Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 20
Filter
Add more filters










Publication year range
1.
J Hazard Mater ; 430: 128351, 2022 May 15.
Article in English | MEDLINE | ID: mdl-35149487

ABSTRACT

The development of high-efficient and cost-effective electrocatalysts is crucial to remove nitrate pollutant in wastewater. Herein, we design and prepare mesoporous Co-doped Cu2(OH)2CO3 malachite nanosheets as an electrocatalyst toward highly efficient nitrate reduction using a facile CO2 bubble-assisted coprecipitation synthesis. The electrocatalytic performance is subject to the Co/Cu ratio of this malachite. Remarkably, compared with the pristine monometal Cu or Co-based electrocatalyst, the optimal electrocatalyst, 0.3Co@Cu2(OH)2CO3, displays fast and highly efficient removal capacity of nitrate with an impressive high total nitrogen (TN) removal of 8628.99 mg N g-1CoCu (398.79 mg N gcat-1 h-1), N2 selectivity of 97.11% as well as negligible nitrite product at 100 mg L-1 NO3--N and 2000 mg L-1 Cl- neutral electrolyte. Above all, high total nitrogen removal efficiency (81.92%) and chemical oxygen demand (73.74%) in actual wastewater. Its excellent electrocatalytic performance is achieved by regulating the electronic structure and the adsorption/desorption of the intermediate. This study discovers a new type of electrode materials for nitrate removal in wastewater.

2.
Chemistry ; 27(28): 7731-7737, 2021 May 17.
Article in English | MEDLINE | ID: mdl-33792092

ABSTRACT

Transition-metal phosphates have been widely applied as promising candidates for electrochemical energy storage and conversion. In this study, we report a simple method to prepare a N, F co-doped mesoporous cobalt phosphate with rich-oxygen vacancies by in-situ pyrolysis of a Co-phosphate precursor with NH4 + cations and F- anions. Due to this heteroatom doping, it could achieve a current density of 10 mA/cm2 at lower overpotential of 276 mV and smaller Tafel slope of 57.11 mV dec-1 on glassy carbon. Moreover, it could keep 92 % of initial current density for 35 h, indicating it has an excellent stability and durability. Furthermore, the optimal material applied in supercapacitor displays specific capacitance of 206.3 F g-1 at 1 A ⋅ g-1 and maintains cycling stability with 80 % after 3000 cycles. The excellent electrochemical properties should be attributed to N, F co-doping into this Co-based phosphate, which effectively modulates its electronic structure. In addition, its amorphous structure provides more active sites; moreover, its mesoporous structure should be beneficial to mass transfer and electrolyte diffusion.

3.
ChemSusChem ; 13(10): 2564-2570, 2020 May 22.
Article in English | MEDLINE | ID: mdl-32196953

ABSTRACT

It remains a challenge to rational design of a new metal-organic framework (MOF) as highly efficient direct electrocatalysts for the oxygen evolution reaction (OER). Herein, we developed a simple and effective method to explore a new pillared-layered MOF with syringic acid as a promising OER electrocatalyst. The isostructural mono-, heterobimetallic MOF and N,S co-doped MOF by mixing thiourea were quickly synthesized in a high yield under solvothermal condition. Moreover, the optimized N,S co-doped MOF exhibits the lowest overpotential of 254 mV at 10 mA cm-2 on a glass carbon electrode and a small Tafel slope of 50 mV dec-1 , especially, this catalyst also possesses long-term electrochemical durability for at least 16 h. According to the characterization, the incorporation of N and S atoms into this heterobimetallic CoFe-based MOF could modify its pore structure, tune the electronic structure, accordingly, improve the mass and electron transportation, and facilitate the formation of active species, as a consequence, the improved activity of this new N,S co-doped MOF for OER should be mainly be ascribed to higher electrochemical activation toward the active species via in situ surface modification during the OER process.

4.
Nanoscale ; 11(14): 6719-6726, 2019 Apr 04.
Article in English | MEDLINE | ID: mdl-30900701

ABSTRACT

The development of nontoxic and stable all-inorganic perovskite nanocrystals (NCs) represents a major challenge to unlock widely practical applications in photoelectric fields. It is an effective strategy to discover nontoxic metal perovskite nanocrystals (NCs) with excellent optical properties. In addition, it has been proved that alkali metals such as rubidium (Rb) and potassium (K) have a good influence on improving the optical performance of perovskites. Hence, we reported new lead-free perovskite Rb7Bi3Cl16 single crystals, which displayed a zero-dimensional cluster structure and were composed of two kinds of octahedra with different distortions. At the same time, we synthesized its NCs, which showed a blue emission at 437 nm with a PLQY of 28.43% and presented a good optical and moisture stability for one month. The excellent moisture-stability might be attributed to their much higher ratio of Rb atoms and the ideal [BiCl6]3- octahedra on the surface, which are beneficial to form an inorganic BiOCl shell to protect the Rb7Bi3Cl16 NCs from moisture attack.

5.
Acta Crystallogr C Struct Chem ; 74(Pt 12): 1744-1749, 2018 12 01.
Article in English | MEDLINE | ID: mdl-30516160

ABSTRACT

Organic-inorganic hybrid lead-based perovskite crystal materials have been widely studied due to their excellent optical-electronic properties. However, the toxicity of lead limits their widespread use. Here, a lead-free perovskite-type compound, tetrakis(1,2,3-trimethylimidazolium) di-µ3-iodido-tetra-µ2-iodido-decaiodidotetrabismuth(III), (C6H11N2)4[Bi4I16], has been successfully synthesized by a simple solvothermal method. It exhibits a zero-dimensional (0D) tetrameric structure, including edge-sharing [Bi4I16]4- distorted octahedra. The band gap of 2.0 eV is close to that of (NH4)3[Bi2I9]. Degradation ability measurements were performed to examine the potential application of this material as an alternative for waste-water treatment.

6.
Acta Crystallogr C Struct Chem ; 74(Pt 10): 1146-1152, 2018 10 01.
Article in English | MEDLINE | ID: mdl-30284981

ABSTRACT

Germanophosphates, as a young class of metal phosphates, have been less reported but might possess more diverse structural types and potential applications. Here, two one-dimensional (1D) alkali-metal germanophosphates (GePOs), namely, hydrogen hexakis(µ-hydrogen phosphato)digermaniumtrirubidium, HRb3Ge2(HPO4)6 (1), and caesium bis(µ-hydrogen phosphato)(µ-hydroxido)germanium, CsGe(HPO4)2(OH) (2), have been prepared by the solvothermal method. Compound 1 shows 1D [Ge(HPO4)6]∞ chains along the c axis formed by GeO6 octahedra and PO4 tetrahedra, with Rb+ cations dissociated between the chains. Compound 2 also exhibits 1D [Ge(HPO4)4(OH)2]∞ chains constructed from adjacent Ge(HPO4)4(OH)2 octahedra, with Cs+ cations dissociated between the chains. XRD, TGA, IR and UV-Vis-NIR absorption spectra are presented and discussed for both compounds.

7.
Dalton Trans ; 47(41): 14497-14502, 2018 Oct 23.
Article in English | MEDLINE | ID: mdl-30280743

ABSTRACT

The main commercial infrared nonlinear optical (IR NLO) crystals, typically, AgGaS2, have some inherent disadvantages, for example, low laser damage threshold (LDT) or relatively poor stability, which limit their wide application. Here, we discover two new IR optical perovskites based on 1,4-diazabicyclo[2,2,2]octane, namely, (H2dabco)(PbCl3)2 (1) and (H2dabco)(H2PbBr6)·H2O (2). 1 and 2 crystallize in the noncentrosymmetric space groups P43212 and P63mc, respectively, displaying a broad transparent range with high transmission. Particularly, compound 2 exhibits a moderate SHG response of 1.8 times that of KH2PO4 (KDP) at 1064 nm with a high laser-induced damage threshold of 328.8 MW cm-2, indicating that it is a new promising NLO material.

8.
Dalton Trans ; 47(16): 5764-5770, 2018 Apr 24.
Article in English | MEDLINE | ID: mdl-29637203

ABSTRACT

Two new alkali boroselenites RbSe3B2O9(OH) and CsSe3B2O9(OH) have been synthesized by traditional solid-state reactions. Single-crystal X-ray diffraction study indicated that they are isostructural and adopt a new type of structure, which crystallizes in the noncentrosymmetric space group P212121. Optical diffuse reflectance spectrum studies emphasized that both are indirect optical transitions with values of 3.79 and 4.17 eV for RbSe3B2O9(OH) and CsSe3B2O9(OH), respectively. Optical analysis revealed a broad transparency window in the 0.3-8.5 µm region for both compounds. In addition, RbSe3B2O9(OH) featured a relatively weak second-harmonic-generation response, and for CsSe3B2O9(OH), the response is 0.8-times that of KH2PO4. Theoretical calculations of band structure, density of state, and linear and nonlinear optical properties were also performed to get insight into the relationships between electronic structures and their optical properties.

9.
Dalton Trans ; 46(29): 9339-9343, 2017 Jul 25.
Article in English | MEDLINE | ID: mdl-28671214

ABSTRACT

Herein, unprecedented NLO-brominated tin hypophosphites, namely [Sn2(H2PO2)3]Br, were discovered via a facile surfactant-induced method, which displayed a moderate powder SHG intensity (3.0 × KDP) in type - I phase matching behavior. This complex has high chemical and thermal stability at room temperature. DFT calculations and SHG coefficient analyses revealed that the alignment of the SHG-active-units SnO3 trigonal pyramids and Br- anions in its structure mainly contribute to the macroscopical SHG behaviors.

10.
J Colloid Interface Sci ; 475: 192-195, 2016 Aug 01.
Article in English | MEDLINE | ID: mdl-27175829

ABSTRACT

Tin phosphite nanosheets were synthesized by a facile exfoliation method. SnHPO3 nanosheets with a thickness of ∼2.6nm readily form a stable colloidal suspension in ethanol using ultrasonic method. Structures and optical properties of the obtained nanosheets were investigated. The prepared SnHPO3 nanosheets exhibit an obvious blue-shift in UV absorbance compared with bulk SnHPO3 crystal materials. Moreover, the piezoelectric coefficients of SnHPO3 monolayer were calculated based on density functional theory, which are larger than that of h-BN monolayer, indicating this material could be a good candidate for designing electro-optical nano-devices.

11.
Angew Chem Int Ed Engl ; 54(12): 3679-82, 2015 Mar 16.
Article in English | MEDLINE | ID: mdl-25630286

ABSTRACT

A new SHG material, namely, Pb2(BO3)(NO3), which contains parallel π-conjugated nitrate and borate anions, was obtained through a facile hydrothermal reaction by using Pb(NO3)2 and Mg(BO2)2⋅H2O as starting materials. Its structure contains honeycomb [Pb2(BO3)]∞ layers with noncoordination [NO3](-) anions located at the interlayer space. Pb2(BO3)(NO3) shows a remarkable strong SHG response of approximately 9.0 times that of potassium dihydrogen phosphate (KDP) and the material is also phase-matchable. The large SHG coefficient of Pb2(BO3)(NO3) arises from the synergistic effect of the stereoactive lone pairs on Pb(2+) cations and parallel alignment of π-conjugated BO3 and NO3 units. Based on its unique properties, Pb2(BO3)(NO3) may have great potential as a high performance NLO material in photonic applications.

12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(8): 2047-50, 2013 Aug.
Article in Chinese | MEDLINE | ID: mdl-24159843

ABSTRACT

The measurement of nonuniform temperature and concentration distributions was investigated based on tunable diode laser absorption spectroscopy technology. Through direct scanning multiple absorption lines of H2O, two zones for temperature and concentration distribution were achieved by solving nonlinear equations by least-square fitting from numerical and experimental studies. The numerical results show that the calculated temperature and concentration have relative errors of 8.3% and 7.6% compared to the model, respectively. The calculating accuracy can be improved by increasing the number of absorption lines and reduction in unknown numbers. Compared with the thermocouple readings, the high and low temperatures have relative errors of 13.8% and 3.5% respectively. The numerical results are in agreement with the experimental results.

13.
Inorg Chem ; 52(15): 8979-86, 2013 Aug 05.
Article in English | MEDLINE | ID: mdl-23834222

ABSTRACT

Using lead metaborate as starting material, by only adjusting pH values of the reaction systems, a series of lead(II) borates were obtained in high yields. The new polar material, namely, Pb2B3O5.5(OH)2 (1), crystallizes in the noncentrosymmetric space group Pnn2 of the orthorhombic system. Its structure features a novel three-dimensional (3D) anionic network with large 14 member rings (MRs) tunnels composed of unique one-dimensional (1D) chains and dimeric B2O7 fragments, both of which are built up from solely BO4 tetrahedra, and the Pb(2+) cations are located at the above 14-MRs tunnels. The synergistic effect of the stereoactive lone-pairs on Pb(2+) cations in 1 produces a strong SHG response of ∼3× KDP (KH2PO4) which is type I phase-matchable. The first example of lead(II) borate nitrate, namely, [Pb3(B3O7)](NO3) (2), crystallizes in space group Pnma, and its structures features a 3D lead(II) borate cationic network structure in which (B3O7)(5-) anions are bridged by lead(II) cations, the nitrate anions are isolated, and located at the small voids of the cationic network. Thermal stability and optical properties as well as theoretical calculations based on density functional theory (DFT) methods were also performed.

14.
Inorg Chem ; 52(4): 1843-53, 2013 Feb 18.
Article in English | MEDLINE | ID: mdl-23388037

ABSTRACT

Four new layered silver(I) organoarsonates, namely, [Ag(3)(L(3))(CN)] (1) (H(2)L(3) = (PhAsO(2)H)(2)O), [Ag(3)(L(4))(CN)] (2) (H(2)L(4) = (2-NO(2)-C(6)H(4)-AsO(2)H)(2)O), [Ag(3)(HL(5))(H(2)L(5))] (3) (H(3)L(5) = 3-NO(2)-4-OH-C(6)H(3)-AsO(3)H(2)) and [Ag(2)(HL(5))] (4), were synthesized under solvothermal conditions. During the preparations of 1 and 2, condensation of organoarsonate ligands (H(2)L(1) = Ph-AsO(3)H(2); H(2)L(2) = 2-NO(2)-C(6)H(4)-AsO(3)H(2)) and the decomposition of acetonitrile molecules to cyanide anions occurred. Single crystals of H(2)L(4) ligand and compounds 1-4 were isolated, and their crystal structures have been determined by single crystal X-ray diffraction studies. In 1, the one-dimensional (1D) chains based on Ag(I) ions and {L(3)}(2-) anions are further interconnected by CN(-) into two-dimensional (2D) layers. In 2, adjacent Ag(I) ions within the silver(I) organoarsonate layer are further bridged by µ(4)-CN(-) anions with very short Ag···Ag contacts. In 3, the hexanuclear {Ag(6)O(12)} clusters are interconnected by bridging organoarsonate ligands into a silver(I) arsonate hybrid layer. In 4, the right-handed {Ag(4)O(4)} chains are further interconnected by organoarsonate ligands as well as additional Ag-O-Ag bridges into a novel silver(I) arsonate layer. Compounds 1 and 2 display red and orange-red emissions, respectively, which may be assigned to be an admixture of ligand-to-metal charge transfer (LMCT) and metal-centered (4d-5s/5p) transitions perturbed by Ag(I)···Ag(I) interactions. Upon cooling from room temperature to 10 K, compound 1 exhibits interesting temperature-dependent emissions.

15.
Zhonghua Zhong Liu Za Zhi ; 34(6): 477-80, 2012 Jun.
Article in Chinese | MEDLINE | ID: mdl-22967454

ABSTRACT

OBJECTIVE: To compare the results of application of Qu single abdominal aorta clamping for bloodless hepatectomy and Pringle hepatectomy in 118 cases of liver tumors. METHODS: The clinical data of 118 patients, including 59 patients undergoing Qu single abdominal aorta clamping for bloodless hepatectomy (Group QG) and 59 patients undergone Pringle first hepatic portal clamping hepatectomy (Group PG) since March 2009 in the Ningbo Tumor Hospital and Jiangxi Provincial Hospital were retrospectively reviewed. The changes of blood pressure, oxygen saturation, urine volume, intravenous fluid volume, amount of bleeding, time of abdominal aorta (or first hepatic portal) clamping, duration of operation and anesthesia, and other intraoperative indexes of the two groups were compared, and the changes of peritoneal drainage, blood tests, liver functions, etc. before operation and 1, 3, 7, 14 days after the hepatectomy in the two groups were also analyzed. RESULTS: After taking appropriate measures for intraoperative blood pressure control, only small fluctuations of blood pressure, which could be safely adjusted and controlled with stable vital signs, was observed in the group QG. The amount of intraoperative bleeding in the group QG was (96.25 ± 18.45) ml, significantly less than (536.25 ± 35.65) ml in the group PG (P < 0.05). In the group QG, both the duration of operation time [(227.58 ± 28.20) min] and duration of anesthesia [(249.48 ± 31.35) min] were significantly shorter than that [(261.46 ± 32.12) min and (286.58 ± 35.62) min, respectively] in the group PG (both P < 0.05). The postoperative liver dysfunction in the group QG was also milder than that in the group PG (P < 0.05). CONCLUSIONS: For liver tumor patients, Qu single abdominal aorta clamping for bloodless hepatectomy can basically achieve the goal of bloodless hepatectomy. This surgical operation is simple and safe, worthy of recommendation to skillful liver surgeons in hospitals there are some difficulties of blood supply.


Subject(s)
Carcinoma, Hepatocellular/surgery , Hepatectomy/methods , Liver Neoplasms/surgery , Adolescent , Adult , Alanine Transaminase/blood , Aorta, Abdominal , Aspartate Aminotransferases/blood , Blood Loss, Surgical , Blood Pressure , Carcinoma, Hepatocellular/blood , Constriction , Female , Hemangioma, Cavernous/blood , Hemangioma, Cavernous/surgery , Humans , Liver Neoplasms/blood , Male , Middle Aged , Operative Time , Portal Vein , Retrospective Studies , Serum Albumin/metabolism , Young Adult
16.
Opt Express ; 18(2): 1296-301, 2010 Jan 18.
Article in English | MEDLINE | ID: mdl-20173955

ABSTRACT

We report a quantum dot sensitized solar cell (QDSSC) with a thioglycolic acid (TGA) capped CdSe quantum dot (QD) sensitized ZnO nanorod photoanode. As revealed by UV-Vis absorption spectrum and transmission electron microscopy, the quantum dots can be effectively adsorbed onto ZnO nanorods. By studying the emission decay, the quenching of the CdSe QDs by ZnO nanorod was verified, and an electron transfer (from QD to ZnO) rate constant of 1 x 10(8) s(-1) was obtained. The efficiency of the as-prepared QDSSC was 0.66% and an incident power conversion efficiency of 22% at 400 nm was achieved.


Subject(s)
Cadmium Compounds/chemistry , Electric Power Supplies , Fluorescent Dyes/chemistry , Nanostructures/chemistry , Quantum Dots , Selenium Compounds/chemistry , Solar Energy , Zinc Oxide/chemistry , Cadmium Compounds/radiation effects , Electrodes , Equipment Design , Equipment Failure Analysis , Ligands , Light , Nanostructures/radiation effects , Selenium Compounds/radiation effects , Zinc Oxide/radiation effects
17.
Chemistry ; 11(5): 1417-24, 2005 Feb 18.
Article in English | MEDLINE | ID: mdl-15651021

ABSTRACT

Hydrothermal reactions of the lanthanide chlorides with MeN(CH2CO2H)(CH2PO3H2), (H3L1) (or Me2NCH2PO3H2, H2L2) and sodium oxalate lead to seven new lanthanide oxalate phosphonate hybrids with three types of 3D network structures, namely, [Ln(C2O4){MeNH(CH2CO2)(CH2PO3H)}]0.5 H2O (Ln=Nd: 1; Eu: 2; Gd: 3), [Ln4(C2O4)5(Me2NHCH2PO3)2(H2O)4]2 H2O (Ln=La: 4, Nd: 5), [Ln3(C2O4)4(Me2NHCH2PO3)(H2O)6]6 H2O (Gd: 6, Er: 7). Their structures have been established by X-ray single-crystal diffraction. Complexes 1-3 are isostructural and feature a 3D network formed by the interconnection of 3D network of {Ln(H2L1)}2+ with 1D chains of {Ln(C2O4)}+. Complexes 4 and 5 are isostructural and feature a complex 3D network built from 3D network of lanthanide oxalate and {Ln4(HL2)2} units. The isostructural 6 and 7 form another type of 3D network composed of porous lanthanide-oxalate network inserted by 1D chains of lanthanide-oxalate phosphonate. Compounds 1, 5 and 7 are luminescent materials in the near IR region. Compounds 3 and 6 exhibit a broad blue fluorescent emission band at 451 and 467 nm, respectively. Compound 2 displays very strong and sharp emission bands at 592, 616 and 699 nm with a long luminescent lifetime of 1.13 ms.

18.
Inorg Chem ; 43(18): 5630-4, 2004 Sep 06.
Article in English | MEDLINE | ID: mdl-15332814

ABSTRACT

Hydrothermal reactions of lanthanide metal salts with MeN(CH(2)CO(2)H)(CH(2)PO(3)H(2)) (H(3)L) and 5-sulfoisophthalic acid monosodium salt (NaH(2)BTS) lead to four isomorphous lanthanide carboxylate-phosphonate-sulfonate hybrids, namely, Ln(H(2)L)(HBTS)(H(2)O)(2).H(2)O (Ln = La (1), Pr (2), Nd (3), Gd (4)). Their structures have been established by X-ray single-crystal diffraction. The interconnection of the lanthanide(III) ions by carboxylate-phosphonate ligands results in a 1D double chain; these double chains are further bridged by bidentate bridging carboxylate-sulfonate ligands to form a <011> layer. The luminescent properties of compounds 3 and 4 have also been studied.


Subject(s)
Lanthanoid Series Elements/chemistry , Luminescent Measurements , Organometallic Compounds , Organophosphonates/chemistry , Sulfur Compounds/chemistry , Alkanesulfonates/chemistry , Crystallography, X-Ray , Models, Chemical , Models, Molecular , Organometallic Compounds/chemical synthesis , Organometallic Compounds/chemistry
19.
Inorg Chem ; 43(6): 1964-8, 2004 Mar 22.
Article in English | MEDLINE | ID: mdl-15018517

ABSTRACT

Hydrothermal reaction of H(3)PO(3), CH(3)NH(2), zinc(II) acetate, 4,4'-bipyridine (bipy), and (NH(4))(6)Mo(7)O(24).4H(2)O at 180 degrees C led to a novel organic-inorganic layered hybrid, [CH(3)NH(3)][H(2)bipy][Zn(4)(bipy)(3)(H(2)O)(2)Mo(V)(8)Mo(VI)O(36)(PO(4))].4H(2)O (1). Its structure was established by single-crystal X-ray diffraction. It crystallizes in the monoclinic space group P2(1)/c with cell parameters of a = 17.3032(2), b = 17.8113(3), and c = 23.4597 (4) A, beta = 106.410(1) degrees, V = 6935.6(2) A(3), and Z = 4. The structure of compound 1 features a novel 2D layer built from the 8e-reduced tetracapped Keggin [Zn(4)Mo(12)O(36)(PO(4))](3)(-) anions, which are further interconnected by bridging bipy ligands. The four zinc(II) ions are in tetrahedral, trigonal bipyramidal, and octahedral coordination geometries, respectively.

20.
Inorg Chem ; 42(6): 2136-40, 2003 Mar 24.
Article in English | MEDLINE | ID: mdl-12639152

ABSTRACT

The simultaneous desulfurization of 2-mercapto-5-methyl-1,3,4-thiadiazole with CuCl(2) x 2H(2)O via mutual diffusion in solvents results in the isolation of air-stable dark-green crystals of [Cu(H(4)C(3)N(2)S)Cl(2)](n) (approximately 65% yield). The structure is characterized by a unique one-dimensional copper chain bridged by diazine N-N single bonds rather than halogens, in sharp contrast with the halide bridging mode in conventional copper halide coordination polymers. Each Cu(II) ion shows a square planar coordination geometry featuring a strong Jahn-Teller distortion, as also supported by EPR data. The phase follows a Curie-Weiss paramagnetic behavior over 6-300 K. However, the intrachain antiferromagnetic interaction is evident (-2J = 21.1 cm(-1)). Such magnetic coupling is related to the interplay between the Cu(II)-d(x2-y2) and diazine N-N p-orbitals.

SELECTION OF CITATIONS
SEARCH DETAIL
...