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Fabricating proton exchange membranes (PEMs) with high ionic conductivity and ideal mechanical robustness through regulation of the membrane microstructures achieved by molecular-level hybridization remains essential but challenging for the further development of high-performance PEM fuel cells. In this work, by precisely hybridizing nano-scaled bismuth oxide clusters into Nafion, we have fabricated the high-performance hybrid membrane, Nafion-Bi12 -3 %, which showed a proton conductivity of 386 mS cm-1 at 80 °C in aqueous solution with low methanol permeability, and conserved the ideal mechanical and chemical stabilities as PEMs. Moreover, molecular dynamics (MD) simulation was employed to clarify the structural properties and the assembly mechanisms of the hybrid membrane on the molecular level. The maximum current density and power density of Nafion-Bi12 -3 % for direct methanol fuel cells reached to 432.7 mA cm-2 and 110.2 mW cm-2 , respectively. This work provides new insights into the design of versatile functional polymer electrolyte membranes through polyoxometalate hybridization.

Background During the last decade buckwheat was reported to have positive health effects. The present study investigated a high-polyphenol buckwheat protein (Fagopyrum esculentum Moench) prepared by enzyme-assisted processing, together with its physicochemical properties, in vitro digestibility, and antioxidant activity. Results Buckwheat protein prepared from the synergistic enzymatic action of α-amylase and amyloglucosidase (E-BWP) had much higher polyphenol content than buckwheat protein prepared by isoelectric precipitation (I-BWP) or salt extraction (S-BWP). Rutin degraded during the process, giving quercetin. The protein constituents and amino acid composition of E-BWP were very similar to those of native buckwheat and were able to meet the WHO/FAO requirements for both children and adults. During in vitro digestion, E-BWP showed anti-digestive behavior with a nitrogen release that was lower than that of I-BWP or S-BWP. The positive effect of the polyphenol content of E-BWP resulted in a higher 1,1-diphenyl-2-picrylhydrazyl (DPPH) content and greater reducing activity. Conclusion Buckwheat protein with high polyphenol content was successfully developed by enzyme-assisted processing. It had a well-balanced amino acid profile, antidigestive behavior, and high antioxidant activities. The results suggest that enzyme-assisted processing is promising in the production of polyphenol-enriched cereal protein, contributing higher functionality with good nutritional and antioxidant properties. © 2018 Society of Chemical Industry.

The rational design and development of efficient and affordable enzyme-free electrocatalysts for electrochemical detection are of great significance for the large-scale applications of sensor materials, and have aroused increasing research interest. Herein, we report that a typical polyoxometalate (POM)-based metal-organic framework (NENU5) that was hybridized with ketjenblack (KB) was a highly efficient electrochemical catalyst that could be used for the highly sensitive nonenzymatic detection of H2 O2 . The composite catalyst exhibited superb electrochemical detection performance towards H2 O2 , including a broad linear range from 10-50 mm, a low detection limit of 1.03 μm, and a high sensitivity of 33.77 μA mm-1 , as well as excellent selectivity and stability. These excellent electrocatalytic properties should be attributed to the unique redox activity of the POM, the high specific surface area of the metal-organic framework (MOF), the strong conductivity of KB, and the synergistic effects of the multiple components in the composites during the electrolysis of H2 O2 . This work provides a new pathway for the exploration of nonenzymatic electrochemical sensors.

The hydrogen evolution reaction (HER) produces clean hydrogen through an electrochemical process. However, new nonprecious-metal electrocatalysts for the HER are required to reduce the consumption of energy. Herein, we report a new Co2 P/WC nano-heterojunction that consists of Co2 P and WC composite phases coated with a few-layer N-doped graphitic carbon shells (Co2 P/WC@NC). The composite was prepared by a one-step annealing of the polyoxometalate Na9 (NH4 )5 [{(B-α-PW9 O34 )Co3 (OH)(H2 O)2 (Ale)}2 Co]⋅35 H2 O (Co7 P6 W18 ) and dicyandiamide (DCA). The preparation method consisted of the simultaneous phosphorization of Co and carbonization of W in a confined space to isolate a Co2 P/WC nano-heterojunction phase for the first time. Co2 P/WC@NC facilitated the generation of hydrogen in the electrolysis process, which had an overpotential of only 91 mV at a current density of 10 mA cm-2 in the acid solution; an excellent HER performance (2 H+ +2 e- →H2 ) and Tafel slope (40 mV dec-1 ) as well as durability over a period of 50 h were achieved. Theoretical calculations showed that the Co2 P, WC, and Npyridinic C dopants in the material synergistically promoted the HER activity rather than the individual constituents. Furthermore, Co2 P/WC@NC nano-heterojunctions showed good HER performance in the whole pH range of electrolytes and considerable durability in acidic media containing transition metal ions, which may attract more attention for the exploration and optimization of nano-heterojunction catalysts for the HER.

The loading of noble-metal nanoparticles (NMNPs) onto various carriers to obtain stable and highly efficient catalysts is currently an important strategy in the development of noble metal (NM)-based catalytic reactions and their applications. We herein report a nanowire supramolecular assembly constructed from the surfactant-encapsulating polyoxometalates (SEPs) CTAB-PW12, which can act as new carriers for NMNPs. In this case, the Ag NPs are loaded onto the SEP nanowire assembly with a narrow size distribution from 5 to 20 nm in diameter; the average size is approximately 10 nm. The Ag NPs on the nanowire assemblies are well stabilized and the over agglomeration of Ag NPs is avoided owing to the existence of well-arranged polyoxometalate (POM) units in the SEP assembly and the hydrophobic surfactant on the surface of the nanowire assembly. Furthermore, the loading amount of the Ag NPs can be adjusted by controlling the concentration of the AgNO3 aqueous solution. The resultant Ag/CTAB-PW12 composite materials exhibit high activity and good stability for the catalytic reduction of 4-nitrophenol (4-NP) with NaBH4 in isopropanol/H2O solution. The NMNPs-loaded SEP nanoassembly may represent a new composite catalyst system for application in NM-based catalysis.

A new cationic triazole-based metal-organic framework encapsulating Keggin-type polyoxometalates, with the molecular formula [Co(BBPTZ)3][HPMo12O40]⋅24 H2O [compound 1; BBPTZ = 4,4'-bis(1,2,4-triazol-1-ylmethyl)biphenyl] is hydrothermally synthesized and characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, powder X-ray diffraction, and single-crystal X-ray diffraction. The structure of compound 1 contains a non-interpenetrated 3D CdSO4 (cds)-type framework with two types of channels that are interconnected with each other; straight channels that are occupied by the Keggin-type POM anions, and wavelike channels that contain lattice water molecules. The catalytic activity of compound 1 in the oxidative desulfurization reaction indicates that it is not only an effective and size-selective heterogeneous catalyst, but it also exhibits distinct structural stability in the catalytic reaction system.

Investigation into a hydrothermal reaction system with transition-metal (TM) ions, 1,4-bis(1,2,4-triazol-1-lmethyl)benzene (BBTZ) and various charge-tunable Keggin-type polyoxometalates (POMs) led to the preparation of four new entangled coordination networks, [Co(II) (HBBTZ)(BBTZ)2.5 ][PMo12 O40 ] (1), [Cu(I) (BBTZ)]5 [BW12 O40 ]⋅H2 O (2), [Cu(II) (BBTZ)]3 [AsW(V) 3 W(VI) 9 O40 ]⋅10 H2 O (3), and [Cu(II) 5 (BBTZ)7 (H2 O)6 ][P2 W22 Cu2 O77 (OH)2 ]⋅6 H2 O (4). All compounds were characterized by using elemental analysis, IR spectroscopy, thermogravimetric analysis, powder X-ray diffraction, and single-crystal X-ray diffraction. The mixed valence of W centers in compound 3 was further confirmed by using XPS spectroscopy and bond-valence sum calculations. In the structural analysis, the entangled networks of 1-4 demonstrate zipper-closing packing, 3D polythreading, 3D polycatenation, and 3D self-penetration, respectively. Moreover, with the enhancement of POM negative charges and the use of different TM types, the number of nodes in the coordination networks of 1-4 increased and the basic metal-organic building motifs changed from a 1D zipper-type chain (in 1) to a 2D pseudorotaxane layer (in 2) to a 3D diamond-like framework (in 3) and finally to a 3D self-penetrating framework (in 4). The photocatalytic properties of compounds 1-4 for the degradation of methylene blue under UV light were also investigated; all compounds showed good catalytic activity and the photocatalytic activity order of Keggin-type species was initially found to be {XMo12 O40 }{XW12 O40 }{XW12-n TMn O40 }.

The introduction of hydrogen peroxide, dl-mandelic acid (H2Mal), and acetate buffer into a reaction system containing zirconium(IV) ions and various trivacant polyoxometalates (POMs) led to the isolation of a series of new tetranuclear zirconium-substituted POMs modified by different O-donor ligands: Na4(NH4)14[Zr4(μ3-O)2(μ-O2)2(OAc)2(P2W16O59)2]·51H2O (1), (NH4)16[Zr4(μ3-O)2(Mal)2(H2O)2(P2W16O59)2]·14H2O (2), and Na7(NH4)5[{Zr4(OH)6(OAc)2}(SiW10O37)2]·20H2O(3) (3). All three compounds were characterized by elemental analyses, IR spectra, thermogravimetric (TG) analysis and single-crystal X-ray diffraction structural analyses. Compounds 1 and 2 possess similar sandwich-type polyoxoanion structures built from a tetranuclear Zr cluster and two [P2W16O59]12– building blocks, but they differ in the modifying ligands on the {Zr4} clusters, which are peroxido and mandelato for 1 and 2, respectively. The polyoxoanion of 3 contains a different tetranuclear Zr cluster, which is further sandwiched by two [α-SiW10O37]10– moieties and decorated by two acetato ligands. The catalytic activities of 1–3 were evaluated on the basis of a catalytic oxidation reaction of the peroxidase substrate 3,3′,5,5′-tetramethylbenzidine (TMB) by H2O2. Compound 1 exhibits the best catalytic activity, which suggests a new peroxidase-like catalyst for the colorimetric detection of H2O2 with a linear detection range from 100 to 1000 μM (r = 0.997) and a detection limit of 100 μM.

Nickel cobaltite, a low cost and an environmentally friendly supercapacitive material, is deposited as a thin nanostructure of 3–5 nm nanocrystals into carbon aerogels, a mesoporous host template of high specific surface areas and high electric conductivities, with a two-step wet chemistry process. This nickel cobaltite/carbon aerogel composite shows ultrahigh specific capacitances of around 1700 F g−1 at a scan rate of 25 mV s−1 within a potential window of −0.05 to 0.5 V in 1 M NaOH solutions. The composite also possesses an excellent high rate capability manifested by maintaining specific capacitances above 800 F g−1 at a high scan rate of 500 mV s−1, and an outstanding cycling stability demonstrated by a negligible 2.4% decay in specific capacitances after 2000 cycles. The success is attributable to the fuller utilization of nickel cobaltite for pseudocapacitance generation, made possible by the composite structure enabling well exposed nickel cobaltite to the electrolyte and easy transport of charge carriers, ions, and electrons, within the composite electrode.

A rationally designed oxygen evolution reaction (OER) catalyst with advanced structural and compositional superiority is highly desirable to optimize electrocatalytic performance. Prussian blue analogues (PBAs) with adjustable element compositions and accessible porous structures represent a promising precursor for the preparation of OER catalysts. Herein, oxygen-doped nickel iron phosphide nanocube arrays (Ni2 P/(NiFe)2 P(O) NAs) grown on Ni foam is rationally designed and fabricated from PBAs. The porous structure and the synergistic effect of Ni and Fe enable superior electrocatalytic performance and stability toward the OER in alkaline electrolytes. Density functional theory calculations reveal that Fe-incorporated Ni2 P can generate new active sites on the Fe atoms, and the energy barriers of the intermediates and products are decreased efficiently in the presence of surface doped oxygen, both processes are crucial factors for enhanced catalytic performances. In 1 m KOH, the Ni2 P/(NiFe)2 P(O) NAs afford current densities of 10 and 800 mA cm-2 at overpotentials of 150 and 530 mV, respectively, which outperform the commercial noble metal IrO2 . Ni2 P/(NiFe)2 P(O) NAs also have long-term stability over 100 h at a high current density. The present approach may provide a new avenue for the controlled assembly of nanoarrays for energy storage and conversion applications.

A novel organic-inorganic hybrid compound {[Cu (2, 2'-bpy)(2)](2)Mo8O26} has been hydrothermally Synthesized and structurally characterized by single-crystal X-ray diffraction. The compound crystallizes in the orthorhombic space group, Pna2(1), with a=2.4164 (5), b=1.8281 (4), c=1.1877 (2) nm, V=5.247(2) nm(3), Z=4, and final R-1=0.0331, wR(2)=0.0727. The structure consists of discrete {[Cu(2,2'-bpy)(2)](2)Mo8O26} clusters, constructed from a beta -octamolybdate subunit[Mo8O26](4-) covalently bonded to two [Cu(2,2'-bpy)(2)](2+) coordination complex cations via bridging oxo groups. In addition, the spectroscopic properties and thermal behavior of this compound have been investigated by spectroscopic techniques (UV-vis, IR, Raman and EPR spectra) and TG analysis.

Ultrathin multilayer films of a rare-earth-containing polyoxometalate Na-9[Eu(W5O18)(2)] (EW) and Poly (allyamine hydrochloride) (PAH) have been prepared by layer-by-layer self-assembly from dilute aqueous solutions. The fabrication process of the EW/PAH multilayer films was followed by UV-vis spectroscopy and ellipsometry, which show that the deposition process is linear and highly reproducible from layer to layer. An average EW/PAH bilayer thickness of ca. 2.1 nm was determine,by ellipsometry. In addition, the scanning electron microscopy (SEM) image of the EW/PAH film indicates that the film sufface is relatively uniform and smooth. The photoluminescent properties of these films were also investigated by fluoresence spectroscopy.

With 2 figures and 2 tables Abstract In this study, we report the mapping of the Rf locus in soybean by microsatellite simple sequence repeat (SSR) genetic markers. A cross was made between cytoplasmic male sterility (CMS) line JLCMS82A and restorer line JIHUI 1 based on the DNA polymorphisms revealed by 109 SSR markers. A F2 population derived from a single F1 plant containing 103 individuals was used for mapping the Rf locus. The Rf gene of JIHUI 1 gametophytically restores male fertility to JLCMS82A. Fertile and semi-fertile DNA bulks and parental DNAs were screened with 219 SSR markers, and Satt215 which was previously mapped to soybean LG J, was found linked to the Rf gene. Five additional polymorphic SSR markers from LG J were used for analysis and a regional linkage map around the Rf locus was established. SSR markers, Sctt011 and Satt547, flanked the Rf locus at 3.6 cM and 5.4 cM, respectively. The availability of these SSR markers will facilitate the selection of restorer lines in hybrid soybean breeding.

Two isostructural compounds, {[Cu2(DF)2H2O]2SiW12O40}·2H2O (1) and {[Cu2(DF)2H2O]2GeMo12O40}·2H2O (2) (DF = 4,5-diazafluoren-9-one), were synthesized and characterized by routine methods and single-crystal X-ray diffraction. In the compounds, each Keggin cluster links five copper dimers [Cu2(DF)2H2O]2+ in an unusual asymmetrical pentacoordination mode to form 3D networks with left- and right-handed helical chains. Notably, by comparing 1 and 2 with other helical compounds with Keggin clusters as connectors, we found that the pitches of those compounds are mainly dominated by the coordination modes of the Keggin clusters, suggesting that the Keggin clusters are pitch-tunable synthons. Furthermore, the luminescent and electrochemical properties of the title compound were studied. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

Employing a “one-pot” synthesis strategy, the reaction of Na2WO4·2H2O, Na2HAsO4·7H2O, FeCl3·6H2O, various Ln3+ ions, and hexamethylenetetramine (HMTA) in aqueous solutions with pH values ranging from 5.5 to 6.5 results in the isolation of polytungstoarsenate-based iron aggregates, -K8Na14[HMTA]4[(FeIII3FeII0.25(OH)3)(AsO4)(AsW9O34)]4·24H2O (1) (HMTA = hexamethylenetetraamine). The polyoxoanion of 1 contains a mixed-valent {FeIII12FeII(μ3-OH)12(μ4-AsO4)4} cluster surrounded by four [B-α-AsW9O34]9− units. It is the first polytungstatoarsenate-based mixed-valent {FeIII12FeII} aggregate and the largest iron cluster based on [AsW9O34]9− ligands. The compound was characterized by elemental analyses, IR, UV/Vis absorption, and diffuse-reflectance UV/Vis spectroscopy, TG analyses, XRPD, XPS and gel-filtration chromatography. The electrochemical and electrocatalytical properties were also investigated. Crystal data for 1, orthorhombic, Fddd, a = 28.156(6) A, b = 36.003(7) A, c = 42.126(8) A, α = 90°, β = 90°, γ = 90°, Z = 8.

The reaction of sandwich-type polyanion [Mn4Si2W18O68(H2O)2]12–, ceric sulfate, and potassium citrate in an acidic aqueous solution led to the isolation of a new compound K4Na2[{Ce(H2O)7}2Mn4Si2W18O68(H2O)2]·21.5H2O (1), which crystallizes in the space group P212121 with a = 12.040(2) A, b = 26.094(5) A, c = 30.043(6) A, V = 9439(3) A3, Z = 4, and flack parameter x = 0.63(1). X-ray diffraction analysis reveals that 1 consists of novel chiral ladder-like chains based on sandwich-type polyanions and lanthanide cations, which are further connected into a three-dimensional open framework by potassium cations.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

The title compound is hydrothermally synthesized from a mixture of Na2WO4, CoCl2, and en in diluted HCl (autoclave, pH 8.5, 100 °C, 108 h, 8% yield).

K8Na10{ [MnIV2MnIII6Mn II4(μ3-O)6 (μ-OH)4(H2O)2 (CO3)6] [B-β-SiW6O26] 2}·30H2O is synthesized from an aqueous mixture of K8[β2-SiW11O39], MnCl2, NaCl, 2,3-pyrazinedicarboxylic acid, and K2CO3 (pH 10.2, 50 °C, 5 h, 38% yield).

The structures of the new polyoxomolybdatophosphates (IV) (monoclinic, space group P21/n, Z = 2) and (V) (monoclinic, C2/c, Z = 4) are determined by single crystal XRD.

Employing a “one-pot” synthesis strategy, the reaction of Na2WO4·2H2O, Na2HAsO4·7H2O, FeCl3·6H2O, various Ln3+ ions, and hexamethylenetetramine (HMTA) in aqueous solutions with pH values ranging from 5.5 to 6.5 results in the isolation of polytungstoarsenate-based iron aggregates, -K8Na14[HMTA]4[(FeIII3FeII0.25(OH)3)(AsO4)(AsW9O34)]4·24H2O (1) (HMTA = hexamethylenetetraamine). The polyoxoanion of 1 contains a mixed-valent {FeIII12FeII(μ3-OH)12(μ4-AsO4)4} cluster surrounded by four [B-α-AsW9O34]9− units. It is the first polytungstatoarsenate-based mixed-valent {FeIII12FeII} aggregate and the largest iron cluster based on [AsW9O34]9− ligands. The compound was characterized by elemental analyses, IR, UV/Vis absorption, and diffuse-reflectance UV/Vis spectroscopy, TG analyses, XRPD, XPS and gel-filtration chromatography. The electrochemical and electrocatalytical properties were also investigated. Crystal data for 1, orthorhombic, Fddd, a = 28.156(6) A, b = 36.003(7) A, c = 42.126(8) A, α = 90°, β = 90°, γ = 90°, Z = 8.

The introduction of hexavacant Dawson-type precursor K(12)[H(2)P(2)W(12)O(48)] x 24 H(2)O into a HOAc/NaOAc (OAc(-) = acetate) buffer system containing (NH(4))(2)[Ce(IV)(NO(3))(6)] and Mn(II)(OAc)(2) x 4 H(2)O led to the isolation of a new compound, Na(20)[Ce(IV)(3)Mn(IV)(2)O(6)(OAc)(6)(H(2)O)(9)](2)[Mn(III)(2)P(2)W(16)O(60)](3) x 21 H(2)O (1). Compound 1 contains unusual triple-Dawson-type polyoxoanions [Mn(III)(2)P(2)W(16)O(60)](3)(24-) and bipyramid-like 3d-4f heterometallic clusters [Ce(IV)(3)Mn(IV)(2)O(6)(OAc)(6)(H(2)O)(9)](2+), which are arranged in a 3-D supramolecular assembly with 1-D channels. The Na(+) cations and solvent water molecules reside in the channels. Crystal data for 1 are as follows: hexagonal, P6(3)/mcm (No. 193), a = 24.959(4) A, c = 26.923(5) A, gamma = 120 degrees, V = 14525(4) A(3), and Z = 2. The electrochemical and electrocatalytic properties of compound 1 have been investigated.

The reaction between K12[H2P2W12O48] and CuCl2 in a NaCl aqueous solution assisted with organoamines (1,2-ethylenediamine (en), 1,6-hexamethylene diamine (hn), or both) leads to the isolation of three compounds: K4Na10[α1-CuP2W17O60(OH)]2·∼58H2O (1), Na2[H2en][H2hn]0.5[Cu(en)2]4.5[α1-CuP2W17O60(OH)]2·∼43H2O (2), and Na3[H2hn]2.5[α1-P2W17O60Cu(OH)2]·∼14H2O (3). The polyoxoanion [α1-CuP2W17O60(OH)]214− in 1 and 2 exhibits a double-Dawson-type polyoxoanion that consists of two α1-type mono-Cu-substituted Wells—Dawson anions, which can be synthesized by both the conventional aqueous solution method and the hydrothermal technique. Furthermore, the double-Dawson-type polyoxoanions in 2 are linked by the [Cu(en)2]2+ bridges to form 2-D networks, which are further packed into a 3-D supramolecular porous framework via extensive hydrogen bonding interactions, exhibiting two types of tunnels (A and B). Compound 3 possesses a 3-D supramolecular framework with 1-D tunnels constructed from the α1-type mono-Cu-substitut...

The first {P2W12}-based trimeric polyoxotungstates encapsulating various “guest” transition-metal and alkali-metal ions have been reported, exhibiting potentially aqua-ligand-induced capability of “trapping” metal ions.

The reaction of sandwich-type polyanion [Mn4Si2W18O68(H2O)2]12–, ceric sulfate, and potassium citrate in an acidic aqueous solution led to the isolation of a new compound K4Na2[{Ce(H2O)7}2Mn4Si2W18O68(H2O)2]·21.5H2O (1), which crystallizes in the space group P212121 with a = 12.040(2) A, b = 26.094(5) A, c = 30.043(6) A, V = 9439(3) A3, Z = 4, and flack parameter x = 0.63(1). X-ray diffraction analysis reveals that 1 consists of novel chiral ladder-like chains based on sandwich-type polyanions and lanthanide cations, which are further connected into a three-dimensional open framework by potassium cations.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

Two novel complexes based on 2-aminopyridine and polyoxometalates (POMs) formulated as (C5H7N2)6-[PMo11VMoVIO40(VIVO)4]·H2O (1) and (C5H7N2)16[P2W18O61.5]2 (2) were hydrothermally synthesized and structurally characterized by elemental analysis, ICP, IR, UV-Vis, TG, ESR and single crystal X-ray diffraction methods. Complex 1 consists of a novel tetra-capped Keggin POMs, [PMo11VMoVIO40(VIVO)4]6− in which four [VIVO5] square pyramids cap the equatorial positions of Keggin core [PMo11VMoVIO40]14−, linked together with six protonated 2-aminopyridine via hydrogen bonding interactions. Dawson and lacunary Dawson POMs, [P2W18O62]6− and [P2W17O61]10− coexist in complex 2, they link together with sixteen protonated 2-aminopyridine via hydrogen bonding interactions. Complex 2 exhibits photochromic property.

Novel Co-Cu complex nanorods with diameters of 100-200 nm and nanorings with a ring-diameter of 80 nm were synthesized via a microemulsion method at room temperature. Using this method, the addition of Co(NH3)(3+)6 to aqueous solutions of Cu(ii) in excessive carbonate promotes the assembly of a new highly charged carbonato-copper(ii) anion, [Cu4(OH)(CO3)8]9-.

α-Al2O3 nanowires and nanobelts have been successfully synthesized from Al pieces and SiO2 nanoparticles at 1200 °C and 1150 °C, respectively, in a flowing Ar atmosphere. The α-Al2O3 nanowires are uniform with diameters of 20−70 nm and lengths of 15−25 μm, and the nanobelts are several to tens of micrometers long, with width of 0.1−1 μm and thickness of 10−50 nm. The growth of the nanowires is controlled by a vapor−liquid−solid (VLS) growth mechanism, while the growth of the nanobelts may be due to a vapor−solid (VS) process. Infrared spectra of these nanostructures are different from that of the bulk α-Al2O3. Photoluminescence (PL) measurements under excitation at about 255 nm show that the nanowires and nanobelts have emission peaks at 394 and 392 nm, respectively. On the basis of the discussion of the thermal annealing in different atmospheres such as O2 and H2 on the behaviors of the PL spectra, we suggest that optical transitions in oxygen-related defects, F+ (oxygen vacancy with one electron) center...