Rational screening low-cost counter electrodes for dye-sensitized solar cells

Abstract

Dye-sensitized solar cells have attracted intense research attention owing to their ease of fabrication, cost-effectiveness and high efficiency in converting solar energy. Noble platinum is generally used as catalytic counter electrode for redox mediators in electrolyte solution. Unfortunately, platinum is expensive and non-sustainable for long-term applications. Therefore, researchers are facing with the challenge of developing low-cost and earthabundant alternatives. So far, rational screening of non-platinum counter electrodes has been hamstrung by the lack of understanding about the electrocatalytic process of redox mediators on various counter electrodes. Here, using first-principle quantum chemical calculations, we studied the electrocatalytic process of redox mediators and predicted electrocatalytic activity of potential semiconductor counter electrodes. On the basis of theoretical predictions, we successfully used rust (a-Fe 2 O 3 ) as a new counter electrode catalyst, which demonstrates promising electrocatalytic activity towards triiodide reduction at a rate comparable to platinum.

Hydrothermal growth of MoS2/Co3S4 composites as efficient Pt-free counter electrodes for dye-sensitized solar cells

“…Based on the slab band quantum computational principle, the calculated catalytic activity of CoxSy is analogous to platinum due to the corresponding surface structure which creates electron transfer pathways for reduction kinetics [28]. Therefore, cobalt sulfides could act as the catalyst for triiodide reduction in DSSCs.…”

WB crystals with oxidized surface as counter electrode in dye-sensitized solar cells

“…Therefore, the research of DSSCs is still significant for developing low-cost solar cells. The search for highly active and affordable counter electrode materials to replace the widely used but high-cost noble metal Pt in DSSCs has been a focus in both scientific and industrial areas [8][9][10][11][12]. The excellent performance of Pt based counter electrode is attributed to both the high catalytic activity of Pt in inducing triiodide reduction reaction and its high electrical conductivity [8], which enable fast electron transfer from the counter electrode to electrolyte in the cell.…”

“…The search for highly active and affordable counter electrode materials to replace the widely used but high-cost noble metal Pt in DSSCs has been a focus in both scientific and industrial areas [8][9][10][11][12]. The excellent performance of Pt based counter electrode is attributed to both the high catalytic activity of Pt in inducing triiodide reduction reaction and its high electrical conductivity [8], which enable fast electron transfer from the counter electrode to electrolyte in the cell. In the past years, various earth-abundant materials including carbon [13][14][15][16], transition metal sulphides [17][18][19], carbides [20,21], nitrides [22,23], phosphides [24,25] and oxides [26][27][28][29][30][31][32][33][34][35] have been explored and shown a great potential as counter electrode materials.…”

Nanofabrication of uniform and stabilizer-free self-assembled platinum monolayers as counter electrodes for dye-sensitized solar cells

“…Recent studies have focused efforts on replacing Pt with other materials as inexpensive alternatives for CEs. [9][10][11][12][13][14][15][16][17][18] Although some inorganic compounds possess catalytic activity similar to that of Pt, a deposition of thick films and nanostructures imbedded in a threedimensional matrix are typically required to achieve that similar catalytic performance, which result in an adhesion issue and opaque behavior of the CE. 13,14 Pt continues to be considered the most adequate material for CEs, and the most promising devices with record power conversion efficiencies contain platinized CEs.…”