Three classes (carbides, nitrides and oxides) of nanoscaled early-transition-metal catalysts have been proposed to replace the expensive Pt catalyst as counter electrodes (CEs) in dye-sensitized solar cells (DSCs). Of these catalysts, Cr(3)C(2), CrN, VC(N), VN, TiC, TiC(N), TiN, and V(2)O(3) all showed excellent catalytic activity for the reduction of I(3)(-) to I(-) in the electrolyte. Further, VC embedded in mesoporous carbon (VC-MC) was prepared through in situ synthesis. The I(3)(-)/I(-) DSC based on the VC-MC CE reached a high power conversion efficiency (PCE) of 7.63%, comparable to the photovoltaic performance of the DSC using a Pt CE (7.50%). In addition, the carbide catalysts demonstrated catalytic activity higher than that of Pt for the regeneration of a new organic redox couple of T(2)/T(-). The T(2)/T(-) DSCs using TiC and VC-MC CEs showed PCEs of 4.96 and 5.15%, much higher than that of the DSC using a Pt CE (3.66%). This work expands the list of potential CE catalysts, which can help reduce the cost of DSCs and thereby encourage their fundamental research and commercial application.
Sunny prospects for renewable energy: Molybdenum and tungsten carbides embedded in ordered nanomesoporous carbon materials as well as Mo2C and WC are proposed as alternatives to the expensive platinum counter electrode (Pt CE). The preparation of the CEs was optimized, and the dye‐sensitized solar cells (DSCs; see picture) equipped with these CEs show a higher energy conversion efficiency than those devices with a Pt CE.
Tungsten dioxide (WO(2)) nanorods were synthesized, which showed excellent catalytic activity for the reduction of triiodide to iodide. The dye-sensitized solar cell (DSC) using WO(2) as a counter electrode (CE) reached a high energy conversion efficiency of 7.25%, which can match the performance of the DSC based on a Pt CE.
Molybdenum sulfide (MoS(2)) and tungsten sulfide (WS(2)) are proposed as counter electrode (CE) catalysts in a I(3)(-)/I(-) and T(2)/T(-) based dye-sensitized solar cells (DSCs) system. The I(3)(-)/I(-) based DSCs using MoS(2) and WS(2) CEs achieved power conversion efficiencies of 7.59% and 7.73%, respectively.
Sun sans Pt: This Minireview summarizes the development of platinum‐free catalysts for use as counter electrodes in dye‐sensitized solar cells. These catalysts comprise various metals, carbon materials, conductive polymers, and inorganic materials (transition metal carbides, nitrides, oxides, sulfides, and phosphides). The research work reported so far highlights the importance of a proper match between counter electrode catalyst and redox couple.
To realize long-term developments
and practical application of
the dye-sensitized solar cells (DSCs) requires a robust increase of
the power conversion efficiency (PCE) and a significant decrease of
the production cost. Fortunately, a new record PCE value of 12.3%
was achieved by using cobalt-based redox couples combined with organic
dye. Evidently, dye design is the key path to improve the PCE, while
developing low cost counter electrode (CE) catalysts is one of the
promising paths to reduce the production cost of DSCs by replacing
the expensive Pt CE. In this article, we review the recent progress
of CE catalysts involving Pt, carbon materials, inorganic materials,
multiple compounds, polymers, and composites. We discuss the advantages
and disadvantages of each catalyst and put forward ideas for designing
new CE catalysts in future research for DSCs and other application
fields.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.