Soft Ferroelectrics Enabling High‐Performance Intelligent Photo Electronics

Abstract

There has been a significant success in the synthesis of materials based on novel ferroelectric switching principles [10,11] and crystal engineering [12] (maximizing the ferroelectric properties for interface engineering to optimize contacts in devices). One evidence is that soft ferroelectrics have become crucial, particularly with the recent advancements in humanconnected electronics owing to extensive research success in human-machine interactive information, human safety, and human sustainability. [13] For instance, soft ferroelectrics with nonvolatile information storage capacity have been used in neuromorphic synaptic devices that can mimic the human neuronal system. [14][15][16][17][18][19][20][21] Relying on the piezoelectric properties possess by all soft ferroelectrics, a variety of tactile sensing memories that can simultaneously detect and store various tactile stimuli, such as pressure and friction, have been developed. [22,23] Specifically, soft ferroelectric domains embedded in semiconducting mediums are electrically programmable in remnant polarization, and the resulting programmed electric field successfully modulates the carrier transport of the semiconducting layer, leading to the development of not only high-performance photoelectronic devices but also those with new functionalities. [24,25] To design soft ferroelectrics materials for human-connected electronics properly, a comprehensive understanding of ferroelectric molecular switching mechanisms is necessary. It is also critical for understanding the intrinsic properties (such as working temperature, power consumption, amount of internal field related to Curie temperature, coercive field, and remnant polarization) of soft ferroelectrics that are technologically appropriate for device operation. This will make them suitable for developing human-connected electronics. Thus, proper screening of soft ferroelectrics by targeting complementary electronic devices is also necessary. Efforts should be made to control the crystallization during the preparation of thin, uniform, and pinhole-free soft ferroelectric films by controlling the solute-solvent chemistry of composition. The recent development of these micro-and nanostructured approaches suggests that multiscale, multidimension, and periodic microor nanopatterned soft ferroelectrics will not only significantly enhance the efficiency of various photoelectronic devices, but it will also result in new novel functionalities (such as anisotropic and directional photoelectronic properties) and thus Soft ferroelectrics based on organic and organic-inorganic hybrid materials have gained much interest among researchers owing to their electrically programmable and remnant polarization. This allows for the development of numerous flexible, foldable, and stretchable nonvolatile memories, when combined with various crystal engineering approaches to optimize their performance. Soft ferroelectrics have been recently considered to have an important role in the emerging human-connected electronics that involve...

Glycine: The Gift that Keeps on Giving

“…The fact that they posess these properties served as additional proof that the crystal structures are not centrosymmetric, which was important at the times when the develop-ment of the diffraction technique did not allow for confidence in the coordinates of H-atoms in the structure. Since that time interest in the physical properties of the crystalline amino acids has grown enormously, in view of their potential applications as functional materials, [236][237][238][239][240][241][242][243][244][245][246] to understand the biophysical processes [86,247,248] and to create new biomedical materials. [86,246,[249][250][251][252][253][254][255] While the piezoelectric properties of individual single crystals of γ-glycine are fascinating, so too are the physical properties of its assemblies (powder samples).…”

Enhanced Photoresponse in GeSe‐Based Phototransistors by Ferroelectric Gating

“…A recent research also shows that the response time of several photodetectors, such as the one based on NiO, is only marginally influenced by the ferroelectric field. [26,38] To better understand the physical mechanism of the enhanced photoresponsivity under ferroelectric gating, the energy band diagrams of the GeSe-based phototransistors under different working states are schematically shown in Figure 7. As shown in Figure 7a, under zero source-drain bias or gate voltage in the dark state, the Fermi level (E F ) of GeSe is close to the valence band edge (E V ) due to the natural p-doping.…”

Organic Synaptic Transistors: The Evolutionary Path from Memory Cells to the Application of Artificial Neural Networks

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