Gram‐Scale Synthesized Two‐Dimensional VSe₂ and SnSe₂ for Ultrahigh Electrocatalytic Sulfion Recycling

Abstract

properties [4][5][6][7] and are also demonstrating broad application potentials in the energyrelated fields, [8][9][10][11][12][13][14][15][16][17][18] electronic devices, [19][20][21][22] and molecular chemistries. [23,24] Notably, the scalable synthesis of 2D TMDCs is an essential prerequisite, and considerable efforts have also been made, including mechanical/chemical exfoliation, [25,26] wet chemical synthesis, [27][28][29][30] ion intercalation, [31][32][33][34] and chemical vapor deposition (CVD). [35][36][37][38] However, some bottlenecks have been proposed for these approaches, such as complex growth processes, highcost, low-yield, and environmental pollution. In this regard, it is highly desirable to develop a scalable and high-efficiency method to synthesize 2D TMDCs with a high yield.As a kind of high-efficient and clean secondary energy, H 2 is emerging as a splendid alternative for fossil fuels due to its high energy density and zero carbon emission. [39] Recent years have witnessed revolutionary progress in exploiting electrocatalysts for hydrogen/oxygen evolution reactions (HER/OER). [3,40] Nevertheless, in consideration of the incompatible activity over different pH ranges, the excellent HER and OER performances are not obtained in the same electrolytes for the most of reported electrocatalysts. [41] In addition, the development of OER is sluggish and consumes a mass of electricity input producing relatively low-value products. [42] It is thus highly urgent to explore new electrocatalysts for reducing electricity consumption and enhancing the H 2 evolution. Interestingly, the sulfion oxidation reaction (SOR) is much more thermodynamically favorable than OER in view of the fact that the S 2− is more prone to offer electrons. [43] Therefore, the electrocatalytic SOR should be investigated as the alternative of OER for the H 2 evolution by coupling with cathodic HER. Moreover, as a kind of toxic by-product in the industrial production, the S 2− should be removed or recycled. [44] However, the SOR performances of most of the reported electrocatalysts are still unsatisfactory.To tackle such issues, we design a high-throughput, highyield, and low-temperature strategy for the direct synthesis of 2D VSe 2 nanosheets and SnSe 2 nanoflowers, respectively. This provides us with an opportunity for the exploration of energy applications. In particular, a plentiful of wrinkles and unique hierarchical structures are observed in ultrathin VSe 2 nanosheets and SnSe 2 nanoflowers, respectively, which offerThe electrocatalytic sulfion (S 2− ) recycling and hydrogen (H 2 ) evolution play indispensable roles in converting waste into sustainable energy and boosting hydrogen economy. However, the development of such promising technologies is hindered by the lack of electrocatalysts with low-cost, high-efficient, and robust stability. 2D VSe 2 and SnSe 2 hold great application potentials in the energy-related fields yet face daunting challenges in terms of large-scale synthesis. Herein, a gram-scale and high-yield strate...

Solution-phase synthesis of group 3–5 transition metal chalcogenide inorganic nanomaterials

“…, 40 mmol for VSe 2 ) was described. 57,59 Unfortunately, reaction yields are infrequently reported in descriptions of nanocrystal syntheses; however, when given, mass yields for the reactions described here are mostly moderate to good (∼40–80%). 31,57,59,67 For example, we reported a yield of approximately 48% for the synthesis of BaZrS 3 nanocrystals.…”

“…57,59 Unfortunately, reaction yields are infrequently reported in descriptions of nanocrystal syntheses; however, when given, mass yields for the reactions described here are mostly moderate to good (∼40–80%). 31,57,59,67 For example, we reported a yield of approximately 48% for the synthesis of BaZrS 3 nanocrystals. 3 Although there is room for improvement, this suggests that reaction yield may not be an inherently limiting factor in the development of early transition metal chalcogenide nanomaterial synthesis.…”

“…Solution-synthesized VSe 2 and TaS 2 nanomaterials have been investigated as electrocatalysts for the hydrogen evolution reaction (HER). 49,57,59,61,72 For example, Cao et al demonstrated that single-layer VSe 2 nanosheets prepared in oleylamine exhibited significantly improved electrocatalytic performance (lower overpotential for a given current density and lower Tafel slope) relative to multilayer nanosheets; they further demonstrated that removal of the native long-chain ligands (which they accomplished by oxygen plasma exposure, OPE) was critical to catalytic performance (Fig. 14(B)).…”

“…49,61 Solutionsynthesized VSe 2 nanosheets have also shown excellent activity in electrocatalytic sulfide oxidation, outperforming previously reported materials. 59 Nb 2 Se 9 nanocrystals have been demonstrated as electrocatalysts for the oxygen reduction reaction, with morphology-dependent onset potentials and Tafel slopes; nanowires showed considerably superior performance relative to nanosheets, which was attributed to the different catalytic competence of different nanocrystal facets and edges. 67 NbSe 2 and Nb 2 Se 9 nanocrystals have also been applied as counterelectrodes in dye-sensitized solar cells, where they act to catalyse the reduction of I 3 À to I À ; once again, morphologies with higher surface area tended to show superior performance.…”

“…9(F)). 59 Additionally, the Radu group incorporated dodecanethiol as an additional solvent and used a lower reaction temperature (250 °C) to produce highly crystalline VSe 2 nanosheets which were used as precursors for ternary materials ( vide infra ; Fig. 9(E)).…”