Double Z-scheme system of silver bromide@bismuth tungstate/tungsten trioxide ternary heterojunction with enhanced visible-light photocatalytic activity.

Title Double Z-scheme system of silver bromide@bismuth tungstate/tungsten trioxide ternary heterojunction with enhanced visible-light photocatalytic activity.
Authors M. Zhang; Y. Zhu; W. Li; F. Wang; H. Li; X. Liu; W. Zhang; C. Ren
Journal J Colloid Interface Sci
DOI 10.1016/j.jcis.2017.08.095
Abstract

The ternary heterojunction of silver bromide@bismuth tungstate/tungsten trioxide (AgBr@BiWO/WO) was designed and synthesised by hydrothermal and deposition-precipitation approaches. The composites were characterised by X-ray diffraction, transmission electron microscopy and X-ray photoelectron spectroscopy (XPS). The photoabsorption range and bandgaps of the photocatalysts were analysed by ultraviolet-visible diffuse reflectance spectroscopy (UV-vis DRS). Compared with BiWO/WO or AgBr alone, the AgBr@BiWO/WO composites displayed higher visible-light photocatalytic performance for degrading rhodamine B (RhB). AgBr@BiWO/WO with 40% AgBr concentration was optimum for photocatalytic activity. Radical-trapping experiments revealed that superoxide anion radicals (O) and holes (h) were the active species during photocatalytic degradation and that O was the dominant active species. Therefore, the increased photocatalytic activity of AgBr@BiWO/WO was attributed to the atypical double Z-scheme system, which effectively improved the transfer and separation of electron-hole pairs in ternary heterojunction structures.

Citation M. Zhang; Y. Zhu; W. Li; F. Wang; H. Li; X. Liu; W. Zhang; C. Ren.Double Z-scheme system of silver bromide@bismuth tungstate/tungsten trioxide ternary heterojunction with enhanced visible-light photocatalytic activity.. J Colloid Interface Sci. 2018;509:1824. doi:10.1016/j.jcis.2017.08.095

Related Elements

Tungsten

See more Tungsten products. Tungsten (atomic symbol: W, atomic number: 74) is a Block D, Group 6, Period 6 element with an atomic weight of 183.84. The number of electrons in each of tungsten's shells is [2, 8, 18, 32, 12, 2] and its electron configuration is [Xe] 4f14 5d4 6s2. Tungsten Bohr ModelThe tungsten atom has a radius of 139 pm and a Van der Waals radius of 210 pm. Tungsten was discovered by Torbern Bergman in 1781 and first isolated by Juan José Elhuyar and Fausto Elhuyar in 1783. In its elemental form, tungsten has a grayish white, lustrous appearance. Elemental TungstenTungsten has the highest melting point of all the metallic elements and a density comparable to that or uranium or gold and about 1.7 times that of lead. Tungsten alloys are often used to make filaments and targets of x-ray tubes. It is found in the minerals scheelite (CaWO4) and wolframite [(Fe,Mn)WO4]. In reference to its density, Tungsten gets its name from the Swedish words tung and sten, meaning heavy stone.

Bismuth

See more Bismuth products. Bismuth (atomic symbol: Bi, atomic number: 83) is a Block P, Group 15, Period 6 element with an atomic radius of 208.98040. The number of electrons in each of Bismuth's shells is 2, 8, 18, 32, 18, 5 and its electron configuration is [Xe] 4f14 5d10 6s2 6p3. Bismuth Bohr ModelThe bismuth atom has a radius of 156 pm and a Van der Waals radius of 207 pm. In its elemental form, bismuth is a silvery white brittle metal. Bismuth is the most diamagnetic of all metals and, with the exception of mercury, its thermal conductivity is lower than any other metal. Elemental BismuthBismuth has a high electrical resistance, and has the highest Hall Effect of any metal (i.e., greatest increase in electrical resistance when placed in a magnetic field). Bismuth is found in bismuthinite and bismite. It is also produced as a byproduct of lead, copper, tin, molybdenum and tungsten extraction. Bismuth was first discovered by Early Man. The name Bismuth originates from the German word 'wissmuth,' meaning white mass.

Silver

See more Silver products. Silver (atomic symbol: Ag, atomic number: 47) is a Block D, Group 11, Period 5 element with an atomic weight of 107.8682. Silver Bohr ModelThe number of electrons in each of Silver's shells is 2, 8, 18, 18, 1 and its electron configuration is [Kr]4d10 5s1. The silver atom has a radius of 144 pm and a Van der Waals radius of 203 pm. Silver was first discovered by Early Man prior to 5000 BC. In its elemental form, silver has a brilliant white metallic luster. Elemental SilverIt is a little harder than gold and is very ductile and malleable, being exceeded only by gold and perhaps palladium. Pure silver has the highest electrical and thermal conductivity of all metals and possesses the lowest contact resistance. It is stable in pure air and water, but tarnishes when exposed to ozone, hydrogen sulfide, or air containing sulfur. It is found in copper, copper-nickel, lead, and lead-zinc ores, among others. Silver was named after the Anglo-Saxon word "seolfor" or "siolfur," meaning 'silver'.

Bromine

See more Bromine products. Bromine (atomic symbol: Br, atomic number: 35) is a Block P, Group 17, Period 4 element. Its electron configuration is [Ar]4s23d104p5. The bromine atom has a radius of 102 pm and its Van der Waals radius is 183 pm. In its elemental form, bromine Bromine Bohr Model has a red-brown appearance. Bromine does not occur by itself in nature; it is found as colorless soluble crystalline mineral halide salts. Bromine was discovered and first isolated by Antoine Jérôme Balard and Leopold Gmelin in 1825-1826.

Related Forms & Applications