Enhanced Performance of Carbon–Selenide Composite with La0.9Ce0.1NiO3 Perovskite Oxide for Outstanding Counter Electrodes in Platinum-Free Dye-Sensitized Solar Cells

Abstract

For large-scale applications, dye-sensitized solar cells (DSSCs) require the replacement of the scarce platinum (Pt)-based counter electrode (CE) with efficient and cheap alternatives. In this respect, low-cost perovskite oxides (ABO3) have been introduced as promising additives to composite-based CEs in Pt-free DSSCs. Herein, we synthesized composites from La0.9Ce0.1NiO3 (L) perovskite oxide and functionalized-multiwall-carbon-nanotubes wrapped in selenides derived from metal-organic-frameworks (f-MWCNT-ZnSe-CoSe2, “F”). L and F were then mixed with carbon black (CB) in different mass ratios to prepare L@CB, F@CB, and L@F@CB composites. The electrochemical analysis revealed that the L@F@CB composite with a mass ratio of 1.5:3:1.5 exhibits better electrocatalytic activity than Pt. In addition, the related DSSC reached a better PCE of 7.49% compared to its Pt-based counterpart (7.09%). This improved performance is the result of the increase in the oxygen vacancy by L due to the replacement of La with Ce in its structure, leading to more active sites in the L@F@CB composites. Moreover, the F@CB composite favors the contribution to the high electrical conductivity of the hybrid carbon nanotube–carbon black, which also offers good stability to the L@F@CB CE by not showing any obvious change in morphology and peak-to-peak separation even after 100 cyclic voltammetry cycles. Consequently, the corresponding L@F@CB-based device achieved enhanced stability. Our work demonstrates that L@F@CB composites with a low cost are excellent alternatives to Pt CE in DSSCs.

A Density Functional Theory Study of the Physico-Chemical Properties of Alkali Metal Titanate Perovskites for Solar Cell Applications

“…Based on the optical properties of the electronic structures, NaTiO 3 is considered the preferred candidate among the investigated titanate-based perovskite structures as CTL and TCE in the PSCs and Per-SCs. While no reports exist on the use of NaTiO 3 as a CTL or TCE, several studies have explored other perovskite oxides with high transparency in the solar spectrum for these functions [30,34,[125][126][127]. Our findings indicate the potential suitability of NaTiO 3 for similar applications, suggesting the need for further experimental validation.…”

Multifunctional Structure-Modified Quaternary Compounds Co9Se8–CuSe2–WSe2 Mixed with MWCNT as a Counter Electrode Material for Dye-Sensitized Solar Cells

“…Carbon-based materials such as MWCNT and graphene have been gaining attention due to their high electrical conductivity and large surface area. − Several research papers have reported to utilize these materials for the CE of DSSCs. − For example, Tapa et al synthesized a metal–organic framework (MOF) derived selenide from a reduced graphene oxide (rGO)/structured zeolitic imidazolate framework (ZIF) . The resulting material took the form of porous nanowires enveloped in a carbon matrix and was mixed with polystyrenesulfonate-doped poly­(3,4-ethylenedioxythiophene) (PEDOT/PSS) as CE material of DSSCs.…”