Journal of Materials Chemistry C最新文献

We report a new class of photo-responsive polar nanostructured liquid crystals. Controlled aromatic core fluorination directs self-assembly into a novel tetragonal mesophase with co-existing columns and micelles. These unique nanostructured materials enable tunable charge transport, providing a design model for functional organic semiconductors.

Vanadium oxide (VO_x)-based bolometric membrane films with high temperature coefficient of resistance (TCR) and low 1/f noise were deposited by tuning the argon and oxygen flow rate inside a DC magnetron sputtering chamber. The process temperature was maintained below 300 °C so that the film was compatible with the readout integrated circuit (ROIC). Initially, the phase fraction was optimized at the elevated temperature of 550 °C, and later, the optimized argon and oxygen flow rate ratio was used to deposit the film at its deposition temperature, i.e., 250 °C. The TCR value of −3.4% K⁻¹ and sheet resistivity of 1.2 ohm sq⁻¹ were obtained for an optimized argon and oxygen flow rate ratio at 550 °C, while TCR > −2.2% K⁻¹ was obtained for films deposited at 250 °C. Additionally, a 1/f noise constant with the order of K = 10⁻¹² was obtained for the films. Qualitative and quantitative analyses of films were carried out using X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, and atomic force microscopy. Finally, first-principles density functional theory (DFT) calculations were performed to analyse the influence of phases on the TCR of the films grown using the optimized parameters.

The efficiency of quantum-dot light-emitting diodes (QLEDs) has improved, with the efficiency of red, green, and blue QLED devices exceeding 20%. However, poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) materials commonly used in QLEDs suffer from several drawbacks, such as hygroscopicity and a tendency to corrode ITO electrodes, which negatively affect the device operation time and commercial viability. As p-type oxide semiconductors, NiO_x exhibits high optical transparency, a tunable work function and an adjustable electronic structure, which enable it to be suitable for use as a hole injection layer (HIL) with electron-blocking properties. Furthermore, low-cost fabrication is required to form a charge transport layer at low temperatures by a solution process. In this review, different solution methods for preparing NiO_x and the recent advances in the development of NiO_x based QLEDs are both summarized. More stable QLEDs are obtained through NiO_x modification, doping, post-treatment, device structural optimization, and so on. The potential future research directions are outlined to guide further advancements in QLED technology and further studies to fully understand it at a deeper level are highly needed.

A unipolar organic semiconductor with high mobility is crucial for various optoelectronic devices. In this study, a benzo[c]cinnoline-based organic semiconductor (TPA)₂Ab with ambipolar transport properties is converted into a unipolar (p-type) semiconductor by reacting with the Lewis acid palladium tetrachloride (PtCl₄). This reaction reduces the hole trap-state density of (TPA)₂Ab from approximately 10¹⁶ cm⁻³ to a level where a measurable trap-filled limit (V_TFL) cannot be detected in the resulting [(TPA)₂Ab]PtCl₄ complex. Consequently, the hole mobility increases significantly from 3.4 × 10⁻⁵ to 3.9 × 10⁻³ cm² V⁻¹ s⁻¹, followed by a reduction in electron mobility from 1.4 × 10⁻⁵ to 4.1 × 10⁻⁷ cm² V⁻¹ s⁻¹.

Lead zirconate titanate (PZT) piezoelectric films are widely used in electronic devices due to their excellent piezoelectric properties. However, their poor adaptability to rigid substrates and material brittleness restrict their development in flexible electronics. This paper systematically reviews the key preparation technologies and performance optimization strategies of flexible PZT films: material composites (such as PZT/polyvinylidene fluoride (PVDF), PZT/polydimethylsiloxane (PDMS)), direct growth on flexible substrates (mica, stainless steel foil), substrate transfer (laser lift-off, chemical etching), and process optimization (low-temperature crystallization, gradient layer design) significantly enhance film flexibility, with elongation at break increased by more than 3 times and bending cycle life exceeding 10⁴ times. Meanwhile, piezoelectric coefficients (d₃₃) are improved through morphotropic phase boundary (MPB) regulation, element doping (La³⁺, Sm³⁺), and microstructural optimization. Flexible PZT films show important application values in wearable sensors, energy harvesting, bionic electronics, etc., such as human motion monitoring, self-powered nanogenerators, and bionic electronic skin. Future research should focus on the compatibility of high-temperature processes with flexible substrates, synergistic optimization of piezoelectricity and flexibility, and integrated device design.

Optoelectronic inhibitory synapses play critical roles in modulating neural activity and maintaining the balance between excitation and inhibition within artificial neural circuits. However, most reported devices fail to properly emulate depression-related synaptic functions under optical stimulation. In this work, we demonstrate an optoelectronic inhibitory synaptic device based on lead sulfide (PbS) nanocrystals capped with iodide ligands. Crucially, the devices operate in the visible range (RGB), essential for retina-inspired color sensing, demonstrating inhibitory postsynaptic current (IPSC) behavior under 450, 550 and 740 nm illumination. A low power consumption of ∼40 nJ was also recorded under red light illumination. The system successfully emulates fundamental synaptic behaviors including paired-pulse depression (PPD), spiking-number-dependent plasticity (SNDP), and spiking-rate-dependent plasticity (SRDP), enabling biologically plausible visual processing.

Correction for ‘Multifunctional benzonitrile derivatives with TADF and mechanofluorochromic properties and their application in OLEDs’ by Antonio Maggiore et al., J. Mater. Chem. C, 2025, 13, 13752–13767, https://doi.org/10.1039/D4TC04347B.

While the clusteroluminescence (CTE) of cucurbiturils has been established, a systematic understanding of how their macrocyclic structure dictates the emission efficiency remains elusive. Herein, we explore how polymerization degree and substituents affect the clusteroluminescence (CTE) of cucurbiturils. All tested Q[5–8] and methyl-substituted Q[6] crystals exhibited excitation-dependent fluorescence and phosphorescence. Q[6] and Q[7] exhibited superior multicolor emission, while methyl substitution weakened this property. Structural and theoretical analyses revealed CTE's dependence on self-assembled unit number and packing density.

Reservoir computing (RC) provides a training-efficient alternative to recurrent neural networks by fixing recurrent weights and training only a linear readout. In hardware, physical reservoirs harness intrinsic device dynamics to supply the three requisites for temporal computation: nonlinearity, short-term memory, and resulting high-dimensional state richness. This review summarises RC fundamentals and maps device requirements onto materials properties including domain nucleation, hysteresis, depolarisation-driven volatility, and multiscale relaxation. We survey representative ferroelectric platforms, including hafnia-based ferroelectric field-effect transistors (FeFETs), ferroelectric tunnel junctions (FTJs), and ferroelectric thin-film transistors (FeTFTs), together with their antiferroelectric variants. These devices inherently support nonlinear input–state mapping, tunable fading memory, and rich intermediate states. Implementation strategies include multiplexing and single-device reservoirs, evaluated against metrics for memory capacity and energy–latency–accuracy. Emphasis is placed on complementary-metal-oxide–semiconductor compatible HfO₂ for scalability, fast switching, and low-voltage operation. Reliability and variability are reframed as resources through interface and defect engineering. Ferroelectrics emerge as energy-efficient reservoirs for robust temporal inference at the edge.

Microwave dielectric ceramics with low permittivity (ε_r < 15) have become a critical research focus in the millimeter-wave communication era due to their ultra-low dielectric loss and high-frequency stability, especially as the rapid global proliferation of 5G and 6G communication technologies continues. In this study, the phase evolution of CaCuGe₂O₆ ceramics was systematically investigated using X-ray diffraction (XRD) combined with Rietveld refinement. The results revealed that, with increasing sintering temperature, secondary phases in the material gradually decomposed, ultimately enabling the successful preparation of single-phase CaCuGe₂O₆ ceramics (space group: P2₁/c) under optimal sintering conditions. Scanning electron microscopy (SEM) characterization showed that samples sintered at 1020 °C exhibited optimal surface morphology, achieving superior microwave dielectric properties (ε_r = 8.86, Q × f = 21 301 GHz, τ_f = −90.26 ppm °C⁻¹) and high densification. A thorough investigation of the factors governing performance established correlations between density and both ε_r and Q × f values, as well as the evolution of temperature stability with sintering temperature. It has been demonstrated that CaCuGe₂O₆ ceramics have significant potential as novel materials for core components such as base-station filters and antenna substrates, offering new insights into the design of high-frequency communication devices.