Electrocatalytic properties of iron chalcogenides as low-cost counter electrode materials for dye-sensitized solar cells

Abstract

Developing cost-effective and highly electrocatalytic Pt-free counter electrode (CE) materials for triiodide reduction has become a major interest for dye-sensitized solar cells (DSCs). In a heterogeneous catalytic system, iron chalcogenides like FeS 2 and FeSe 2 have demonstrated excellent catalytic activity when serving as CE materials in DSCs. However, theoretical and experimental studies have yet to be conducted to investigate the catalytic activity of iron chalcogenides in energy conversion and storage devices under same condition. In this work, FeS 2 , FeSe 2 , and FeTe 2 were selected as our research object to systematically investigate and compare the regulatory mechanisms of the changes in the catalytic activity of iron chalcogenides. Theoretical research reveals that the iodine adsorption and charge exchange of these three materials occurred efficiently in heterogeneous catalytic systems. Experimental results further show that these three materials exhibited excellent catalytic activities. The conversion efficiencies of the corresponding DSCs are comparable to those of the sputtered Pt CE. This study also provides a method to rationally screen cost-effective and highly efficient catalytic materials for electrocatalysis applications.−

Earth Abundant Silicon Composites as the Electrocatalytic Counter Electrodes for Dye-Sensitized Solar Cells

“…Besides, it can be deduced from this study that the electrocatalytic abilities of these four kinds of silicon-based materials followed the same order of SiSe 2 -5 > Si 3 N 4 -5 > SiS 2 -5 > SiO 2 -1. In accordance with the literature, the electrocatalytic ability of a transition metal compound was reported to be influenced by many complicated factors, including the band structure, ,, the distribution of the density of state, ,, the surface energy, the adsorption energy, ,− etc. ; the information on these factors was often obtained via the density functional theory (DFT) calculation.…”

Metal Selenides as Efficient Counter Electrodes for Dye-Sensitized Solar Cells

“…Among the three morphologies, the 3D hierarchical FeSe 2 nanosheet CE has the lowest R ct and hence the highest PCE . DFT calculations reveal that the intrinsic high catalytic activity of FeSe 2 may originate from its low work function and strong iodine adsorbing capability …”

Photovoltaic Counter Electrodes: An Alternative Approach to Extend Light Absorption Spectra and Enhance Performance of Dye‐Sensitized Solar Cells

“…For amazing conductivity and electrocatalytic ability in DSSCs, Pt has been established to be the most useful counter electrode. Unfortunately, Pt can be corroded and dissolved by iodic electrolyte to form PtI 4 and H 2 PtI 6 . Considering that, it is essential to develop inexpensive, stable and effective CE materials.…”

“…Unfortunately, Pt can be corroded and dissolved by iodic electrolyte to form PtI 4 and H 2 PtI 6 . [6] Considering that, it is essential to develop inexpensive, stable and effective CE materials. Photovoltaic parameters of some materials as CEs are summarized in Table S1.…”