Multi-stimuli-responsive aggregation-induced emission copper iodide cluster

Stimuli-responsive luminescent materials have attracted significant attention in the development of smart photoactive materials for both fundamental research and technological applications.In this work,a new copper iodide cluster(1)with aggregationinduced emission(AIE)characteristic,was obtained combining Cu_(4)I_(4) core with rhodamine B derivative ligand.1 has reversible and distinct multi-stimuli-responsive luminescence for external temperature,volatile organic compound,and mechanical force.Significantly,1 exhibited unusual large blue shift(84 nm)after being ground,which originated from the change of intermolecular interactions.Moreover,1 exhibits high oxygen quenching efficiency for 82.2% at 1 bar.Mechanistic studies showed that the multi-stimuli-responsive luminescence properties of 1 can be attributed to the regulation of cluster-centered luminescence process,metal-to-ligand charge transfer process,halide-to-metal charge transfer luminescence process and aggregationinduced barrier to oxygen process.This work not only reports an AIE copper iodide cluster,but also provides a new strategy to develop multi-stimuli-responsive luminescence materials.

Direct 4D printing of functionally graded hydrogel networks for biodegradable,untethered,and multimorphic soft robots

Recent advances in functionally graded additive manufacturing(FGAM)technology have enabled the seamless hybridization of multiple functionalities in a single structure.Soft robotics can become one of the largest beneficiaries of these advances,through the design of a facile four-dimensional(4D)FGAM process that can grant an intelligent stimuli-responsive mechanical functionality to the printed objects.Herein,we present a simple binder jetting approach for the 4D printing of functionally graded porous multi-materials(FGMM)by introducing rationally designed graded multiphase feeder beds.Compositionally graded cross-linking agents gradually form stable porous network structures within aqueous polymer particles,enabling programmable hygroscopic deformation without complex mechanical designs.Furthermore,a systematic bed design incorporating additional functional agents enables a multi-stimuli-responsive and untethered soft robot with stark stimulus selectivity.The biodegradability of the proposed 4D-printed soft robot further ensures the sustainability of our approach,with immediate degradation rates of 96.6%within 72 h.The proposed 4D printing concept for FGMMs can create new opportunities for intelligent and sustainable additive manufacturing in soft robotics.

Photoactivated Circularly Polarized Room-Temperature Phosphorescence from Phenoselenazine Derivative and Its Application in Information Security

Room-temperature phosphorescence(RTP)materials have experienced rapid development due to their potential in organic light-emitting diode,information security,bioimaging,etc.However,the design of chiral organic phosphors with circularly polarized RTP(CPP)property remains a formidable challenge.Here,we introduce a chiral perturbation approach using a combination of chiral binaphthol and phenoselenazine derivative to achieve CPP.The photoactivated CPP in polystyrene(PS)film demonstrates a luminescence dissymmetry factor(glum),emission efficiency,and RTP lifetime up to 9.32×10^(–3),27.0%,and 40.0 ms,respectively.The remarkable sensitivity of PS film to oxygen and temperature enables the adjustable emission colors,ranging from green to offwhite and blue under varying conditions.The doping systems,utilizing hosts of triphenylphosphine and 9-phenylcarbazole,demonstrate an extended CPP lifetime of 85.9 ms and exhibit a persistent mechanoluminescence property with low pressure response threshold as low as 0.15 N.The information security provided by this CPP material was attained via the using of diverse emission colors and afterglow generated by distinct UV irradiation times and host materials.Alternately,it can also be achieved by observing different emission patterns using R-and L-polarizer.The research has presented a reliable approach for producing CPP materials with high emission efficiency and glum.