An Interconnected Ternary MIn₂S₄ (M=Fe, Co, Ni) Thiospinel Nanosheet Array: A Type of Efficient Platinum‐Free Counter Electrode for Dye‐Sensitized Solar Cells

Abstract

The ternary iron‐group thiospinels of metal diindium sulfides (MIn2S4, M=Fe, Co, Ni) with a vertically aligned nanosheet array structure are fabricated through an in situ solvothermal method on F‐doped tin oxide (FTO) substrates, which are employed as one type of platinum (Pt)‐free counter electrodes (CEs) in structure‐dependent dye‐sensitized solar cells (DSSCs). A DSSC assembled with ternary CoIn2S4 CE achieves an photoelectric conversion efficiency (PCE) of 8.83 %, outperforming than that of FeIn2S4 (7.18 %) and NiIn2S4 (8.27 %) CEs under full sunlight illumination (100 mW cm−2, AM 1.5 G), which is also comparable with that of the Pt CE (8.19 %). Putting aside that the interconnected nanosheet array provides fast electron transfer and electrolyte diffusion channels, the highest PCE of CoIn2S4 based DSSC results from its largest specific surface area (144.07 m2 g−1), providing abundant active sites and the largest electron injection efficiency from CE to electrolyte.

High-Efficiency Dye-Sensitized Solar Cells Based on Kesterite Cu2ZnSnSe4 Inlaid on a Flexible Carbon Fabric Composite Counter Electrode

“…As a core component in dye-sensitized solar cells (DSSCs), the cathode should possess two basic characteristics of high conductivity and catalytic activity toward I – /I 3 – redox couple, responsible for transfer of the electrons from the external circuit to the redox electrolyte and then catalysis of the reduction of the redox species. − In recent research related to DSSCs, especially in counter electrodes (CEs), many studies were devoted to acquire high-efficiency and long-term stable DSSC devices based on Pt-free CEs. Therefore, several feasible approaches have been developed, such as (1) choosing alternative carbon, , conductive polymer, and inorganic transition-metal compound (TMC) catalytic materials − and (2) incorporating a TMC or conductive polymer with carbon-based materials, for instance, carbon fibers, carbon nanotubes, , graphene, reduced graphene oxide, , carbon black, and carbon fabric (CF). − CF, having benefits of large exposed area, high-conductivity, flexibility, stability, lightweight, and good corrosion resistance toward electrolytes, has been generally applied to flexible and all-weather energy devices, such as supercapacitors, lithium-ion batteries, and DSSCs.…”

CoSe2/N-Doped Carbon Hybrid Derived from ZIF-67 as High-Efficiency Counter Electrode for Dye-Sensitized Solar Cells

“…To date, Pt as the state-of-the-art catalyst is still efficient for the reduction of I 3 – in DSSCs, but it suffers from an expensive price, which hampers its extensive application. To further improve the photoelectric conversion efficiency (PCE) and reduce cost, a general consensus has been reached to develop low-cost and efficient electrocatalysts to replace the conventional Pt. , …”

Generalized Synthesis of Ternary Sulfide Hollow Structures with Enhanced Photocatalytic Performance for Degradation and Hydrogen Evolution

“…Promising as the materials are, semiconductor ternary chalcogenide compounds AB m C n (A = Zn, Cd, Cu, Ag, etc. ; B = Al, Ga, In; C = S, Se, Te) with chalcopyrite structures have been receiving increasing attention owing to their potential applications in charge storage, , thermoelectricity, photocatalysis, − and so on. Over the past decades, considerable efforts have been devoted to the preparation of these ternary chalcogenide materials with various morphologies.…”