All-Carbon Electrodes for Flexible Solar Cells

Abstract

Abstract:Transparent electrodes based on carbon nanomaterials have recently emerged as new alternatives to indium tin oxide (ITO) or noble metal in organic photovoltaics (OPVs) due to their attractive advantages, such as long-term stability, environmental friendliness, high conductivity, and low cost. However, it is still a challenge to apply all-carbon electrodes in OPVs. Here, we report our efforts to develop all-carbon electrodes in organic solar cells fabricated with different carbon-based materials, including carbon nanotubes (CNTs) and graphene films synthesized by chemical vapor deposition (CVD). Flexible and semitransparent solar cells with all-carbon electrodes are successfully fabricated. The best power conversion efficiency achieved for the devices with all-carbon electrodes is 0.63%, comparable to the reported performance of OPVs using pristine CVD graphene films as anodes on rigid substrates (glass). Moreover, the current densities of as-obtained devices are comparable to those assembled with all-carbon active layers and standard electrodes (e.g., ITO and metal), which indicates that the all-carbon electrodes made of CNT and graphene films are suitably effective for carrier collection and extraction. Our results present the feasibility and potential of applying all-carbon electrodes based on graphitic nanomaterials in next-generation carbon-based photovoltaics.

Near‐Infrared‐Transparent Perovskite Solar Cells and Perovskite‐Based Tandem Photovoltaics

“…Nevertheless, due to their excellent flexibility and robust nature, the carbon‐based electrodes are promising candidates for the fabrication of flexible PSCs. [ 150 ]…”

Organic solar cells: Current perspectives on graphene‐based materials for electrodes, electron acceptors and interfacial layers

“…[169][170][171][172] Furthermore, ITO has limitations arising from its instability in basic or acidic environments, vulnerability to ion diffusion into polymer layers, rigidity and fragility, which inhibit the use on flexible substrates, and also highquality ITO is deposited using expensive and complicated vacuum techniques. 120,123 Hence, there has been a fieldwide push to find suitable alternatives with a low-cost but similar performance to ITO, of which graphene is a potential candidate due to its high optical transmittance, high electrical conductivity, flexibility, elemental abundance, large specific surface area and ability to facilitate hole and/or electron transfer along its 2D surface. [173][174][175] In addition, graphene plays a vital role in protecting the OSCs against environmental degradation owing to its 2D packed network, which promotes long-term stability.…”

“…Recently, all-carbon-based transparent conducting electrodes have materialized as new replacements for ITO and metal electrodes in OSCs due to their merit of low- cost, mechanical flexibility, high carrier mobility, longterm stability and environmental friendliness. 120,123 However, realization of scalable all-graphene electrode-based devices still remains a challenging task owing to their relatively poor performance, stability and reproducibility. 123 As a response to this anticipated demand, Liu et al 120 fabricated semi-transparent OSCs that employed allgraphene electrodes, as illustrated in Figure 9.…”

Recent advances in fiber-shaped and planar-shaped textile solar cells

“…Recently, scientists have carried out significant research and development efforts in order to improve the performance and the stability of flexible solar cells. [43][44][45][46][47][48][49][50][51][52][53][54][55][56][57][58][59][60][61] Their photoactive materials should be able to generate high power conversion efficiencies (PCE) while having at the same time excellent tolerance towards mechanical bending and stretching stress. 62 However, despite the progress of the latest years, flexible solar cells can still only endure a limited bending radius, ultimately limiting their applicability in flexible products, such as cases where formability, pliability, foldability, and wearability are requested.…”