One-dimensional (1D) metal oxide nanomaterials attract increasing interest for supercapacitor applications. Therefore, the rational design and facile construction of unique 1D heterostructures remain highly desirable for advanced energy storage. Herein, a novel architecture comprising 1D SnO2 nanofibers (NFs) uniformly decorated with 0D WO3 nanoparticles (NPs) is successfully fabricated via coaxial electrospinning coupled with subsequent thermal calcination. By finely tuning the molar ratio of the respective precursors, the loading density of the WO3 NPs on the SnO2 skeleton is precisely modulated. This distinctive 1D/0D heterostructure effectively exposes abundant electroactive sites and significantly augments the interfacial contact area with the electrolyte, synergistically boosting the electrochemical kinetics. Consequently, at an optimal WO3-to-SnO2 molar ratio of 1:1, the assembled SWHNC-2 electrode delivers a specific capacitance of 238.3 F g−1 at 1 A g−1. It also exhibits suitable rate capability (retaining 56.7% capacitance at 10 A g−1) and moderate cycling stability (91.2% capacitance retention over 2000 cycles at 5 A g−1). Moreover, a symmetric supercapacitor assembled from this composite achieves maximum energy density of 4.64 Wh kg−1 at a power density of 448 W kg−1, while maintaining 78% of its initial capacitance after 1000 cycles, indicating its preliminary potential for energy storage. These findings unequivocally highlight the rationally engineered SnO2@WO3 composite as a promising electrode candidate for next-generation supercapacitors.
Self-activated oxide based double perovskite phosphors offer distinct advantages over conventional phosphors by avoiding quenching issues while providing enhanced thermal and chemical stability and greater structural versatility. In the present study, a series of Er3+/Yb3+: La2ZnMnO6 (LZMO) phosphors exhibiting ultra-broadband upconversion (UC) have been successfully synthesized and systematically characterized through XRD, FTIR, HR-TEM, FESEM, XPS, and DRS to investigate their structural, morphological, and optical properties. Under 980 nm excitation, the undoped phosphor has exhibited an ultra-broadband UC emission covering the 400-900 nm region, comprising two prominent broad bands centred at ∼ 635 nm (400-687 nm) and ∼710 nm (687-900 nm), attributed to the electronic transitions of Mn ions in the host lattice. Notably, the introduction of Er3+ doping and Er3+/Yb3+ co-doping has significantly enhanced the integrated broadband UC intensity by ∼ 10-fold and 30-fold, respectively. Furthermore, laser power dependent studies confirm the two-photon UC process, reinforced by the proposed energy level diagram, provide valuable insight into the broadband emission mechanism in the Er3+/Yb3+: LZMO system. The thermometric performance has been evaluated over the 303-523 K range using the fluorescence intensity ratio (FIR) technique based on the non-thermally coupled emission ratio (I635/I710), achieving a maximum absolute and relative sensitivities of ∼1.18 × 10-3 K-1 and ∼ 0.046% K-1 at 303 K, respectively. Moreover, the phosphors have shown an ∼1.52-fold enhancement in the integrated UC emission intensity at 523 K relative to 303 K, indicating negative thermal quenching behaviour. Additionally, the phosphor has been rationally designed to perform AND, INHIBIT, and DEMUX molecular logic operations by employing temperature modulation and NIR excitation as dual input stimuli, with sensing parameters serving as the output.
The RAlO3 orthoaluminates have garnered significant attention owing to their giant magnetic entropy change (−ΔSM) at cryogenic temperature. In this paper, we have prepared high quality GdAlO3 single crystals and studied the anisotropic magnetic property and magnetocaloric (MC) effect. With decreasing temperature, the antiferromagnetic (AFM) interaction occurs between the nearest-neighbor Gd3+ ions at the Néel temperature (TN) of 3.96 K. The magnetization measured along the three crystallographic axes shows observable differences, revealing the magnetic anisotropy of this system. Through comparative analysis of the magnetization data, the a axis has been identified as the direction of the AFM sublattice arrangement. The responses of Gd sublattices to the magnetic field yield a −ΔSM of 28.12 J kg−1K−1 along the a axis under the field change of 5 T near TN, suggesting a giant MC effect. A large rotating entropy change about 7.32 J kg−1K−1 is obtained between a and c axes. Moreover, considerable temperature-averaged entropy change covers a relatively wide temperature range, indicating that GdAlO3 single crystal is a thermal efficient material with wide operating temperature range.
Bone-mimetic scaffolds are anticipated to efficiently regenerate bone defects. Calcium magnesium phosphate (Ca3Mg3(PO4)4; CMP) and triply periodic minimal surface (TPMS) resemble the composition and structural architecture of natural bone, respectively. In this study, CMP bioceramic scaffolds with Diamond-type TPMS architecture were fabricated via ceramic stereolithography (CSLA). Scaffolds with varying unit cell lengths (CL: 0.9, 1.05, and 1.2 mm) were prepared alongside a grid-like (Grid) scaffolds as the control. The CSLA-fabricated bioceramic scaffolds exhibited high structural fidelity to the designed architecture. The Diamond-type bioceramic scaffolds exhibited superior compressive strength compared to the Grid scaffolds, with the CL0.9 scaffolds achieving the maximum value. The Diamond-type scaffolds, particularly the CL0.9 scaffolds, exhibited enhanced osteogenic activity compared with the Grid scaffolds. Overall, the topologically tunable Diamond-type CMP bioceramic scaffolds achieved a favorable balance between physicochemical characteristics and cellular responses, highlighting their suitability for bone repair.
Lead-free BNT-BT piezoelectric ceramics present excellent piezoelectric properties and are non-toxic, positioning them as one of the most promising lead-free ceramic systems for industrial applications. However, the typically issue is a low depolarization temperature (Td). Moreover, an increase in Td is accompanied by a reduction in the piezoelectric coefficient (d33), which severely hinders the improvement of piezoelectric performance and restricts applications at high temperatures. Accordingly, (Zn0.2Zr0.2Fe0.2Mo0.2Sb0.2)O2 is doped into 0.935Bi0.5Na0.5TiO3-0.065BaTiO3 with the morphotropic phase boundary (MPB) through the high-entropy doping strategy in this study, to design the system of 0.935Bi0.5Na0.5(Zn0.2Zr0.2Fe0.2Mo0.2Sb0.2)xTi(1-x)O3-0.065BaTiO3. High-entropy doping at the B-site induces lattice distortion and increases defect density, thereby generating domain-wall pinning and ultimately enabling the synergistic enhancement of Td and d33. Notably, at x = 0.1%, d33 reaches 200 pC/N and Td increases to 108 °C, achieving simultaneous optimization of piezoelectric performance and temperature stability. These results indicate that high-entropy doping effectively addresses the issue of simultaneous optimization encountered in conventional doping, thereby providing a novel strategy to achieve synergistic optimization of Td and d33.
