More Like this

1. Hybrid Perovskite Photovoltaic Devices: Properties, Architecture, and Fabrication Methods

   https://doi.org/10.1002/ente.201600486  

   Al‐Dainy, Gailan A. ; Bourdo, Shawn E. ; Saini, Viney ; Berry, Brian C. ; Biris, Alexandru S. ( February 2017 , Energy Technology)

   As the need for green energy increases, particularly solar energy, perovskite‐based devices have become a promising alternative to more complex, costly semiconductor‐based photovoltaic devices. The major advantage of perovskite‐based devices is their relatively facile fabrication as a thin film at fairly low temperatures and their tunable optoelectronic properties. The chemical composition of perovskite structures, solvent and heat treatments used in processing, additives, and deposition methods produce films with different morphologies. Their ability to be used with other organic and inorganic subcells makes them a useful component for an efficient, cost‐effective approach to harvest solar energy. This review presents some of the latest approaches and considerations for the fabrication, architecture, and performance of perovskite‐based solar cells. Various perovskite device architectures are discussed, as well as the effects of environmental conditions on performance and degradation.

    

   more » « less
2. Enhanced Charge Transport in Hybrid Perovskite Field‐Effect Transistors via Microstructure Control

   https://doi.org/10.1002/aelm.201800316  

   Zeidell, Andrew M. ; Tyznik, Colin ; Jennings, Laura ; Zhang, Chuang ; Lee, Hyunsu ; Guthold, Martin ; Vardeny, Z. Valy ; Jurchescu, Oana D. ( September 2018 , Advanced Electronic Materials)

   Hybrid organic–inorganic perovskites have recently gained immense attention due to their unique optical and electronic properties and low production cost, which make them promising candidates for a wide range of optoelectronic devices. But unlike most other technologies, the breakthroughs witnessed in hybrid perovskite optoelectronics have outgrown the basic understanding of the fundamental material properties. For example, the effectiveness of charge transport in relation to film microstructure and processing has remained elusive. In this study, field‐effect transistors are fabricated and evaluated in order to probe the nature and dynamics of charge transport in thin films of methylammonium lead iodide. A dramatic improvement is shown in the electrical properties upon solvent vapor annealing. The resulting devices exhibit ambipolar transport, with room‐temperature hole and electron mobilities exceeding 10 cm²V⁻¹s⁻¹. The remarkable enhancement in charge carrier mobility is attributed to the increase in the grain size and passivation of grain boundaries via the formation of solvent complexes.

    

   more » « less
3. Contact patterning by laser printing for flexible electronics on paper

   https://doi.org/10.1038/s41528-019-0055-3  

   Harper, Angela F. ; Diemer, Peter J. ; Jurchescu, Oana D. ( June 2019 , npj Flexible Electronics)

   The desire for cost-effective strategies for producing organic electronic devices has led to many new methods for the organic semiconductor layer deposition; however, manufacturing contacts remains an expensive technique due to the high cost of both the materials used and the processing necessary for their patterning. In this work, we present a method for contact deposition and patterning, which overcomes these limitations and allows fabrication of all-printed organic thin-film transistors on paper. The method relies on depositing contacts using aerosol spray and patterning them with a digitally printed mask from an office laser printer, at ambient temperature and pressure. This technique, which we have denoted aerosol spray laser lithography, is cost-effective and extremely versatile in terms of material choice and electrode geometry. As the processing temperature does not exceed 155 °C, it is compatible with a variety of substrates, including plastic or paper. The success of this method marks an opportunity for a rapid, scalable, and low-cost alternative to current electrode-manufacturing techniques for development of flexible, large-area, electronic applications.

    

   more » « less
4. Printable Organic‐Inorganic Nanoscale Multilayer Gate Dielectrics for Thin‐Film Transistors Enabled by a Polymeric Organic Interlayer

   https://doi.org/10.1002/adfm.202005069  

   Chen, Yao ; Zhuang, Xinming ; Goldfine, Elise A. ; Dravid, Vinayak P. ; Bedzyk, Michael J. ; Huang, Wei ; Facchetti, Antonio ; Marks, Tobin J. ( August 2020 , Advanced Functional Materials)

   Here, a new approach to the layer‐by‐layer solution‐processed fabrication of organic/inorganic hybrid self‐assembled nanodielectrics (SANDs) is reported and it is demonstrated that these ultrathin gate dielectric films can be printed. The organic SAND component, named P‐PAE, consists of polarizable π‐electron phosphonic acid‐based units bound to a polymeric backbone. Thus, the new polymeric SAND (PSAND) can be fabricated either by spin‐coating or blade‐coating in air, by alternating P‐PAE, a capping reagent layer, and an ultrathin ZrOx layer. The new PSANDs thickness vary from 6 to 15 nm depending on the number of organic‐ZrOx bilayers, exhibit tunable film thickness, well‐defined nanostructures, large electrical capacitance (up to 558 nF cm⁻²), and good insulating properties (leakage current densities as low as 10⁻⁶A cm⁻²). Organic thin‐film transistors that are fabricated with representative p‐/n‐type organic molecular/polymeric semiconducting materials, function well at low voltages (<3.0 V). Furthermore, flexible TFTs fabricated with PSAND exhibit excellent mechanical flexibility and good stress stability, offering a promising route to low operating voltage flexible electronics. Finally, printable PSANDs are also demonstrated and afford TFTs with electrical properties comparable to those achieved with the spin‐coated PSAND‐based devices.

    

   more » « less
5. Study of disorder in pulsed laser deposited double perovskite oxides by first-principle structure prediction

   https://doi.org/10.1038/s41524-021-00561-1  

   Fertitta, Edoardo ; Das, Sujit ; Banerjee, Debalina ; Ebrahimi, Farbod ; Barraud, Clément ; Du, Kai ; Tian, He ; Pickard, Chris J. ; Weber, Cedric ; Ramesh, Ramamoorthy ; et al ( June 2021 , npj Computational Materials)

   Double perovskite oxides, with generalized formula A₂BB$$^{\prime}$$${}^{\prime }$O₆, attract wide interest due to their multiferroic and charge transfer properties. They offer a wide range of potential applications such as spintronics and electrically tunable devices. However, great practical limitations are encountered, since a spontaneous order of the B-site cations is notoriously hard to achieve. In this joint experimental-theoretical work, we focused on the characterization of double perovskites La₂TiFeO₆and La₂VCuO₆films grown by pulsed laser deposition and interpretation of the observed B-site disorder and partial charge transfer between the B-site ions. A random structure sampling method was used to show that several phases compete due to their corresponding configurational entropy. In order to capture a representative picture of the most relevant competing microstates in realistic experimental conditions, this search included the potential formation of non-stoichiometric phases as well, which could also be directly related to the observed partial charge transfer. We optimized the information encapsulated in the potential energy landscape, captured via structure sampling, by evaluating both enthalpic and entropic terms. These terms were employed as a metric for the competition of different phases. This approach, applied herein specifically to La₂TiFeO₆, highlights the presence of highly entropic phases above the ground state which can explain the disorder observed frequently in the broader class of double perovskite oxides.

    

   more » « less