In situ training of an in-sensor artificial neural network based on ferroelectric photosensors.

In-sensor computing has emerged as an ultrafast and low-power technique for next-generation machine vision. However, in situ training of in-sensor computing systems remains challenging due to the demands for both high-performance devices and efficient programming schemes. Here, we experimentally demonstrate the in situ training of an in-sensor artificial neural network (ANN) based on ferroelectric photosensors (FE-PSs).

Regulation of the Buried Interface to Achieve Efficient HTL-Free All-Inorganic CsPbIBr-Based Perovskite Solar Cells.

The large voltage loss () mainly stems from the mismatch between the perovskite film and electron transport layer in CsPbIBr-based all-inorganic perovskite solar cells (I-PSCs), which restricts the power conversion efficiency (PCE) of devices. To address this issue, potassium benzoate (BAP) is first introduced as a bifunctional passivation material to regulate the TiO/CsPbIBr interface, reduce the , and improve the photovoltaic performance of CsPbIBr-based I-PSCs. Eventually, the champion PCE of CsPbIBr-based I-PSCs without a hole transport layer modified by BAP (Target-PSCs) improves to 14.

Multifunctional Acetaminophen Interlayer for High Efficiency and Durability Lead-Lean Perovskite Solar Cells.

Due to the easy oxidation of Sn, which leads to form tin vacancy defects and poor perovskite film quality, caused by the rapid crystallization rate in tin-based perovskite solar cells (PSCs), their efficiency lags far behind that of lead-based PSCs. To improve the photovoltaic (PV) performance and stability of FAPEASnI-based PSCs (T-PSCs), a small amount of Pb(SCN) is introduced into a perovskite precursor as an antioxidant, and acetaminophen (ACE) with various functional groups is used to modify a poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS)/perovskite interface. The results show that the Pb(SCN) additive and ACE interfacial modification can not only optimize energy level alignment in T-PSCs but also inhibit Sn oxidation to reduce the trap-state density, resulting in promoted carrier transport.

Organic-Inorganic Hybrid Perovskite Ferroelectric Nanosheets Synthesized by a Room-Temperature Antisolvent Method.

Over the past years, the application potential of ferroelectric nanomaterials with unique physical properties for modern electronics is highlighted to a large extent. However, it is relatively challenging to fabricate inorganic ferroelectric nanomaterials, which is a process depending on a vacuum atmosphere at high temperatures. As significant complements to inorganic ferroelectric nanomaterials, the nanomaterials of molecular ferroelectrics are rarely reported.

Room-temperature sub-100 nm Néel-type skyrmions in non-stoichiometric van der Waals ferromagnet FeGaTe with ultrafast laser writability.

Realizing room-temperature magnetic skyrmions in two-dimensional van der Waals ferromagnets offers unparalleled prospects for future spintronic applications. However, due to the intrinsic spin fluctuations that suppress atomic long-range magnetic order and the inherent inversion crystal symmetry that excludes the presence of the Dzyaloshinskii-Moriya interaction, achieving room-temperature skyrmions in 2D magnets remains a formidable challenge. In this study, we target room-temperature 2D magnet FeGaTe and unveil that the introduction of iron-deficient into this compound enables spatial inversion symmetry breaking, thus inducing a significant Dzyaloshinskii-Moriya interaction that brings about room-temperature Néel-type skyrmions with unprecedentedly small size.

Strain-Induced Reversible Motion of Skyrmions at Room Temperature.

Magnetic skyrmions are topologically protected swirling spin textures with great potential for future spintronic applications. The ability to induce skyrmion motion using mechanical strain not only stimulates the exploration of exotic physics but also affords the opportunity to develop energy-efficient spintronic devices. However, the experimental realization of strain-driven skyrmion motion remains a formidable challenge.

In-plane charged antiphase boundary and 180° domain wall in a ferroelectric film.

The deterministic creation and modification of domain walls in ferroelectric films have attracted broad interest due to their unprecedented potential as the active element in non-volatile memory, logic computation and energy-harvesting technologies. However, the correlation between charged and antiphase states, and their hybridization into a single domain wall still remain elusive. Here we demonstrate the facile fabrication of antiphase boundaries in BiFeO thin films using a He-ion implantation process.

Defective ReS Triggers High Intrinsic Piezoelectricity for Piezo-Photocatalytic Efficient Sterilization.

Rhenium disulfide (ReS) is a promising piezoelectric catalyst due to its excellent electron transfer ability and abundant unsaturated sites. The 1T' phase structure leads to the evolution of ReS into a centrosymmetric spatial structure, which restricts its application in piezoelectric catalysis. Herein, we propose a controllable defect engineering strategy to trigger the piezoelectric response of ReS.

Controllable Skyrmionic Phase Transition between Néel Skyrmions and Bloch Skyrmionic Bubbles in van der Waals Ferromagnet Fe GeTe.

The van der Waals (vdW) ferromagnet Fe GeTe has garnered significant research interest as a platform for skyrmionic spin configurations, that is, skyrmions and skyrmionic bubbles. However, despite extensive efforts, the origin of the Dzyaloshinskii-Moriya interaction (DMI) in Fe GeTe remains elusive, making it challenging to acquire these skyrmionic phases in a controlled manner. In this study, it is demonstrated that the Fe content in Fe GeTe has a profound effect on the crystal structure, DMI, and skyrmionic phase.

Significantly Improved Efficiency and Stability of Pure Tin-Based Perovskite Solar Cells with Bifunctional Molecules.

Tin-based perovskite solar cells (TPSCs) have become one of the most prospective photovoltaic materials due to their remarkable optoelectronic properties and relatively low toxicity. Nevertheless, the rapid crystallization of perovskites and the easy oxidization of Sn to Sn make it challenging to fabricate efficient TPSCs. In this work, a piperazine iodide (PI) material with -NH- and -NH- bifunctional groups is synthesized and introduced into the PEAFASnI-based precursor solution to tune the microstructure, charge transport, and stability of TPSCs.

All-ferroelectric implementation of reservoir computing.

Reservoir computing (RC) offers efficient temporal information processing with low training cost. All-ferroelectric implementation of RC is appealing because it can fully exploit the merits of ferroelectric memristors (e.g.

Constructing Type-II and S-Scheme Heterojunctions of CuO@Cu(SO)(OH)·HO Polyhedra by In Situ Etching CuO with Different Exposed Facets for Enhanced Photocatalytic Sterilization and Degradation Performance.

The construction of type-II or S-scheme heterojunctions can effectively accelerate the directional migration of charge carriers and inhibit the recombination of electron-hole pairs to improve the catalytic performance of the composite catalyst; therefore, the construction and formation mechanism of a heterojunction are worth further investigation. Herein, CuO@Cu(SO)(OH)·HO core-shell polyhedral heterojunctions were fabricated via in situ etching CuO with octahedral, cuboctahedral, and cubic shapes by sodium thiosulfate (NaSO). CuO@Cu(SO)(OH)·HO polyhedral heterojunctions demonstrated obviously enhanced sterilization and degradation performance than the corresponding single CuO polyhedra and Cu(SO)(OH)·HO.

Strain Tuning of Negative Capacitance in Ferroelectric KNbO Thin Films.

Ferroelectrics with negative capacitance effects can amplify the gate voltage in field-effect transistors to achieve low power operation beyond the limits of Boltzmann's Tyranny. The reduction of power consumption depends on the capacitance matching between the ferroelectric layer and gate dielectrics, which can be well controlled by adjusting the negative capacitance effect in ferroelectrics. However, it is a great challenge to experimentally tune the negative capacitance effect.

Local Manipulation of Skyrmion Nucleation in Microscale Areas of a Thin Film with Nitrogen-Ion Implantation.

Precise manipulation of skyrmion nucleation in microscale or nanoscale areas of thin films is a critical issue in developing high-efficient skyrmionic memories and logic devices. Presently, the mainstream controlling strategies focus on the application of external stimuli to tailor the intrinsic attributes of charge, spin, and lattice. This work reports effective skyrmion manipulation by controllably modifying the lattice defect through ion implantation, which is potentially compatible with large-scale integrated circuit technology.

Band Position-Independent Piezo-Electrocatalysis for Ultrahigh CO Conversion.

Piezo-electrocatalysis as an emerging mechano-to-chemistry energy conversion technique opens multiple innovative opportunities and draws great interest over the past decade. However, the two potential mechanisms in piezo-electrocatalysis, i.e.

Current-Induced Reversible Split of Elliptically Distorted Skyrmions in Geometrically Confined Fe Sn Nanotrack.

Skyrmions are swirling spin textures with topological characters promising for future spintronic applications. Skyrmionic devices typically rely on the electrical manipulation of skyrmions with a circular shape. However, manipulating elliptically distorted skyrmions can lead to numerous exotic magneto-electrical functions distinct from those of conventional circular skyrmions, significantly broadening the capability to design innovative spintronic devices.

Performance estimation for the memristor-based computing-in-memory implementation of extremely factorized network for real-time and low-power semantic segmentation.

Nowadays many semantic segmentation algorithms have achieved satisfactory accuracy on von Neumann platforms (e.g., GPU), but the speed and energy consumption have not meet the high requirements of certain edge applications like autonomous driving.

Cinnamate-Functionalized Cellulose Nanocrystals as Interfacial Layers for Efficient and Stable Perovskite Solar Cells.

The poor interfacial contact and imperfections between the charge transport layer and perovskite film often result in carrier recombination, inefficient charge collection, and inferior stability of perovskite solar cells (PSCs). Therefore, interface engineering is quite crucial to achieve high-performance and stable PSCs. Here, we introduced a cinnamate-functionalized cellulose nanocrystals (Cin-CNCs) interfacial layer between SnO and perovskite active layer for enhancing carrier transport ability and crystal growth of perovskite, meanwhile endowing additional functional of long-term device stability against ultraviolet light.

Ultrahigh Polarization Response along Large Energy Storage Properties in BiFeO-BaTiO-Based Relaxor Ferroelectric Ceramics under Low Electric Field.

BiFeO-BaTiO (BF-BT) dielectric ceramics are receiving more and more concern for advanced energy storage devices owing to their excellent ferroelectric properties and environmental sustainability. However, the energy density and efficiency are limited in spite of the large remanent polarization. Herein, we proposed a multiscale optimization strategy via a local compositional disorder with a Birich content and nanodomain engineering by introducing the SrBiCaTiO (SBCT) into BF-BT ceramics.

Constructing molecular bridge for high-efficiency and stable perovskite solar cells based on P3HT.

Poly (3-hexylthiophene) (P3HT) is one of the most attractive hole transport materials (HTMs) for the pursuit of stable, low-cost, and high-efficiency perovskite solar cells (PSCs). However, the poor contact and the severe recombination at P3HT/perovskite interface lead to a low power conversion efficiency (PCE). Thus, we construct a molecular bridge, 2-((7-(4-(bis(4-methoxyphenyl)amino)phenyl)-10-(2-(2-ethoxyethoxy)ethyl)-10H-phenoxazin-3-yl)methylene)malononitrile (MDN), whose malononitrile group can anchor the perovskite surface while the triphenylamine group can form π-π stacking with P3HT, to form a charge transport channel.

A Nontoxic NFM Solvent for High-Efficiency Perovskite Solar Cells with a Widened Processing Window.

With the steady industrialization process of the perovskite solar cells (PSCs), the toxicity of the used solvents has become a pivotal issue that needs to be addressed. Especially, the usage of ,-dimethylformamide (DMF) solvent would pose serious environmental and health concerns. Herein, we have reported a nontoxic solvent -formylmorpholine (NFM) to replace the toxic DMF and have achieved a higher PCE of 22.

Enhanced Ferroelectric and Piezoelectric Properties in Graphene-Electroded Pb(Zr,Ti)O Thin Films.

While using ferroelectric polarization to tune the functional properties of 2D materials has been extensively studied recently, the effects of 2D materials on the ferroelectricity and piezoelectricity of ferroelectrics are much less explored. In this work, we report markedly enhanced ferroelectric and piezoelectric properties of graphene/Pb(ZrTi)O/SrRuO (GR/PZT/SRO) capacitors. Compared with conventional metal-electroded ferroelectric capacitors, the GR/PZT/SRO capacitors exhibit more abrupt polarization switching, larger switchable polarization, lower leakage current, and smaller coercive voltage.