically decreases at 260–280 °C while the friction coefficient of PM304 dramatically decreases at 330–350 °C under the same test condition. The improved friction coefficient of IS304 composites in the temperature range from 260 to 340 °C is due to the formation of self-lubricating fluoride films. The existence of fluoride film on the worn surface of IS304 is attributed to the refinement of lubricants from 30–70 μm to less than 2 μm and the appropriate distribution of fluorides, which can lead to a higher temperature rise (flash temperature) at the instantaneous contacting surface in comparison to that of the PM304 under the same test condition. It is this considerably higher superficial temperature rise at the contacting surface that can effectively activate the self-lubrication property of the fluoride phase and subsequently induce the formation the lubricating film.

High dispersive copper nanoparticles were prepared by chemical reduction method using potassium borohydride as reducing agent. The effects of reactant ratio, concentration of CuSO4, reaction temperature, and dispersant on the size of product and conversion rate were studied. The morphologies of copper nanoparticles were characterized by scanning electron microscopy. The results show that the optimum process conditions are as follows: the molar ratio of KBH4 to CuSO4 is 0.75 (3:4), concentration of CuSO4 is 0.4 mol/L, reaction temperature is 30 °C, and dispersant is n-butyl alcohol. The average particles size of copper powders with spherical shape gained is about 100 nm.

In this paper, shape-controlled synthesis of well-defined truncated edge polyhedral Cu2O architectures, including truncated edge cubic and truncated edge octahedral Cu2O crystals with three pairs of {100} facets, four pairs of {111} facets, and six pairs of {110} facets, and {100} etched truncated edge cubic Cu2O crystals, were achieved via a facile template-free complex-precursor aqueous solution route. The growth process and mechanism of Cu2O crystals are discussed in detail. The appearance of various morphologies can be attributed to the selective oxidative etching and preferential growth on different facets of Cu2O crystals.

Ultrathin Pt-based PtM (M = Pd, Ru, Au, Fe) alloy nanowire networks could be facilely synthesized using a soft template formed by cetyltrimethylammonium bromide in a two-phase water−chloroform system. The as-synthesized Pt-based alloyed nanowires show the fcc crystal phase. They have an average diameter of ∼2.3 nm and form porous nanonetworks, which can be potentially used for a number of catalytic applications. It was found that PtRu alloy nanonetworks showed more efficient catalytic activity for the hydrogenation of azo bonds in methyl orange than that of PtPd, PtAu, and pure Pt.