Carbon nanotubes and graphene as counter electrodes in dye-sensitized solar cells

Résumé

Abstract Addressing the global demand for cost-effective and sustainable energy sources, dye-sensitized solar cells (DSSCs) have emerged as a promising alternative to conventional silicon-based photovoltaics. However, the use of platinum which is a rare and expensive counter electrode (CE) hinders the widespread application of DSSCs, necessitating the use of cheap, abundant, and efficient materials. The review therefore focuses on carbon-based nanomaterials specifically carbon nanotubes (CNTs) and graphene as CEs in DSSCs. The CE plays a vital role in regenerating the redox couple, and its charge transfer resistance (Rct) should ideally be 1 Ω cm² for optimal performance. Carbon nanotubes comprising single-walled carbon nanotubes (SWCNTs), double-walled carbon nanotubes (DWCNTs), and multiwalled carbon nanotubes (MWCNTs) are mainly prepared by chemical vapor deposition (CVD). The SWCNTs have achieved an efficiency of 7.79%, comparable to platinum electrodes, and this was due to the morphology, which influenced the redox mediator regeneration but also reduced the Rct. In addition, graphene with high transparency (97.7%), large specific surface area (2630 m2 g− 1), excellent thermal conductivity (3000 W m− 1 K− 1), and good carrier mobility properties (10,000 cm2 V− 1 S− 1) have also been applied. In this, the Graphene nanosheets demonstrated a 6.81% efficiency, comparable to platinum (7.59%) due to a high open circuit voltage (Voc), which accounts for the reduction of iodide/triiodide redox couple. Lastly, the Graphene nanoplatelets demonstrated a 9.3% efficiency comparable to that of Platinum 7.53% due to low charge transfer resistance, high electrocatalytic activity, and good fill factor.

Citer ce document

Accès au document

Texte intégral en lecture en ligne, réservé aux abonnés SPHAERO et aux membres de l'institution. Se connecter

Auteur(s)

Statistiques

Consultations : 1

Téléchargements : 0