ABSTRACT The rapid expansion of the Internet of Things and wearable electronics demands gas sensors that combine high sensitivity with ultralow power consumption. Traditional metal oxide semiconductor sensors require elevated temperatures (100–400°C) and consume substantial power, creating fundamental barriers for battery‐powered and on‐body applications. Room‐temperature operation addresses these power constraints but introduces challenges from sluggish surface kinetics and weak signal transduction. Surface functionalization strategies such as catalytic decoration and defect engineering can enhance interfacial reactivity and improve molecular selectivity. Heterojunction architectures and field‐effect transistor configurations provide signal amplification through barrier‐controlled charge transport and transconductance gain. Low‐energy activation techniques including photoactivation, pulsed heating, and temperature modulation offer pathways to accelerate surface reactions without continuous thermal input. Artificial intelligence algorithms enable the extraction of complex temporal and spectral features for pattern recognition and drift compensation in dynamic environments. However, translating laboratory prototypes into field‐ready devices requires addressing humidity interference, long‐term baseline stability, and system‐level integration under strict energy budgets. Unlike prior reviews that address these domains in isolation, this review integrates RT sensing mechanisms, low‐energy activation, real‐world deployment strategies, and AI‐enabled signal processing into a unified framework for energy‐constrained IoT and wearable applications.
ABSTRACT Short‐wave infrared (SWIR) organic light‐emitting diodes (OLEDs) have received intense attention, owing to rapid progress in their applications in biomedicine and optoelectronics, although their electroluminescence (EL) efficiency is still far from unity. Recently, various fluorescent acceptor–donor–acceptor (A–D–A) type aromatic fused‐ring non‐fullerene acceptors have demonstrated effective suppression of non‐radiative losses in organic photovoltaics, rendering them promising candidates for SWIR OLEDs. Nevertheless, SWIR fluorescent emitters remain scarce in terms of molecular structure diversity, and state‐of‐the‐art SWIR OLEDs are still limited by relatively low radiative efficiency, unbalanced injection and transport of charge carriers, and light out‐coupling efficiency. In this study, we report high‐performance SWIR OLEDs from a novel A–D–A molecule, named DNIC, in which the traditional carbazole moiety is replaced with an indolo[3,2‐b]indole moiety as a strong electron‐donating group. Owing to enhanced intramolecular charge transfer arising from the multiple donor‐acceptor (D–A) effect within the conjugated backbone, DNIC possesses a narrow optical bandgap of 1.22 eV. By doping DNIC into a near infrared (NIR) emitter Y11, we achieve a maximum external quantum efficiency (EQE) of 0.023% for EL with an emission peak at 1071 nm, outperforming the neat film‐based devices (0.010%) and thus placing it among the best SWIR OLEDs reported to date.
ABSTRACT Extrusion bioprinting is a promising tool for autonomous medical care and biomanufacturing during long‐duration crewed space missions. However, the implementation of this technology depends on how cell‐laden bioinks can be brought to the space platform without compromising their biological functionality. In this study, a supply chain solution is introduced in which cells and acellular biomaterial ink are transported separately (cells as cryopreserved vials at −80°C and the ink at 4°C) and are combined into the final bioink minutes before printing. This cryo‐based bioink approach is validated against a freshly prepared reference bioink and a premixed, cold‐stored bioink using a parabolic flight campaign, including the logistic chain of road transport to the flight site, crew‐level preparation in Bordeaux, in‐flight printing during microgravity, and post‐flight sample return to Dresden for cultivation. Human dermal fibroblasts printed with the cryo‐based bioink reach viabilities above 90%, comparable to the reference group. In contrast, the viability of the cells printed from cold‐stored bioink declined and with no detectable cells at the final cultivation time point. Our results show that decoupling cells and biomaterial ink through cryopreservation preserves biological functionality and enables a scalable bioink supply chain using infrastructure available on crewed space platforms.
