The development of ceramic capacitors featuring high reliability and superior comprehensive performance is vital for practical applications in medium electric fields. In this work, a synergistic strategy was proposed to improve the energy storage performance of (1 − x)0.94Bi_0.47Na_0.47Ba_0.06TiO₃-xCaTi_0.8Sn_0.2O₃ ((1 − x)BNBT-xCTS) ceramics by introducing polymorphic nanodomains and transforming rhombohedral (R3c) to tetragonal (P4bm) forms, exhibiting a superparaelectric state at room temperature (RT). Remarkably, a lead-free 0.75Bi_0.47Na_0.47Ba_0.06TiO₃-0.25CaTi_0.8Sn_0.2O₃ (0.75BNBT-0.25CTS) ceramic exhibits superior energy storage properties: W_rec = 5.81 J cm⁻³ and η = 90.5% at a moderate field of 315 kV cm⁻¹, along with promising frequency/temperature stability (1–200 Hz and 20–200 °C) as well as a fast discharge rate (t_0.9) of 72 ns. Additionally, the sample of 0.75Bi_0.47Na_0.47Ba_0.06TiO₃-0.25CaTi_0.8Sn_0.2O₃ shows excellent dielectric constant and thermal stability (Δε′/ε′_{25 °C} ≤ ±15% at 1 kHz) in the range of −120 to 204 °C, satisfying the XR9-type capacitor. This study shows that the construction of polymorphic nanodomains and superparaelectric states at RT is an effective strategy to obtain high-efficiency energy storage ceramics under medium electric fields.

Constructing 2D heterojunctions with high performance is the critical solution for the optoelectronic applications of 2D materials. This work reports on the studies on the preparation of high-quality van der Waals SiAs single crystals and high-performance photodetectors based on the 2D SiAs/SnS₂ heterojunction. The crystals are grown using the chemical vapor transport (CVT) method and then the bulk crystals are exfoliated to a few layers. Raman spectroscopic characterization shows that the low wavenumber peaks from interlayer vibrations shift significantly along with SiAs’ thickness. In addition, when van der Waals heterojunctions of p-type SiAs/n-type SnS₂ are fabricated, under the source-drain voltage of −1 V–1 V, they exhibit prominent rectification characteristics, and the ratio of forwarding conduction current to reverse shutdown current is close to 10², showing a muted response of 1 A/W under excitation light of 550 nm. The light responsivity and external quantum efficiency are increased by 100 times those of SiAs photodetectors. Our experimental results enrich the research on the IVA–VA group p-type layered semiconductors.

The structure directing effect of [SeO₃]²⁻ anionic groups play a crucial role in the configuration of ordered [MO₃F₃] octahedral and its large anisotropy.

New non-centrosymmetric antiperovskite (and double antiperovskite) borate-fluorides, [(M/Ba) ₂ Ca]F[B ₂ O ₅ ] (M = K, Rb) and [CsBaCa]F[B ₂ O ₅ ] have been designed and synthesized. They all exhibit the interesting nonlinear optical properties.