A broad organic–inorganic series of hybrid metal iodide perovskites with the general formulation AMI3, where A is the methylammonium (CH3NH3+) or formamidinium (HC(NH2)2+) cation and M is Sn (1 and 2) or Pb (3 and 4) are reported. The compounds have been prepared through a variety of synthetic approaches, and the nature of the resulting materials is discussed in terms of their thermal stability and optical and electronic properties. We find that the chemical and physical properties of these materials strongly depend on the preparation method. Single crystal X-ray diffraction analysis of 1–4 classifies the compounds in the perovskite structural family. Structural phase transitions were observed and investigated by temperature-dependent single crystal X-ray diffraction in the 100–400 K range. The charge transport properties of the materials are discussed in conjunction with diffuse reflectance studies in the mid-IR region that display characteristic absorption features. Temperature-dependent studies show a ...

Semiconducting tin and lead iodide perovskites with organic cations: phase transitions, high mobilities, and near-infrared photoluminescent properties.

Since the discovery of highly conducting polyacetylene by Shirakawa, MacDiarmid, and Heeger in 1977, π-conjugated systems have attracted much attention as futuristic materials for the development and production of the next generation of electronics, that is, organic electronics. Conceptually, organic electronics are quite different from conventional inorganic solid state electronics because the structural versatility of organic semiconductors allows for the incorporation of functionality by molecular design. This versatility leads to a new era in the design of electronic devices. To date, the great number of π-conjugated semiconducting materials that have either been discovered or synthesized generate an exciting library of π-conjugated systems for use in organic electronics. 11 However, some key challenges for further advancement remain: the low mobility and stability of organic semiconductors, the lack of knowledge regarding structure property relationships for understanding the fundamental chemical aspects behind the structural design, and realization of desired properties. Organic field-effect transistors (OFETs) are a kind of device consisting of an organic semiconducting layer, a gate insulator layer, and three terminals (drain, source, and gate electrodes). OFETs are not only essential building blocks for the next generation of cheap and flexible organic circuits, but they also provide an important insight into the charge transport of πconjugated systems. Therefore, they act as strong tools for the exploration of the structure property relationships of πconjugated systems, such as parameters of field-effect mobility (μ, the drift velocity of carriers under unit electric field), current on/off ratio (the ratio of the maximum on-state current to the minimum off-state current), and threshold voltage (the minimum gate voltage that is required to turn on the transistor). 17 Since the discovery of OFETs in the 1980s, they have attracted much attention. Research onOFETs includes the discovery, design, and synthesis of π-conjugated systems for OFETs, device optimization, development of applications in radio frequency identification (RFID) tags, flexible displays, electronic papers, sensors, and so forth. It is beyond the scope of this review to cover all aspects of π-conjugated systems; hence, our focus will be on the performance analysis of π-conjugated systems in OFETs. This should make it possible to extract information regarding the fundamental merit of semiconducting π-conjugated materials and capture what is needed for newmaterials and what is the synthesis orientation of newπ-conjugated systems. In fact, for a new science with many practical applications, the field of organic electronics is progressing extremely rapidly. For example, using “organic field effect transistor” or “organic field effect transistors” as the query keywords to search the Web of Science citation database, it is possible to show the distribution of papers over recent years as shown in Figure 1A. It is very clear

Semiconducting π-conjugated systems in field-effect transistors: a material odyssey of organic electronics.

We fabricated a perovskite solar cell that uses a double layer of mesoporous TiO2 and ZrO2 as a scaffold infiltrated with perovskite and does not require a hole-conducting layer. The perovskite was produced by drop-casting a solution of PbI2, methylammonium (MA) iodide, and 5-ammoniumvaleric acid (5-AVA) iodide through a porous carbon film. The 5-AVA templating created mixed-cation perovskite (5-AVA)x(MA)1- xPbI3 crystals with lower defect concentration and better pore filling as well as more complete contact with the TiO2 scaffold, resulting in a longer exciton lifetime and a higher quantum yield for photoinduced charge separation as compared to MAPbI3. The cell achieved a certified power conversion efficiency of 12.8% and was stable for >1000 hours in ambient air under full sunlight.

https://science.sciencemag.org/content/sci/345/6194/295.full.pdf

A hole-conductor-free, fully printable mesoscopic perovskite solar cell with high stability

/pdf/metal-organic-frameworks-and-self-assembled-supramolecular-2xs948xxr9.pdf

Metal–Organic Frameworks and Self-Assembled Supramolecular Coordination Complexes: Comparing and Contrasting the Design, Synthesis, and Functionality of Metal–Organic Materials

Although known since the late 19th century, organic–inorganic perovskites have recently received extraordinary research community attention because of their unique physical properties, which make them promising candidates for application in photovoltaic (PV) and related optoelectronic devices. This review will explore beyond the current focus on three-dimensional (3-D) lead(II) halide perovskites, to highlight the great chemical flexibility and outstanding potential of the broader class of 3-D and lower dimensional organic-based perovskite family for electronic, optical, and energy-based applications as well as fundamental research. The concept of a multifunctional organic–inorganic hybrid, in which the organic and inorganic structural components provide intentional, unique, and hopefully synergistic features to the compound, represents an important contemporary target.

Organic–Inorganic Perovskites: Structural Versatility for Functional Materials Design

Thiacrown ether tetrathiafulvalene derivatives as redox responsive ligands

The motley family of polar compounds (MV) M(X5-xX (x)) based on anionic chains of trans-connected M-(III)(X,X)(6) octahedra (M=Bi, Sb; X, X=Cl, Br, I) and methylviologen (MV) dications

The synthesis of a calix[4]arene derivative bearing pendant tetrathiafulvalene (TTF) units is described. Two electroactive TTF units are linked to the calix[4]arene platform through amide functions for the binding of anions. An X-ray structure of a calixarene–amide–TTF assembly existing in a cone conformation is provided. The binding ability of this receptor for H2PO4− is shown by 1H-NMR and electrochemical studies (cyclic voltammetry).

A calixarene-amide-tetrathiafulvalene assembly for the electrochemical detection of anions

Syntheses of the first bis-calixarenes systems bridged by a tetrathiafulvalene (TTF) framework 5a,b have been carried out in good yields through triethyl phosphite-mediated dechalcogenation−dimerizations of the corresponding 1,3-dithiole-2-(thi)ones 3 or 4. X-ray structures of the calix[4]arene−TTF−calix[4]arene assembly 5b and of the calix[4]arene−thione intermediate 3b are analyzed and confirm the cone conformations adopted by the calix[4]arene parts, as it is also observed by 1H NMR analysis of these systems. The solid-state organization in 5b leads to alternate layers of calixarene and TTF units. The cyclic voltammograms of 5a,b show as expected a two-step redox behavior but display a CV deformation for the second redox process.

Bis-calix[4]arenes bridged by an electroactive tetrathiafulvalene unit.

The alpha1-(Br-(CH(2))(2)-NH(3))(2)PbI(4) hybrid perovskite undergoes a solid-state transformation, that is, the reaction between the organic cations and the perovskite layers to give the new hybrid perovskite (Br-(CH(2))(2)-NH(3))(2-x)(I-(CH(2))(2)-NH(3))(x)PbBr(x)I(4-x), based on mixed halide inorganic layers. This transformation has been followed by a conventional powder X-ray diffraction system equipped with a super speed detector, and both solid-state (13)C NMR and ESI/MS measurements have been adopted in the estimation of the rate of halide substitution. The first reaction step leads to the special composition of x approximately 1 (A phase), while the complete substitution is not achieved even at elevated temperature (x(max) approximately 1.85 (B phase)). This unprecedented solid-state reaction between organic and inorganic components of a hybrid perovskite can be considered as a completely new strategy to achieve interesting hybrid perovskites.

Nicolas Mercier

Papers

Thiacrown ether tetrathiafulvalene derivatives as redox responsive ligands

The motley family of polar compounds (MV) M(X5-xX (x)) based on anionic chains of trans-connected M-(III)(X,X)(6) octahedra (M=Bi, Sb; X, X=Cl, Br, I) and methylviologen (MV) dications

A calixarene-amide-tetrathiafulvalene assembly for the electrochemical detection of anions

Bis-calix[4]arenes bridged by an electroactive tetrathiafulvalene unit.

Hybrid perovskite resulting from the solid-state reaction between the organic cations and perovskite layers of alpha1-(Br-(CH(2))(2)-NH(3))(2)PbI(4).