Advancing perovskite solar cell technologies toward their theoretical power conversion efficiency (PCE) requires delicate control over the carrier dynamics throughout the entire device. By controlling the formation of the perovskite layer and careful choices of other materials, we suppressed carrier recombination in the absorber, facilitated carrier injection into the carrier transport layers, and maintained good carrier extraction at the electrodes. When measured via reverse bias scan, cell PCE is typically boosted to 16.6% on average, with the highest efficiency of ~19.3% in a planar geometry without antireflective coating. The fabrication of our perovskite solar cells was conducted in air and from solution at low temperatures, which should simplify manufacturing of large-area perovskite devices that are inexpensive and perform at high levels.

http://science.sciencemag.org/content/sci/345/6196/542.full.pdf

Interface engineering of highly efficient perovskite solar cells

A novel non-fullerene electron acceptor (ITIC) that overcomes some of the shortcomings of fullerene acceptors, for example, weak absorption in the visible spectral region and limited energy-level variability, is designed and synthesized. Fullerene-free polymer solar cells (PSCs) based on the ITIC acceptor are demonstrated to exhibit power conversion effi ciencies of up to 6.8%, a record for fullerene-free PSCs.

An electron acceptor challenging fullerenes for efficient polymer solar cells.

Recent Advances in Bulk Heterojunction Polymer Solar Cells

Thank you for reading numerical heat transfer and fluid flow. Maybe you have knowledge that, people have search numerous times for their favorite books like this numerical heat transfer and fluid flow, but end up in infectious downloads. Rather than reading a good book with a cup of coffee in the afternoon, instead they cope with some malicious virus inside their computer. numerical heat transfer and fluid flow is available in our digital library an online access to it is set as public so you can get it instantly. Our books collection spans in multiple countries, allowing you to get the most less latency time to download any of our books like this one. Merely said, the numerical heat transfer and fluid flow is universally compatible with any devices to read.

Numerical Heat Transfer And Fluid Flow

Perovskite quantum wells yield highly efficient LEDs spanning the visible and near-infrared.

/pdf/perovskite-light-emitting-diodes-based-on-solution-processed-1i56kycdls.pdf

Perovskite light-emitting diodes based on solution-processed self-organized multiple quantum wells

A nanoporous stamp for printing a variety of materials is disclosed. The nanoporous stamp may include a substrate and an array of carbon nanotubes disposed on and attached to the substrate. The array of carbon nanotubes can have an etched top surface and a wettable, nanoporous structure, and may include a coating thereon. The nanoporous stamp can be used in a variety of printing applications, and can print, among other things, colloidal and non-colloidal inks on a variety of substrates with a high degree of accuracy and fidelity.

Nanoporous stamp for flexographic printing

Stimuli responsive optical polymers through omnidirectional and reconfigurable porosity

/pdf/the-synthesis-doping-and-characterization-of-graphene-films-1nrgb6q0zd.pdf

The synthesis, doping, and characterization of graphene films

Shape memory polymers (SMP) have been extensively implemented for applications ranging from biomedical devices and soft robotics to deployable structures. However, these materials mostly rely on heat for shape recovery and programming. Here, we introduce a new class of smart SMPs with pressure-responsive characteristics based on dynamic porosity–an ability to configure a pore size within a solid– that allows for optical monitoring of the stimuli. Introducing pores in a structure reduces the relative density of the material and introduces interfaces resulting in a reduction in optical transparency of the bulk through light scattering. We show that utilizing the dynamic porosity, a macroporous film transitions instantly from an optically opaque (25% transmittance) to a transparent (96% transmittance) state by applying an out-of-plane contact pressure of 3.8 MPa at room temperature. The new SMP also presents an anomalous ‘cold’ shape recovery of the pressure-activated films through repeated in-plane stretching that renucleates the pores and transitions the material back to the initially opaque state. The presented concept ushers a new class of responsive materials that interlace optical sensitivity features with micro- and nanoscale material deformations, establishing new research opportunities in the field of SMPs.

Visual stress sensing using dynamic porosity in shape memory thermoplastic elastomers

Electroemulsification methods use electrohydrodynamic (EHD) forces to manipulate fluids and droplets for emulsion formation. Here, a top-down method is presented using a contactless corona discharge for simultaneous emulsion formation and its pumping/collection. The corona discharge forms using a sharp conductive electrode connected to a high-voltage source that ionizes water vapor droplets (formed by a humidifier) and creates an ionic wind (electroconvection), dragging them into an oil medium. The nonuniform electric field induced by the corona discharge also drives the motion of the oil medium via an EHD pumping effect utilizing a modulated bottom electrode geometry. By these two effects, this contactless method enables the immersion of the water droplets into the moving oil medium, continuously forming a water-in-oil (W/O) emulsion. The impact of corona discharge voltage, vertical and horizontal distances between the two electrodes, and depth of the silicone oil on sizes of the formed emulsions is studied. This is a low-cost and contactless process enabling the continuous formation of the W/O emulsions.

https://pubs.acs.org/doi/pdf/10.1021/acsomega.1c06765

Hossein Sojoudi

Papers

Nanoporous stamp for flexographic printing

Stimuli responsive optical polymers through omnidirectional and reconfigurable porosity

The synthesis, doping, and characterization of graphene films

Visual stress sensing using dynamic porosity in shape memory thermoplastic elastomers

Contactless Method of Emulsion Formation Using Corona Discharge