Photochemical Synthesis of Selenium Nanospheres of Tunable Size and Colloidal Stability with Simple Diketones

Abstract

Temporal and spatial segregations are two fundamental requirements for the successful synthesis of nanoparticles (NPs). To obtain colloidally stable selenium nanospheres (SeNSs), surfactants or polymers are generally needed as structure-directing agents or stabilizers in the reduction approaches for SeNP synthesis. The addition of such chemicals sacrifices the purity of the obtained SeNPs and, therefore, is detrimental to the applications. Here, for the first time, we report that low-molecular weight (less than six carbons) diketones are excellent photoreductants for green and tunable synthesis of SeNPs, owing to their merits in temporal and spatial control. With simple diketones as the photoreductants, the resultant SeNPs were pure and colloidally stable with nice photoelectronic properties. This finding not only provides a useful strategy for the synthesis of SeNPs but also might be a milestone in the development of ketone photochemistry.

UV-Induced Redox Conversion of Tellurite by Biacetyl

“…It is reported that UV/AA is feasible for tunable synthesis of Se nanospheres by regulating either the light intensity or the concentration of AA. 22 In the photochemical processes, BD shares some similarity with AA. 38 We expect that the UV/BD approach should have a good tunability for the generation of Te nanoparticles.…”

“…The two peaks in the XPS spectrum of the obtained particles were identical to those of Te 0 (Figure d). , These results demonstrate the potential of the UV/BD method for Te resource recovery. It is reported that UV/AA is feasible for tunable synthesis of Se nanospheres by regulating either the light intensity or the concentration of AA . In the photochemical processes, BD shares some similarity with AA .…”

“…21 In a recent work, the combination of UV and diketones was found to be an effective approach for the synthesis of selenium (Se) nanospheres from selenite. 22 Both Se and Te belong to the chalcogen group. Nevertheless, Te is regarded as a maverick among the chalcogens.…”

“…24 Under UV irradiation, BD generates the reductive acetyl radical [CH 3 C • (O)] at a high quantum yield. 22 In the presence of dissolved oxygen (DO), the CH 3 C • (O) would be oxidized to the acetyl peroxyl radical (CH 3 CO 3…”

“…Biacetyl, also named as 2,3-butanedione (BD), is the simplest diketone that exists in all living things and has been widely used as a food additive . Under UV irradiation, BD generates the reductive acetyl radical [CH 3 C • (O)] at a high quantum yield . In the presence of dissolved oxygen (DO), the CH 3 C • (O) would be oxidized to the acetyl peroxyl radical (CH 3 CO 3 • ), and then to acetic acid and ultimately to carbon dioxide.…”