Rational integration of selective growth of CsCu 2 I 3 with rod-shaped and graphitic carbon nitride (g-C 3 N 4 ) nanoparticles was implemented by anti-solvent-assisted crystallization method and calcination. Therefore, a novel nitrogen vacances (V N ) defects enriched g-C 3 N 4 /CsCu 2 I 3 (CN/CCI) nanoheterostructure was expected prepared. The study revealed that the synergistic effect between the type-II and S-scheme charge transfer (CT) mechanisms and the strong adsorption capacity afforded by abundant surface V N defects significantly enhances the catalytic reaction efficiency. This synergy endows the CN/CCI heterojunction with superior performance compared to individual semiconductors. The interfacial charge transfer mechanisms (type-II and S-scheme) and the ultrafast dynamic processes in CN/CCI nano-heterojunctions were proposed and evaluated using nanosecond time-resolved transient photoluminescence spectroscopy and in-situ X-ray photoelectron spectroscopy. Following this scheme, the distinctive configuration of CN/CCI-6 heterojunctions demonstrated remarkable sensitivity reaching 5.66 in response towards 40 ppm of NO 2 operating at room temperature under ultraviolet-visible light activation, which is nearly 8.3 and 5.8 times greater than the sensitivity observed with pristine CsCu 2 I 3 and pure g-C 3 N 4 , respectively. Furthermore, the CN/CCI-6 nanoheterostructures also exhibited fastest response/recovery time (27.3 s/37.8 s) characteristics than that of pristine CsCu 2 I 3 (34.3 s/47.5 s) and pure g-C 3 N 4 (33.6 s/45.9 s). Additionally, we propose that the temperature - dependent photoluminescence of CN/CCI-6 could be exploited for the evaluation of the thermal-sensing with max sensitivity of 0.0093 K −1 at 550 K, indicating the CN/CCI nanoheterostructure is well suited for wide-range temperature sensing. The synergistic effect arising from the formation of V N defects and the efficient S-scheme CT manner within the CN/CCI nanoheterojunction holds significant implications and serves as an important reference for the development of high-performance gas & thermal-sensing.

Reliable phantoms for validating diffusion tensor imaging (DTI) and T 2 /T 2 ∗ mapping are crucial for standardizing neuroimaging, especially in the context of iron-related neurodegeneration. Here, a novel dual-functional MRI phantom is developed using coaxial electrospinning to embed Fe 3 O 4 nanoparticles within polycaprolactone (PCL) microfibres. The resulting hollow, axon-mimicking fibres exhibit tunable magnetic and mechanical properties that simulate iron deposition in neural tissue. The phantom's architecture and Fe 3 O 4 concentration modulate fractional anisotropy, mean diffusivity, and relaxation times, effectively recapitulating MRI signatures observed in diseases like Alzheimer's and Parkinson's. Comprehensive physicochemical characterization confirms structural fidelity, thermal behaviour, and anisotropic mechanical response. Crucially, the phantom enables simultaneous DTI and T 2 /T 2 ∗ imaging under clinical MRI protocols, offering a standardized, reproducible platform for imaging validation and harmonization. This multifunctional approach bridges a critical gap in quantitative neuroimaging and presents a new class of intelligent biomaterials for MRI system calibration and pathology modelling. A multifunctional MRI phantom is developed using co-electrospun hollow fibres embedded with Fe 3 O 4 nanoparticles to simulate iron accumulation in brain tissue. The phantom supports dual-modal T 2 and T 2 ∗ MRI contrast, enabling precise validation of neuroimaging techniques. This platform bridges materials engineering and medical imaging, offering new tools for diagnosing and monitoring neurodegenerative diseases.