Solvothermal synthesis of CdIn2S4 photocatalyst for selective photosynthesis of organic aromatic compounds under visible light

Abstract

Ternary chalcogenide semiconductor, cadmium indium sulfide (CdIn 2 S 4 ), was prepared by a simple solvothermal method using ethylene glycol as a solvent, as well as indium chloride tetrahydrate (InCl 3 . 4H 2 O), cadmium nitrate tetrahydrate [Cd(NO 3 ) 2 . 4H 2 O], and thiacetamide (TAA) as precursors. The resulted sample was subject to a series of characterizations. It is the first time to use CdIn 2 S 4 sample as a visible light-driven photocatalyst for simultaneous selective redox transformation of organic aromatic compounds. The results indicate that the as-synthesized CdIn 2 S 4 photocatalyst not only has excellent photocatalytic performance compared with pure In 2 S 3 and CdS for the selective oxidation of aromatic alcohols in an oxygen environment, but also shows high photocatalytic redox activities under nitrogen atmosphere. A possible mechanism for the photocatalytic redox reaction in the coupled system was proposed. It is hoped that our current work could extend the applications of CdIn 2 S 4 photocatalyst and provide new insights for selective transformations of organic compounds.The photocatalytic technology has attracted much attention for the scholars of different fields since Fujishima and Honda found that TiO 2 as electrode can decompose water to produce hydrogen and oxygen in 1972 1 . With the development of photocatalytic technology, current research work mainly focuses on the degradation of organic pollutants 2-4 , hydrogen production in water 5 , reduction of carbon dioxide 6 , selective oxidation of different alcohols 7 , and other kinds of organic transformation reactions [8][9][10] . Among them, selective oxidation of alcohols to corresponding aldehydes without further oxidation to carboxylic acids and carbon dioxide has become a research hotspot recently 11,12 . This is because that the selective oxidation of aromatic alcohols into corresponding aldehydes is one of the most fundamental reactions in organic synthesis and fine chemical industry 13 . Traditional oxidants and reductants, such as KMnO 4 , ClO − , Fe, and Pt used in the redox process generally have toxicity, corrosivity, or preciousness. Additionally, these reaction systems are not only quite complicated, but also produce a lot of wastes. Therefore, one of the challenges as well as opportunities faced by the researchers is to develop a high-efficienct and environmental friendly method for selective organic transformations under mild conditions 14 .It has been reported that semiconductor photocatalysts can be applied in the selective oxidation of alcohols to aldehydes rather than CO 2 and H 2 O in the final products 15 . For example, Xu's group reported that CdS was introduced as an efficient visible light photocatalyst for selective oxidation of saturated primary C-H bonds under ambient conditions 16 . Panda's group found efficient photocatalytic selective nitro-reduction and C-H bond oxidation over ultrathin sheet mediated CdS flowers 17 . Wang and his coworkers reported molecular and textural engineering of conjugated carbon...

Crystal Chemistry, Optical–Electronic Properties, and Electronic Structure of Cd1–xIn2+2x/3S4 Compounds (0 ≤ x ≤ 1), Potential Buffer in CIGS-Based Thin-Film Solar Cells

“…Table S4 in the Supporting Information summarizes measured binding energies that agree with reported values for the In 3+ and Cd 2+ cations. 2 Note that the intensity of the Cd 3d doublet drastically decreases with x while one of the In 3d doublet increases very slightly. This result clearly indicates a preferential localization of indium at the surface for high x values and could be assigned to a migration phenomenon of Cd vacancies toward the uppermost layers.…”

Synthesis of novel C-doped g-C3N4 nanosheets coupled with CdIn2S4 for enhanced photocatalytic hydrogen evolution

“…As visible-light-active photocatalysts, ternary metal sulfide (e.g., ZnIn 2 S 4 and CdIn 2 S 4 ) have attracted great attention because of the suitable band edge and band gap, as well as tunable optical properties [23–28]. For example, CdIn 2 S 4 has been reported in various photoredox catalysis, such as organic photosynthesis, CO 2 photoreduction and H 2 evolution [29–31]. Despite these advances, the photocatalytic performance of CdIn 2 S 4 alone is barely satisfactory, mainly due to the low separation and migration efficiency of photogenerated charge carriers.…”

Evidence for Allele-Specific Levels of Enhanced Susceptibility of Wheat mlo Mutants to the Hemibiotrophic Fungal Pathogen Magnaporthe oryzae pv. Triticum

“…The usage of multiple independent mlo alleles would greatly improve the credibility of such comparative analyses. Similar to barley mlo mutants, Arabidopsis powdery mildew-resistant mlo mutants show, in part, altered infection phenotypes to a range of other microorganisms [ 12 , 23 , 61 ]. However, no clear pattern regarding lifestyle, tissue preference or mode of colonization emerged from these assays.…”