Topic
Stamping
About: Stamping is a research topic. Over the lifetime, 22501 publications have been published within this topic receiving 83554 citations.
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TL;DR: In this article, a novel approach for a fast phase transition of FAPbI3 (FA = formamidinium) at low-temperature and the effective removal of interfacial recombination was reported.
Abstract: We report a novel approach for a fast phase transition of FAPbI3 (FA = formamidinium) at low-temperature and the effective removal of interfacial recombination in MAPbI3 (MA = methylammonium). This method also allows for printing (patterning) of the perovskite on a desired area. The pre-annealed MAPbI3 and δ-phase FAPbI3 films were prepared by spin-coating DMSO and a polar aprotic solvent admixed precursor solution at 65 °C and 100 °C for about 1 min, respectively, to form adduct films containing DMSO. Two films were sandwiched without pressure by a method called bifacial stamping, and annealed at 100 °C for 9 min, which resulted in complete δ → α phase transition of FAPbI3 and led to a power conversion efficiency (PCE) of 18.34%. The stamped MAPbI3 demonstrated a PCE of 20.18% that was much higher than the conventionally annealed MAPbI3 (∼17.4%) mainly due to a much higher fill factor and open-circuit voltage. Optical and structural studies revealed that DMSO-mediated ion exchange plays a vital role in the phase transition of FAPbI3 and the surface modification of MAPbI3. Theoretical calculation results further support the role of DMSO in the phase transition at low temperature. Stamping was applied to EAPbI3 (EA = ethylammonium), where photoinactive yellow EAPbI3 changed to photoactive EAPbI3 with a PCE of 13.02% after stamping with MAPbI3. The DMSO-mediated EA/MA ion exchange reaction during the stamping process created a new layer having a gradient solid solution of EAPbI3 and MAPbI3, which was responsible for the abnormally high PCE of the EAPbI3 based perovskite solar cell. Facilitated ion transport by a Lewis base (such as DMSO) reservoir in the perovskite adduct film is suggested to be involved in the bifacial stamping procedure.
82 citations
TL;DR: In this article, the effects of important process parameters of these manufacturing processes on the corrosion resistance of metallic bipolar plates made of SS304 were investigated as they were considered to inevitably affect the bipolar plate micro-channel dimensions, surface topography, and hence corrosion resistance.
82 citations
TL;DR: In this paper, the authors used finite element (FE) analysis to model and explain the evolution and distribution of contact pressure over the die radius, throughout the duration of a channel forming process.
81 citations
TL;DR: In this paper, the authors propose the concept of a forming window in strain space that identifies the strains that can be developed safely in a sheet element, bounded by failure limits corresponding to localized necking, shear fracture, and wrinkling.
Abstract: Developments in the numerical modeling of stamping processes and experimental measurements now make it possible to design stamping processes using sound engineering principles. This article shows how experimental and theoretical contributions have led to the concept of a forming window in strain space that identifies the strains that can be developed safely in a sheet element. It is bounded by failure limits corresponding to localized necking, shear fracture, and wrinkling. A robust stamping process is one in which the strains in the part lie well within the forming window. The nature of the window and the influence of material behavior on its shape can be predicted.
81 citations
16 Apr 2007
80 citations