Preparation of Silver Carbonate and its Application as Visible Light‐driven Photocatalyst Without Sacrificial Reagent

Abstract

Visible light-driven photocatalyst is the current research focus and silver oxyacid salts with p-block elements are the promising candidates. In this research, Ag2 CO3 was prepared by a facile precipitation method and used to degrade the pollutants from waters. The results revealed that the silver carbonate with monoclinic structure quickly decomposed methyl orange and rhodamine B in less than 15 min under visible light irradiation. When it was recycled six times, the degradation of methyl orange still can reach 87% after 30 min. The calculated band gap of Ag2 CO3 was 2.312 eV with Valence band edge potential of 2.685 eV and Conduction band 0.373 eV vs NHE, which endowed the excellent photo-oxidation ability of silver carbonate. Photogenerated holes and ozone anion radicals were the primary active species in the photo-oxidization degradation of dye. The generation of metallic silver resulted from photocorrosion and the consequent reduction in the ozone anion radical amount led to the performance degradation of Ag2 CO3 . The simple preparation method and high photocatalytic performance of Ag2 CO3 increases its prospect of application in future.

Heterojunction-based photocatalytic nitrogen fixation: principles and current progress

“…Depending on the material, under light illumination, semiconductors can be oxidised or reduced, resulting in the decomposition of the semiconductor material and subsequent deactivation of the photocatalysts 67 . For example, in the case of metal sulphides, sulphide ions (S 2-) are usually oxidised by holes to form sulphate ions (SO4 2-) or sulphur 68 , while silver-based materials are reduced to metallic Ag 0 by the photogenerated electrons 69 . Additionally, the reactionary intermediates of NRR can also act as catalyst poison or occupy N2 adsorption sites, resulting in sluggish reaction kinetics.…”

“… 67 For example, in the case of metal sulphides, sulphide ions (S 2− ) are usually oxidised by holes to form sulphate ions (SO 4 2− ) or sulphur, 68 while silver-based materials are reduced to metallic Ag 0 by the photogenerated electrons. 69 Additionally, the reaction intermediates of the NRR can also act as a catalyst poison or occupy N 2 adsorption sites, resulting in sluggish reaction kinetics. Therefore, a commercially viable photocatalyst must possess not only high efficiency but also structural stability throughout prolonged cyclic runs.…”

Cyclodextrin functionalization enhancement in a CA-β-CD/g-C3N4/Ag2CO3 Z-type heterojunction towards efficient photodegradation of organic pollutants

“…Typical examples include Ag 2 O and its derivative Ag-based oxides. 11 Vidyasagar et al prepared Ag/AgO/g-C 3 N 4 which showed lower charge transfer resistance and better degradation efficiency for acid violet-7 dye. 12 Zhang et al successfully prepared a Ag 3 PO 4 /g-C 3 N 4 heterojunction photocatalyst by an in situ deposition method, the degradation rate of RhB was 99.4%, and the degradation rate constant is 4.1 times and 20.0 times higher than those of pure Ag 3 PO 4 and g-C 3 N 4 .…”

KBiO3 as an Effective Visible-Light-Driven Photocatalyst: Stability Improvement by In Situ Constructing KBiO3/BiOX (X = Cl, Br, I) Heterostructure

“…With the rapid development of industry, organic pollutants are produced, posing a threat to human health and the ecological environment. , Photocatalysis technology, as an advanced oxidation technology, has a good application prospect in the treatment of organic pollutants . As a typical photocatalyst, TiO 2 has strong oxidizing ability, but its wider forbidden bandwidth and photogenerated electron–hole recombination frequency limit the actual application, and promotes the development of visible-light-driven photocatalysts. − Therefore, various semiconductors, such as perovskite, , carbon nitride (C 3 N 4 ), silver-containing compounds, − vanadium-containing compounds, − and doped TiO 2 , , have been developed. Therein, bismuth-based semiconductors exhibit an attractive application prospect due to their excellent performance and stability resulted from the particular electronic structure and wide light absorption spectrum. , …”