Two-Dimensional Tin Selenide Nanostructures for Flexible All-Solid-State Supercapacitors

Abstract

Due to their unique electronic and optoelectronic properties, tin selenide nanostructures show great promise for applications in energy storage and photovoltaic devices. Despite the great progress that has been achieved, the phase-controlled synthesis of two-dimensional (2D) tin selenide nanostructures remains a challenge, and their use in supercapacitors has not been explored. In this paper, 2D tin selenide nanostructures, including pure SnSe2 nanodisks (NDs), mixed-phase SnSe-SnSe2 NDs, and pure SnSe nanosheets (NSs), have been synthesized by reacting SnCl2 and trioctylphosphine (TOP)-Se with borane-tert-butylamine complex (BTBC) and 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone. Utilizing the interplay of TOP and BTBC and changing only the amount of BTBC, the phase-controlled synthesis of 2D tin selenide nanostructures is realized for the first time. Phase-dependent pseudocapacitive behavior is observed for the resulting 2D nanostructures. The specific capacitances of pure SnSe2 NDs (168 F g(-1)) and SnSe NSs (228 F g(-1)) are much higher than those of other reported materials (e.g., graphene-Mn3O4 nanorods and TiN mesoporous spheres); thus, these tin selenide materials were used to fabricate flexible, all-solid-state supercapacitors. Devices fabricated with these two tin selenide materials exhibited high areal capacitances, good cycling stabilities, excellent flexibilities, and desirable mechanical stabilities, which were comparable to or better than those reported recently for other solid-state devices based on graphene and 3D GeSe2 nanostructures. Additionally, the rate capability of the SnSe2 NDs device was much better than that of the SnSe NS device, indicating that SnSe2 NDs are promising active materials for use in high-performance, flexible, all-solid-state supercapacitors.

Booming Development of Group IV–VI Semiconductors: Fresh Blood of 2D Family

“…Most employed solvothermal methods for synthesizing GIVMCs can summarized by the following procedure: Sn‐halogenides (Cl used mostly) + varied chalcogenide precursors, as shown in Figure 3 a 97, 117, 119, 140, 141, 144, 145, 146, 147. Usually the selection of chalcogenides and the combination of ligands can play crucial roles in determining the morphology, sizes, yield and crystal phases of the as‐synthesis products.…”

“…In general, GIVMCs have been classified into two groups according to their chemical compositions: MX (SiC,89 SiS,90 GeS,91, 92 GeSe,93, 94, 95, 96 SnS,97, 98, 99 SnSe,100, 101, 102, 103, 104, 105, 106, 107, 108 SnTe,109, 110) and MX 2 (GeS 2 ,111 GeSe 2 ,112, 113, 114, 115 SnS 2 ,72, 116, 117, 118 SnSe 2 73, 119, 120, 121, 122, 123, 124, 125). In this part, some typical GIVMCs are presented in Table 1 .…”

Two-Dimensional Disorder in Black Phosphorus and Monochalcogenide Monolayers

“…Monolayers of layered orthorhombic materials [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] can become disordered at room temperature.…”

Transparent, conductive solution processed spincast 2D Ti2CTx (MXene) films

“…Since the discovery of single-layered graphene and its remarkable properties, there has been a groundswell of interest in two-dimensional, 2D, materials [1][2][3][4][5][6][7][8][9][10][11]. The desirable optical and electronic behavior resulting from reduced dimensionality is even further enriched by the opportunity for co-assembly of different 2D materialtypes to form novel heterojunctions [12].…”