A Reusable N‐Doped‐Carbon‐Coated Mo₂C Composite Counter Electrode for High‐Efficiency Dye‐Sensitized Solar Cells

Abstract

The design and development of efficient and stable nonprecious-metal-based catalysts for counter electrodes (CEs) in dye-sensitized solar cells (DSSCs) has received a great deal of attention. In this work, molybdenum carbide nanoparticles homogeneously distributed in a nitrogen-rich carbon matrix (Mo C@NC) have been synthesized from inexpensive raw materials (polyoxometalate and dicyandiamide) by a facile one-step solid-phase synthesis method. The novel Mo C@NC hybrid was not only used as a CE in a DSSC, but also showed superior catalytic activity towards I /I as a redox electrolyte. The power conversion efficiency of a DSSC with Mo C@NC as the CE was as high as 6.49 %, comparable to that with Pt (6.38 %). The CE was prepared by a drop-coating method, without the addition of another conductive polymer. Most importantly, the method circumvents the problem of the sample falling off from the fluorine-doped tin oxide (FTO), and the CE could be repeatedly reused with unchanged efficiency. Therefore, it opens the way for the development of platinum-free catalysts with low cost, simple processing, good stability, and high efficiency.

Polyoxometalate‐Derived Multi‐Component X/W2C@X,N‐C (X=Co, Si, Ge, B, and P) Nanoelectrocatalysts for Efficient Triiodide Reduction in Dye‐Sensitized Solar Cells

“…Moreover, the corrosion of Pt in iodide redox electrolyte will seriously weaken the stabilityo ft he solar cells. [5,6] Therefore, the designa nd fabrication of low-cost,h ighly effective, and durable CE catalysts has becomee xtremelyu rgent. [7,8] Over the past decades, various conductive polymers, nanocarbon materials, and transition-metal-based materials have been employed as potentials ubstitutesf or the conventional Pt catalyst in DSSCs.…”

Polyoxometalates‐Based Semi‐flexible Metal‐Semiconductor Triboelectric Nanogenerators for Low Frequency and Small Amplitude Mechanical Energy Harvesting

“…[31][32][33][34][35][36][37][38] In the past ten years, our research team has introduced POMs into dyesensitized solar cells (DSSCs) and proved that POMs are a class of good electronic transmission medium that can store and export electrons quickly. [39][40][41][42][43][44][45][46][47] In addition, we also applied POMs to the electrode materials of the piezoelectric nanogenerator (PENG), a flexible transparent device which can convert mechanical energy into electricity effectively and further confirmed that POMs as good electron transport medium can be used in energy conversion devices. [48] Therefore, we imagine that POMs can be used as a charge transport layer to improve the output performance of metal-semiconductor TENGs, thereby achieving efficient charge transfer and storage in semiconductor friction materials, and making up for the ability of semiconductor materials to transfer and store charges.…”

“…Polyoxometalates (POMs), an effective electronic transmission medium, have the advantages of simple synthesis, low‐cost, redox reversibility and excellent stability [31–38] . In the past ten years, our research team has introduced POMs into dye‐sensitized solar cells (DSSCs) and proved that POMs are a class of good electronic transmission medium that can store and export electrons quickly [39–47] . In addition, we also applied POMs to the electrode materials of the piezoelectric nanogenerator (PENG), a flexible transparent device which can convert mechanical energy into electricity effectively and further confirmed that POMs as good electron transport medium can be used in energy conversion devices [48] .…”

Review on Low‐Cost Counter Electrode Materials for Dye‐Sensitized Solar Cells: Effective Strategy to Improve Photovoltaic Performance

“…Wang et al used polyoxometalate and dicyandiamide as a precursor to synthesis reusable N-doped carbon-coated Mo 2 C (Mo 2 C@NC) composite via simple solid-phase route. [162] More importantly, it can be repeatedly reused without cause performance degradation when Mo 2 C@NC composite is employed as CE materials in DSSCs. [142] Copyright 2014, Wiley-VCH.…”