Synthetic Mechanism Studies of Iron Selenides: An Emerging Class of Materials for Electrocatalysis

Abstract

Solution-processed iron selenide nanocrystals (NCs) have recently attracted considerable attention in electrocatalysis water splitting. Nevertheless, a primary challenge in current iron-based NCs chemical synthesis is controlling phase purities between each chalcogen (monochalcogenide, dichalcogenides, and oxides), which requires a comprehensive understanding of the reaction mechanisms at the early stages of nucleation. Herein, we investigate the fundamental steps in transforming molecular organoiron and organoselenium precursors to iron selenides NCs with the view of developing universal synthesis protocols for phase pure metal selenium and metal oxides NCs. The main intermediate species and volatile by-products are identified by high-resolution electron microscopy and Nuclear Magnetic Resonance (NMR) spectroscopy (1H, 13C, and 31P). Experimental evidence suggests that the phase determining factor is the coordinating reactivity difference between olefins (1-octadecene, oleylamine), tributylphosphine and trioctylphosphine associated with their corresponding Se bond cleavage. This work proposes organoselenium interconversion reaction mechanisms during iron selenides synthesis, offering a universal synthetic strategy for other electrocatalytically or photocatalytically active layered metal selenides materials.

Dynamic and Steady-State Investigation of the Band Energy Distributions and Electronic Properties of Cu2ZnSnS4 and Cu2ZnSnSe4 Nanocrystals Utilizing Electrochemical Techniques

“…[4,8,24] Since we calculated the bandgap of the CZTSe spectrum cut before the tale end, which may result in the value of CZTSe being bigger than CZTS. [25] In order to further investigate the bandgap of these materials, a systematic electrochemistry analysis was performed in the following sections.…”

Facile Photochemical/Thermal Assisted Hydration of Alkynes Catalysed under Aqueous Media by a Chalcogen Stabilized, Robust, Economical, and Reusable Fe3Se2(CO)9 Cluster

“…The powder XRD pattern is similar to JCPDS card no. 850735 [67][68][69][70]. The surface morphologies of the FeSe nanoparticles were investigated through FESEM images.…”

Augmenting the band gap of iron diselenide pyrite via ruthenium alloy integration

“…Among these materials, iron selenide stands out for its significant absorption coefficient, narrow band gap, and potential utility in photovoltaic cells [ [10] , [11] , [12] , [13] , [14] , [15] ]. Consequently, iron selenide has emerged as a viable alternative to conventional silicon (Si) in photovoltaic applications [ [16] , [17] , [18] , [19] ]. Noteworthy is the fact that iron selenides exhibit the dual properties of semiconductors and superconductors, coupled with magnetic light absorption capabilities [ [20] , [21] , [22] ].…”