Synthesis and characterization of nanoscale composite particles formed by 2D layers of Cu–Fe sulfide and Mg-based hydroxide

Abstract

We propose a simple hydrothermal synthesis of nanoflakes composed of alternating sulfide and hydroxide quasi-monolayers and their aqueous colloids, as a prospective family of novel multifunctional 2D materials.

Facile synthesis and selected characteristics of two-dimensional material composed of iron sulfide and magnesium-based hydroxide layers (tochilinite)

“…The spectra are better fitted with additional doublets at 162.6 eV and B163.5 eV, which arise from some S-S bonding. The first ''disulfide'' component is believed 50,[65][66][67][68][69] to originate from terminal atoms bearing higher negative charge in À S-S n -S À anions rather than central ''polysulfide'' atoms; their relative intensities suggest that mainly trisulfide anions form in the iron-deficient sulfidic layers. A wide maximum between 164 eV and 165 eV seems to be a satellite related to electron transfer onto empty Fe 3d states.…”

“…A wide maximum between 164 eV and 165 eV seems to be a satellite related to electron transfer onto empty Fe 3d states. 50,[65][66][67][68][69] The contributions of oxysulfur species at the BE above 168 eV are weak and arise from adsorbed sulfate.…”

“…Valleriite (CuFeS 2 )Á(Mg,Al,-Fe)(OH) 2 [19][20][21][22][23][24][25][26][27] and tochilinite mFeSÁn(Mg,Fe)(OH) 2 [30][31][32][33][34][35][36] are the most known of them; particularly, valleriite ores of the Noril'sk ore provenance (Russia) are of commercial importance but not involved in the exploitation because of the lack of processing technologies. Synthetic valleriite and tochilinite have been prepared and characterized too; [37][38][39][40][41][42][43][44][45][46][47][48][49][50][51] however, the yield of the substances was typically lower than 50%, and those were substantially contaminated by the reaction by-products. Another group of layered iron chalcogenide-hydroxide materials with the composition Fe(Se,S)Á(Li,Fe)OH and some their derivatives [52][53][54][55][56] synthesized in the recent years are attracting much attention because of the superconducting properties but little efforts have been made to study other characteristics and potential applications.…”

“…Further progress requires, first of all, robust methods for production of pure materials and tailoring their basic characteristics. Recently, 50 we proposed a hydrothermal synthesis of valleriite (CuFeS 2 )Á (Mg,Al,Fe)(OH) 2 , examined the effect of dopants entered magnesium hydroxide (Al, Li) or both sulfide and hydroxide layers (Co, Ni, Cr), and studied the electronic structure, physical and chemical characteristics as a function of the composition. The aims of the current research were to develop a reliable preparation procedure and to elucidate specific features of the tochilinite-type materials.…”

“…Then the dispersions were transferred to an in-home made stainless steel autoclave with Teflon liner. 50 Alternatively, all the reagents were simultaneously loaded into the autoclave, and pH was adjusted with aqueous ammonia to B11. Both procedures were found to lead to essentially the same results.…”