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A spin-coating-free fabrication sequence has been developed for the fabrication of highly efficient organic-inorganic halide perovskite solar cells (PSCs). A novel blow-drying method is demonstrated to be successful in depositing high quality mesoporous TiO2 (mp-TiO2), methylammonium lead halide (CH3NH3PbI3) perovskite and spiro-MeOTAD layers. When combined with compact TiO2 (c-TiO2) deposited by spray pyrolysis which is also a spin-coating-free process, a stabilized power conversion efficiency exceeding 17% can be achieved for the glass/FTO/c-TiO2/mp-TiO2/ CH3NH3PbI3/spiro-MeOTAD/Au device. This is the highest efficiency for PSCs fabricated without the use of spin-coating to our knowledge. This method provides a pathway towards a scalable process for fabricating high-performance, large area and reproducible PSCs.

AbstractConsolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined, and new entries since January 2017 are reviewed.

A simple and scalable interface-layer free monolithic perovskite/silicon tandem has been demonstrated achieving over 20% efficiency on a large area.

AbstractAn insight into the analogies, state‐of‐the‐art technologies, concepts, and prospects under the umbrella of perovskite materials (both inorganic–organic hybrid halide perovskites and ferroelectric perovskites) for future multifunctional energy conversion and storage devices is provided. Often, these are considered entirely different branches of research; however, considering them simultaneously and holistically can provide several new opportunities. Recent advancements have highlighted the potential of hybrid perovskites for high‐efficiency solar cells. The intrinsic polar properties of these materials, including the potential for ferroelectricity, provide additional possibilities for simultaneously exploiting several energy conversion mechanisms such as the piezoelectric, pyroelectric, and thermoelectric effect and electrical energy storage. The presence of these phenomena can support the performance of perovskite solar cells. The energy conversion using these effects (piezo‐, pyro‐, and thermoelectric effect) can also be enhanced by a change in the light intensity. Thus, there lies a range of possibilities for tuning the structural, electronic, optical, and magnetic properties of perovskites to simultaneously harvest energy using more than one mechanism to realize an improved efficiency. This requires a basic understanding of concepts, mechanisms, corresponding material properties, and the underlying physics involved with these effects.

AbstractWe present a simple yet powerful analysis of Suns‐photoluminescence quantum yield measurements that can be used to determine the surface saturation current densities of thin film semiconductors. We apply the method to state‐of‐the‐art polycrystalline perovskite thin films of varying absorber thickness. We show that the non‐radiative bimolecular recombination in these samples originates from the surfaces. To the best of our knowledge, this is the first study to demonstrate and quantify non‐linear (bimolecular) surface recombination in perovskite thin films.

Emerging photovoltaics (PVs), focuses on a variety of applications complementing large scale electricity generation. For instance, organic, dye-sensitized and some perovskite solar cells are considered in building integration, greenhouses, wearable and indoors, thereby motivating research on flexible, transparent, semitransparent, and multi-junction PVs. Nevertheless, it can be very time consuming to find or develop an up-to-date overview over the state-of-the-art performance for these systems and applications. Two important resources for record research cells efficiencies are the National Renewable Energy Laboratory chart and the efficiency tables compiled biannually by Martin Green and colleagues. Both publications provide an effective coverage over the established technologies, bridging research and industry. An alternative approach is proposed here summarizing the best reports in the diverse research subjects for emerging PVs. Best performance parameters are provided as a function of the photovoltaic bandgap energy for each technology and application, and are put into perspective using, e.g., the Shockley-Queisser limit. In all cases, the reported data correspond to published and/or properly described certified results, with enough details provided for prospective data reproduction. Additionally, the stability test energy yield (STEY) is included as an analysis parameter among state-of-the-art emerging PVs.

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