Xi:Irritant;
1304-76-3Relevant articles and documents
Improved electrochemical properties of LiMn2O4 with the Bi and La co-doping for lithium-ion batteries
Han, Cheng-Gong,Zhu, Chunyu,Saito, Genki,Akiyama, Tomohiro
, p. 73315 - 73322 (2015)
A series of LiBixLaxMn2-2xO4 (x = 0, 0.002, 0.005, 0.010, 0.020) samples were synthesized by solution combustion synthesis in combination with calcination. The phase structure and morphology of the products were characterized by X-ray diffraction, scanning electron microscopy, and transition electron microscopy. The results demonstrated that a single-phase LiMn2O4 spinel structure was obtained for the LiBixLaxMn2-2xO4 (x = 0, 0.002, 0.005) samples, whereas impurities were observed for the LiBixLaxMn2-2xO4 (x = 0.010, 0.020) samples as a result of the doping limit. The electrochemical properties were investigated by galvanostatic charge-discharge cycling and cycling voltammetry in a voltage range of 3.2-4.4 V. The substitution of Mn3+ by equimolar Bi3+ and La3+ could significantly improve the structural stability and suppress the Jahn-Teller distortion, thereby resulting in improved electrochemical properties for the Bi and La co-doped samples in contrast with the pristine LiMn2O4 sample. In particular, the LiBi0.005La0.005Mn1.99O4 sample delivered a high initial discharge capacity of 130.2 mA h g-1 at 1C, and following 80 cycles, the capacity retention was as high as 95.0%. Moreover, it also presented the best rate capability among all the samples, in which a high discharge capacity of 98.3 mA h g-1 was still maintained at a high rate of 7C compared with that of 75.8 mA h g-1 for the pristine LiMn2O4 sample.
The preparation and characterization of composite bismuth tungsten oxide with enhanced visible light photocatalytic activity
Chen, Shifu,Tang, Wenming,Hu, Yingfei,Fu, Xianliang
, p. 7943 - 7950 (2013)
A composite photocatalyst (Bi3.84W0.16O 6.24-Bi2WO6) containing Bi, W and O elements was prepared by a facile hydrothermal method. Various characterization methods such as X-ray powder diffraction, UV-vis diffuse reflectance spectroscopy, scanning electron microscopy and transmission electron microscopy were employed to investigate the structure and optical properties. The activities of the samples were evaluated by the photocatalytic degradation of methylene blue under visible light irradiation. The results showed that when the pH of the precursor solution is 12.3, and a hydrothermal treatment at 140 °C for 20 h was used, the prepared sample shows the mixed phases of Bi3.84W 0.16O6.24 and Bi2WO6. The Bi 3.84W0.16O6.24-Bi2WO6 composite exhibited an enhanced photocatalytic activity compared with single Bi2WO6 or Bi3.84W0.16O 6.24. The rate constant of Bi3.84W0.16O 6.24-Bi2WO6 is about 5 times that of Bi 2WO6. It is proposed that the increased photocatalytic activity may be attributed to the formation of a heterojunction between Bi 3.84W0.16O6.24 and Bi2WO 6, which suppresses the recombination of photoexcited electron-hole pairs.
Mechanochemical destruction of decabromodiphenyl ether into visible light photocatalyst BiOBr
Zhang, Kunlun,Huang, Jun,Wang, Haizhu,Yu, Gang,Wang, Bin,Deng, Shubo,Kano, Junya,Zhang, Qiwu
, p. 14719 - 14724 (2014)
In the present study, mechanochemical (MC) treatment of polybrominated diphenyl ethers (PBDEs), a kind of emerging persistent organic pollutant (POPs), was performed using a high energy ball mill. With Bi2O3 as co-milling reagent, deca-BDE was effectively destroyed and no hazardous intermediates or organic products were observed in the MC reaction. Meanwhile, BiOBr, a promising visible light photocatalyst, was proved to be the final product which could be utilized in further steps. Neither excessive Bi 2O3 nor unreacted deca-BDE was left after the reaction as they were originally added at stoichiometric ratio for BiOBr formation. FITR and Raman analyses demonstrate the collapse of deca-BDE skeleton and the cleavage of C-Br bonds with the generation of inorganic carbon, revealing the mechanism of carbonization and debromination. The gaseous products at different reaction atmosphere were also analyzed, showing that mostly CO2 with a fraction of CO were released during the MC process. The reaction formula of deca-BDE and Bi2O3 was then proposed based on the identified final products. Besides, the photocatalytic activity of the generated BiOBr was evaluated using methyl orange as the model pollutant. A good degradation performance from BiOBr was achieved under both simulated sunlight and visible light irradiation, indicating the possibility for its further utilization. This journal is the Partner Organisations 2014.
TiO2-Bi2O3/(BiO)2CO3-reduced graphene oxide composite as an effective visible light photocatalyst for degradation of aqueous bisphenol A solutions
?erjav, Gregor,Djinovi?, Petar,Pintar, Albin
, p. 237 - 246 (2018)
TiO2 nanorods (T) were combined with a narrow band gap semiconductor β-Bi2O3 (B) to form a heterojunction, which makes it possible for TiO2 to become active as a photocatalyst also under visible light illumination. To further increase the photocatalytic activity of TiO2 + Bi2O3/(BiO)2CO3 (TB) composite, we used a hydrothermal procedure to link it with reduced graphene oxide (rGO). Structural, surface and electronic properties of the obtained catalysts were analyzed and correlated to their performance in photocatalytic oxidation of aqueous bisphenol A (BPA) solution conducted in a batch reactor under visible light illumination. XRD, FTIR, UV–vis DR spectroscopy and photocurrent measurements of visible light illuminated TB composite catalyst clearly showed that (i) β-Bi2O3 acts as a photosensitizer for TiO2 and (BiO)2CO3 present in the TB composite, (ii) holes (h+) are photo-generated in valence band (VB) of β-Bi2O3 and due to the β-Bi2O3/TiO2 heterojunction transferred into VB of TiO2, (iii) p-n junction between β-Bi2O3 and TiO2 allows the photo-generated electrons (e?) in the conduction band (CB) of β-Bi2O3 to transfer to TiO2, and (iv) p-n junction between β-Bi2O3 and (BiO)2CO3 allows the photo-generated electrons in the conduction band of β-Bi2O3 to transfer to (BiO)2CO3. This means that more charge carriers are available to participate in the catalytic visible-light triggered oxidation process for the degradation of organic pollutants dissolved in water. The highest photocurrent density was measured for multi-phase TBR (TB + rGO) composite, which indicates that visible-light generated charge carriers in TB composite are injected into the reduced graphene oxide. The latter acts as a web for charge carrier percolation and suppresses the recombination of electron-hole pairs, thus resulting in improved catalytic activity of TBR. The results of UV–vis DR spectroscopy and photocurrent density measurements were entirely in line with the results of photocatalytic oxidation of water dissolved bisphenol A (BPA) in batch reactor under visible light illumination.
Characterization and photocatalytic activity of Bi3TaO7 prepared by hydrothermal method
Luo, Bifu,Chen, Min,Zhang, Zhengyuan,Hong, Yuanzhi,Lv, Taotao,Shi, Weidong
, p. 203 - 212 (2017)
In this paper, Bi3TaO7 nanoparticles with visible light response have been prepared via a facile hydrothermal route and solid-state reaction. The photocatalytic performance of as-prepared samples was evaluated by the degradation of Tetracycline hydrochloride (TC). It was observed that the sample obtained by hydrothermal method showed an enhanced photocatalytic activity in contrast to the sample prepared by solid-state method. This could be ascribed to the efficient separation of photogenerated electrons and holes in the sample prepared via hydrothermal process, which is certified by the photoluminescence spectroscopy (PL) and transient photocurrent analysis. Moreover, the result of nitrogen adsorption-desorption isotherm indicated the existence of mesoporous structure in as-prepared sample with hydrothermal process, and specific surface area is significantly higher than the sample obtained by solid-state method. The optimal conditions involved in the photocatalytic reaction, such as TC concentration, catalyst concentration and pH value were investigated.
Organic–inorganic hybrid [H2mdap][BiCl5] showing an above-room-temperature ferroelectric transition with combined order–disorder and displacive origins
Wang, Ya,Shi, Chao,Han, Xiang-Bin
, p. 132 - 136 (2017)
Recently, molecule-based ferroelectric materials have drawn much attention due to their potential multifunctional optoelectronic device applications such as sensors, actuators, optical and memory devices. Therefore, the design of molecular ferroelectrics, explore their ferroelectrics origins and high performance are of significance. In this work, an organic–inorganic hybrid compound [H2mdap][BiCl5] (mdap?=?N-methyl-1,3-diaminopropane; 1) is found to exhibit brilliant ferroelectricity below 372?K. Ferro-paraelectric transition origins the order–disorder of the organic cations and relative displacements of the cis-connected ions in the anionic chains in the crystal lattice via the structural analysis. Second harmonic generation and ferroelectric hysteresis loop measurements reveal typical polarization switching with a spontaneous polarization of 2.38?μC?cm?2 at 353?K.
Doyle, W. P.
, p. 144 - 147 (1958)
Controlled synthesis of a Bi2O3-CuO catalyst for selective electrochemical reduction of CO2 to formate
Dai, Chaoneng,Qiu, Yue,He, Yu,Zhang, Qiang,Liu, Renlong,Du, Jun,Tao, Changyuan
, p. 3493 - 3499 (2019)
The electro-reduction of CO2 to produce energy sources has been considered as a visionary pathway with the help of renewable electricity, which can achieve carbon neutrality and mitigate global warming. Nevertheless, developing a high selectivity, good activity and superior stability catalyst is a big challenge. Here, Bi2O3-CuO(x) bimetallic oxide catalysts were synthesized by a facile coordination-precipitation method with concisely controlled atomic ratios (Cu/Bi). They exhibit a remarkable performance for sufficient reduction of CO2 to formate, achieving a maximum faradaic efficiency of 89.3% at a potential of ?1.4 V vs. SCE. The catalysts are shown to be robust during 10 h of uninterrupted electrolysis. The notable catalytic activity suggests that controlling the Cu/Bi molar ratio is a key factor in developing special micro-structure Bi2O3-CuO(x) catalysts for electrochemical reduction of CO2 to formate in aqueous systems.
Photo-and thermogeneration of singlet oxygen by the metal ions deposited on Al2O3 and SiO2
Shcherbakov,Emel'yanov,Khaula,Il'ichev,Vishnetskaya,Rufov
, p. 799 - 802 (2006)
The specifics of photo-and thermogeneration of singlet molecular oxygen by metal oxides deposited on silica gel and Al2O3 were studied. The deposited oxides were observed to generate equilibrium and superequilibrium concentrations of 1ΔgO2. The V2O5/SiO2 and MoO3/SiO 2 systems were found to be most active in both types of generation. A common mechanism of photo-and thermogeneration was proposed. Pleiades Publishing, Inc., 2006.
Electrochemical synthesis of single-crystal (Ba0.05K0.95)BiO3·1/6H2O with the KSbO3 structure
Jung,Han,Wilson,Payne
, p. 1195 - 1205 (1998)
A new compound with a cubic structure, (Ba0.05K0.95)BiO3·1/6H2O (BKBO), was synthesized by electrochemical crystal growth using a rotating anode in molten KOH flux at 255 °C. The BKBO crystal had the KSbO3 structure and belonged to space group Im3 (No. 204) with Z = 12. Refinement of X-ray diffraction data at room temperature gave a = 10.0204(2) angstroms, V = 1006.1(1) angstroms3, and R = 2.4% for 1465 unique reflections. Potassium, barium, and hydrated oxygen were found to occupy different sites in the tunnel structure. The electrical conductivity at room temperature was similar to the ionic conductor KBiO3. BKBO decomposed to Bi2O3, K2O, and BaO above 400 °C.
Cyganski, A.,Kobylecka, J.
, p. 65 - 78 (1981)
Photocatalyst Bi(OH)SO4 · H2O with High Photocatalytic Performance
Haojie Lu,Wang, Ruiting,Zhang, Linghua,Chen, Daimei,Hao, Qiang,Ma, Chao,Yao, Wenqing
, p. 2075 - 2080 (2018)
Abstract: In this work, Bi(OH)SO4 · H2O, a novel photocatalyst was prepared by a facile method. The sample was characterized by XRD, XPS, SEM, Mott-Schottky curve and ESR. The band gap of Bi(OH)SO4 · H2O is about 4.64 eV, and its CB and VB are estimated at –0.5 and 4.14 eV, respectively. Degradation of RhB and PhOH under UV light irradiation illustrates that the sample has good UV activity. The results of ESR spectra and tapping experiments indicate that the main active species in the photocatalytic reaction process are hydroxyl radicals, superoxide radicals and holes. A possible mechanism of catalytic degradation of organic pollutants was proposed. This semiconductor has a positive valence band and high oxidation capacity theoretically and it may have broad application in synthesizing highly efficient photocatalysts through doping other elements or creating heterojunctions.
Three novel bismuth-based coordination polymers: Synthesis, structure and luminescent properties
Kan, Liang,Li, Jiantang,Luo, Xiaolong,Li, Guanghua,Liu, Yunling
, p. 70 - 73 (2017)
Three novel bismuth-based coordination polymers, [(CH3)2NH2][Bi(pdc)(bdc)]·2DMF, [(CH3)2NH2][Bi(tdc)2]·1.5DMF and [Bi(bpdc)2H2O]·xGuest (compounds 1–3) (H2pdc = 3,5-pyridinedicarboxylic acid, H2bdc = 1,4-benzenedicarboxylic acid, H2tdc = 2,5-thiophenedicarboxylic acid, H2bpdc = 4,4′-biphenyldicarboxylic acid), have been successfully synthesized under solvothermal conditions and characterized by single crystal X-ray diffraction. Compounds 1 and 2, which are constructed by 9-coordinated or 8-coordinated Bi3 +, feature three-dimensional structures with hms and dia topology, respectively. However, 5-coordinated Bi3 + based compound 3 is a two-dimensional layered structure. Compound 1 can tune emissive performance by doping different lanthanide ions Tb3 +, Eu3 + and Dy3 +. Furthermore, detection of nitro explosives is investigated. All of the compounds are characterized by elemental analysis, IR spectrum and thermogravimetric analysis.
A new method of synthesis of BiFeO3 prepared by thermal decomposition of Bi[Fe(CN)6]?4H2O
Navarro,Lagarrigue,De Paoli,Carbonio,Gomez
, p. 655 - 660 (2010)
In order to investigate the formation of the multiferroic BiFeO 3, the thermal decomposition of the inorganic complex Bismuth hexacyanoferrate (III) tetrahydrate, Bi[Fe(CN)6]?4H2O has been studied. The starting material and the decomposition products were characterized by IR spectroscopy, thermal analysis, laboratory powder X-ray diffraction, and microscopic electron scanning. The crystal structures of these compounds were refined by Rietveld analysis. BiFeO3 were synthesized by the decomposition thermal method at temperature as low as 600 °C. There is a clear dependence of the type and amount of impurities that are present in the samples with the time and temperature of preparation.
Electrochemistry of powder material studied by means of the cavity microelectrode (CME)
Cachet-Viviera,Vivier,Cha,Nedelec,Yu
, p. 181 - 189 (2001)
The kinetic aspects of powder material electrochemistry can be studied using the cavity microelectrode (CME) as it allows carrying out voltammetry at scan rates between a few millivolts per second to several hundreds of volts per second. Thus, significant voltammogram characteristics-scan rate profiles can be drawn. Theoretical models suited to each material needs to be developed for their exploitation. First, we report significant results obtained with CME on powder materials. The materials studied were chosen for their wide variety of possible applications such as battery materials (polyaniline or Bi2O3, which modifies the electrochemical behavior of materials in which it is included), supercapacitor (carbon black), and for the electrocatalytic hydrogenation of organic compounds (PtO2). Secondly, we briefly describe the general action for establishing models to obtain a better understanding of the electrochemical processes.
Combined photocatalytic degradation of pollutants and inactivation of waterborne pathogens using solar light active α/β-Bi2O3
Channa, Najeebullah,Gadhi, Tanveer A.,Mahar, Rasool Bux,Chiadò, Alessandro,Bonelli, Barbara,Tagliaferro, Alberto
, (2021)
A solar light active composite of α/β-Bi2O3 was synthesized using a chemical-free solid-state reduction method. The obtained composite was characterized by X-ray diffraction, UV–vis spectroscopy, field emission scanning electron microscopy, and zeta potential. Initially, to validate the photocatalytic effectiveness, the obtained α/β-Bi2O3 composite was used to degrade indigo carmine dye. Then, the inactivation of E. coli and S. aureus waterborne pathogens was performed on solid and in liquid media. On solid agar media, a significant inhibition zone was observed for both bacterial strains. Similarly, in liquid culture, these strains E. coli and S. aureus were reduced from 1 × 106 CFU/mL to a few CFU/mL, after 240 min of photocatalytic exposure. Furthermore, mixed wastewater of indigo carmine and E. coli/S. aureus were tested to study the combined photocatalytic mechanism against the organic dye and microorganisms. Overall, the obtained results suggested the efficacy of α/β-Bi2O3 towards visible light inactivation of bacteria even in combination with other pollutants, highlighting the great potential of the advanced photocatalytic process for combined treatment of organic pollutants and pathogens.
Automated diffraction tomography for the structure elucidation of twinned, sub-micrometer crystals of a highly porous, catalytically active bismuth metal-organic framework
Feyand, Mark,Reimer, Tim,Stock, Norbert,Mugnaioli, Enrico,Kolb, Ute,Dieterich, Johannes M.,Vermoortele, Frederik,Bueken, Bart,De Vos, Dirk
, p. 10373 - 10376,4 (2012)
A combined approach: A permanent highly porous bismuth-containing metal-organic framework (CAU-7) has been synthesized and its structure determined by a combination of electron diffraction, Rietveld refinement, and DFT calculations. The compound is catalytically active in the hydroxymethylation of furan (see picture). Copyright
Precipitation of bismuth(III) oxobromide from bromide media
Novokreshchenova,Daminova,Yukhin
, p. 2015 - 2019 (2007)
Abstract-X-ray phase analysis, thermogravimetry, IR spectroscopy, and chemical analysis were used to study bismuth(III) precipitation from nitrate solutions upon addition of aqueous solutions of hydrobromic acid or ammonium bromide, and from bismuth-containing hydrobromic acid solutions. The conditions in which bismuth(III) oxobromide of BiOBr composition is formed were determined and the possibility of obtaining a high-purity product was assessed.
Low-temperature vacuum reduction of BiMnO3
Belik, Alexei A.,Matsushita, Yoshitaka,Tanaka, Masahiko,Takayama-Muromachi, Eiji
, p. 7685 - 7689 (2011)
Low-temperature vacuum reduction was used for the preparation of the oxygen-deficient BiMnO2.81 sample in a bulk form from stoichiometric BiMnO3. The transformation occurs in vacuum better than 10 -3 Pa at a narrow temperature range of 570-600 K. The structure of the new phase was analyzed using synchrotron X-ray powder diffraction data. BiMnO2.81 crystallizes in a perovskite-type cubic structure (space group I-43d) with a = 15.88552(5) A corresponding to a 4ap superstructure, where ap is the parameter of the cubic perovskite subcell. Oxygen vacancies are ordered, and one oxygen site in BiMnO 2.81 is completely vacant, resulting in MnO5 pyramids. BiMnO2.81 is rather unstable in air and slowly restores its oxygen content even at room temperature.
Optical properties of bismuth oxide thin films prepared by reactive d.c. magnetron sputtering onto p-GaSe (Cu)
Leontie, Liviu,Caraman,Evtodiev, Igor,Cuculescu, Elmira,Mija, Ana
, p. 2052 - 2056 (2008)
Bismuth oxide (Bi2O3) thin films with thickness in the range 20-160 nm have been deposited by d.c. reactive magnetron sputtering of Bi in an atmosphere Ar:O2 (1:1), onto single crystalline p-GaSe (Cu) substrates. The optic
Bi2O3 and g-C3N4 quantum dot modified anatase TiO2 heterojunction system for degradation of dyes under sunlight irradiation
Peng, Weidong,Yang, Chun,Yu, Jiang
, p. 1181 - 1190 (2019)
A facile and feasible method was successfully utilized to incorporate Bi2O3 and g-C3N4 quantum dots on TiO2 surface to synthesize a novel composite g-C3N4/TiO2/Bi2O3. The photocatalytic activity of the composite g-C3N4/TiO2/Bi2O3 for degradation of dyes under sunlight and UV light irradiation was evaluated. It possessed the higher photocatalytic performance than that of pristine TiO2 or g-C3N4 under the same conditions. Under sunlight irradiation, the reaction rate constants of the g-C3N4/TiO2/Bi2O3 was about 4.2 times and 3.3 times higher than that of TiO2 and g-C3N4, respectively. The promising photocatalytic performance was attributed to the broader light absorption range and efficient separation of photoinduced carriers. Moreover, based on the TEM, XPS, XRD, UV-vis spectrum, radicals scavenging test and Mott-Schottky analysis systematic mechanism for photodegradation process was proposed. This work provides a promising strategy for the modification of TiO2-based semiconductors by incorporating different quantum dots and promoting the efficiency of the photocatalysts in practical application.
Development of BiOI as an effective photocatalyst for oxygen evolution reaction under simulated solar irradiation
Chen, Tzu-Hsin,Hu, Chechia,Lin, Kun-Yi Andrew,Tsunekawa, Shun,Wu, Jia-Hao,Yoshida, Masaaki
, p. 3223 - 3231 (2020)
In this study, crystalline BiOI powders were prepared for photocatalytic O2evolution in the presence of NaIO3as the electron mediator. BiOI with a microspherical morphology, a layered structure composed of [Bi2O2]2+and intercalated I?ions, exhibited a suitable valence band level to generate photoexcited holes for O2evolution. Moreover, ruthenium was loaded using the impregnation or photodeposition method to produce RuO2as a co-catalyst to improve the photocatalytic activity of BiOI. Photodeposited RuO2-loaded BiOI showed a high O2evolution rate of 2730 μmol h?1and can be reused eight times in the presence of NaIO3under simulated solar irradiation. The high photocatalytic O2evolution can be attributed to the highly dispersed RuO2, which could serve as an effective electron sink, on the surface of BiOI and its enhanced visible light-harvesting ability. Besides, the presence of NaIO3in the system was effective to receive photoexcited electrons from RuO2-loaded BiOI for improving charge separation and hence the O2evolution from RuO2sites on the BiOI surface. The RuO2-loaded BiOI with high photocatalytic activity and stability for generating O2could be a potential candidate for achieving overall water splitting in aZ-scheme system in the presence of NaIO3for solar utilization in the future.
Formation of Nd1–xBixFeO3 Nanocrystals under Conditions of Glycine-Nitrate Synthesis
Karpov,Tomkovich,Tugova
, p. 2133 - 2138 (2018)
Nd1–xBixFeO3 nanocrystals with crystallite size 30?60 nm have been prepared under conditions of glycine–nitrate burning. Single-phase Nd1–xBixFeO3 nanocrystals are formed over the entire studied concentrations range if the glycine–nitrate synthesis is performed in excess of the oxidizer. Under these conditions, a continuous range of the Nd1–xBixFeO3 solid solutions (0 ≤ х ≤ 0.75) crystallized in the rhombic system (space group Pbnm) are formed without crystallization of the burning intermediates. The Nd1–xBixFeO3 solid solutions (х = 0.775, 0.8) crystallize in the rhombic system (space group Pbаm).
The synthesis of pure-phase bismuth ferrite in the Bi-Fe-O system under hydrothermal conditions without a mineralizer
Gajovic, Andreja,Sturm, Sago,JanWar, Bogtjan,Santic, Ana,Zagar, Kristina,Cehz, Miran
, p. 3173 - 3179 (2010)
Bismuth ferrite, BiFeO3 (BFO), was synthesized in a hydrothermal process without the introduction of any metal cations, other than Fe 3+ and Bi3+. For this purpose, a strong organic hydroxide was used for the precipitation of the bismuth and iron salts. With the aim to study the molar range for the production of BFO in the Bi-Fe-O system under hydrothermal conditions, the complexity of the phases appearing after the reaction was investigated. Pure-phase BFO was achieved in the case of a hydrothermal treatment after the coprecipitation of a solution of bismuth and iron salts containing an equimolar ratio of Bi3+ and Fe3+ ions. Various iron and bismuth compounds having different morphologies were achieved by changing the Bi3+:Fe3+ ratios in the reaction, but no other bismuth iron oxide phases were observed. To obtain a complete picture of the compounds, we compared the results from transmission electron microscopy with those from X-ray powder diffraction, energy-dispersive X-ray spectroscopy, and scanning electron microscopy. The dielectric properties of the pure BFO and a multiphase system were compared. The pure BFO shows a higher dielectric permittivity than the multiphase system and is comparable with the values reported in the literature.
A simple preparation of carbon doped porous Bi2O3 with enhanced visible-light photocatalytic activity
Dai, Gaopeng,Liu, Suqin,Liang, Ying
, p. 44 - 48 (2014)
Carbon doped bismuth oxide (Bi2O3) with a porous structure is obtained by a simply calcination of bismuth nitrate pentahydrate (Bi(NO3)3.5H2O) in glycol solution. The as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and UV-Vis absorption spectroscopy. The photocatalytic activity was evaluated by the photocatalytic degradation of methyl orange (MO) in an aqueous solution under visible-light radiation (λ > 420 nm). The results show that carbon was incorporated into the lattice of Bi2O3. The absorption intensity of C-doped Bi2O3 increases in the region of 450-530 nm and the absorption edge has an obvious shift to long wavelength. The C-doped Bi2O3 exhibited much higher photocatalytic activity than the pure one due to the synergetic effects of the porous structure and the improved absorption in the visible-light region.
In-situ growth UiO-66 on Bi2O3 to fabrication p-p heterojunction with enhanced visible-light degradation of tetracycline
Duan, Zhengzhou,Hou, Dongmei,Li, Chuwen,Meng, Chunfeng,Tang, Jijun,Xv, Qinyun,Zhang, Qiyuan,Zhang, Tang,Zhang, Yamei,Zhu, Yu
, (2021/07/06)
A p-p heterostructure has been constructed through loading UiO-66 on Bi2O3 as a composite photocatalyst to degrade the antibiotic tetracycline (TC) under visible light. The Bi2O3@UiO-66 composites were characterized by XRD, SEM, UV, BET, PL and FTIR. The formed p-p heterojunction improves the separation efficiency of electrons and holes, which caused the degradation rate constant of the composite photocatalyst for TC reaching 0.0492 min-1. The UiO-66 is added to improve the TC adsorption capacity and photocatalytic stability of the composite photocatalyst, so that the composite photocatalyst can have a photodegradation effect on TC under different anion and cation environments or a strong acid-base solution environment with the pH value of 1~13. The photoelectrochemical analyses is the evidence of the fast transfer of electron and hole pairs with inhibiting recombination.
Synthesis of Bi2O3@BiOI@UiO-66 composites with enhanced photocatalytic activity under visible light
Tang, Jijun,Zhang, Tang,Duan, Zhengzhou,Li, Chuwen,Meng, Chunfeng,Zhang, Yamei,Zhang, Qiyuan,Hou, Dongmei,Xv, Qinyun,Zhu, Yu
, (2021/02/16)
Bi2O3 is a photocatalyst with excellent performance; however, its applications are limited due to its wide bandgap. In this paper, by adding BiOI and the metal–organic framework UiO-66, a Bi2O3@BiOI@UiO-66 composite material is obtained with high adsorption capacity, in which the bandgap of Bi2O3 is reduced, the recombination of photogenerated electrons and holes is prevented, the photocatalytic efficiency and stability are improved. In visible light degradation experiments, Bi2O3@BiOI@UiO-66 has obvious degradation effects on Rhodamine B and tetracycline, which are 22.2 and 1.04 times that of pure Bi2O3, respectively. Bi2O3@BiOI@UiO-66 demonstrats its potential as photocatalytic degradation material.
