Fabrication of Spherical Multi-Hollow TiO₂ Nanostructures for Photoanode Film with Enhanced Light-Scattering Performance

Spherical multihollow (MH) TiO₂ nanostructures have been synthesized via a microemulsion-based approach with titanium glycerolate complexes formation at glycerol microemulsions interface. The self-aggregation of those microemulsions induces the formation of MH TiO₂ nanospheres. Owing to this hierarchical hollow structure, photoanode films derived from MH TiO₂ nanosphere as light scattering layer exhibits an enhanced light harvesting efficiency, thus leading to a 43% increment of photovoltaic performance compared to that from P25 nanoparticle film

Construction of Multifunctional Hydrogels via a Supramolecular Self-Assembled Strategy with Ultrahigh Sensitivity to Strain Responsiveness

Intelligent electronic devices have been diffusely used in health detection, energy storage, and biomedicine based on their autonomy, flexibility, and adaptive improvement, but traditional materials have the drawbacks of limited flexibility, instability, and inadequate reusability. Herein, poly(acrylic acid)-based hydrogels with efficient self-healing performance and high-precision sensing performance were constructed by a supramolecular self-assembled strategy based on electrostatic interactions, metal coordination, and hydrogen bonds. This hydrogel exhibited a tensile strength of 102.9 kPa and an elongation at break of 990% with good fatigue resistance and self-recovery ability. The hydrogel also displayed good light transmission and UV-shielding effects, as well as good adhesion ability on different materials. Besides, the hydrogel had an electrical conductivity of 0.98 S/m, which could light up a light-emitting diode (LED) bulb when connected in a circuit. Based on these great features, the hydrogel exhibited ultrahigh sensitivity with gauge factor values of 4.00 and 17.00 within the strain ranges of 0–200 and 600–800%, respectively. The hydrogel could be applied not only for large human movements but also for detecting subtle movements. Most importantly, the hydrogel exhibited a great self-healing property, which could almost self-heal within 6 h with a healing efficiency of 99%. Therefore, this work provides a multifunctional hydrogel construction method, and the prepared hydrogels displayed great potential application in the strain sensor field

Construction of Multifunctional Hydrogels via a Supramolecular Self-Assembled Strategy with Ultrahigh Sensitivity to Strain Responsiveness

Intelligent electronic devices have been diffusely used in health detection, energy storage, and biomedicine based on their autonomy, flexibility, and adaptive improvement, but traditional materials have the drawbacks of limited flexibility, instability, and inadequate reusability. Herein, poly(acrylic acid)-based hydrogels with efficient self-healing performance and high-precision sensing performance were constructed by a supramolecular self-assembled strategy based on electrostatic interactions, metal coordination, and hydrogen bonds. This hydrogel exhibited a tensile strength of 102.9 kPa and an elongation at break of 990% with good fatigue resistance and self-recovery ability. The hydrogel also displayed good light transmission and UV-shielding effects, as well as good adhesion ability on different materials. Besides, the hydrogel had an electrical conductivity of 0.98 S/m, which could light up a light-emitting diode (LED) bulb when connected in a circuit. Based on these great features, the hydrogel exhibited ultrahigh sensitivity with gauge factor values of 4.00 and 17.00 within the strain ranges of 0–200 and 600–800%, respectively. The hydrogel could be applied not only for large human movements but also for detecting subtle movements. Most importantly, the hydrogel exhibited a great self-healing property, which could almost self-heal within 6 h with a healing efficiency of 99%. Therefore, this work provides a multifunctional hydrogel construction method, and the prepared hydrogels displayed great potential application in the strain sensor field

Versatile Synthesis of Multiarm and Miktoarm Star Polymers with a Branched Core by Combination of Menschutkin Reaction and Controlled Polymerization

Menschutkin reaction and controlled polymerization were combined to construct three types of star polymers with a branched core. Branched PVD was synthesized by reversible addition–fragmentation chain transfer (RAFT) copolymerization and used as a core reagent to synthesize multiarm and miktoarm stars with poly­(ε-caprolactone) (PCL), polystyrene, poly­(methyl methacrylate), poly­(<i>tert</i>-butyl acrylate), and poly­(<i>N</i>-isopropylacrylamide) segments. Effects of reaction time, feed ratio, and arm length on coupling reaction between PVD and bromide-functionalized polymer were investigated, and a variety of A_<i>m</i>-type stars (<i>m</i> ≈ 7.0–35.1) were obtained. Meanwhile, A_<i>m</i>B_<i>n</i> stars (<i>m</i> ≈ 9.0, <i>n</i> ≈ 6.1–11.3) were achieved by successive Menschutkin reactions, and A_<i>m</i>C_<i>o</i> stars (<i>m</i> ≈ 8.8–9.0, <i>o</i> ≈ 5.0) were generated by tandem quaternization and RAFT processes. Molecular weights of various stars usually agreed well with the theoretical values, and their polydispersity indices were in the range of 1.06–1.24. The arm number, chain length, and chemical composition of star polymers could be roughly adjusted by control over reaction conditions and utilization of alternative methods, revealing the generality and versatility of these approaches. These ion-bearing stars were liable to exhibit solubility different from normal covalently bonded polymers, and the chain relaxation and melting behaviors of polymer segments were strongly dependent on the macromolecular architecture

Construction of Multifunctional Hydrogels via a Supramolecular Self-Assembled Strategy with Ultrahigh Sensitivity to Strain Responsiveness

Intelligent electronic devices have been diffusely used in health detection, energy storage, and biomedicine based on their autonomy, flexibility, and adaptive improvement, but traditional materials have the drawbacks of limited flexibility, instability, and inadequate reusability. Herein, poly(acrylic acid)-based hydrogels with efficient self-healing performance and high-precision sensing performance were constructed by a supramolecular self-assembled strategy based on electrostatic interactions, metal coordination, and hydrogen bonds. This hydrogel exhibited a tensile strength of 102.9 kPa and an elongation at break of 990% with good fatigue resistance and self-recovery ability. The hydrogel also displayed good light transmission and UV-shielding effects, as well as good adhesion ability on different materials. Besides, the hydrogel had an electrical conductivity of 0.98 S/m, which could light up a light-emitting diode (LED) bulb when connected in a circuit. Based on these great features, the hydrogel exhibited ultrahigh sensitivity with gauge factor values of 4.00 and 17.00 within the strain ranges of 0–200 and 600–800%, respectively. The hydrogel could be applied not only for large human movements but also for detecting subtle movements. Most importantly, the hydrogel exhibited a great self-healing property, which could almost self-heal within 6 h with a healing efficiency of 99%. Therefore, this work provides a multifunctional hydrogel construction method, and the prepared hydrogels displayed great potential application in the strain sensor field

Construction of Multifunctional Hydrogels via a Supramolecular Self-Assembled Strategy with Ultrahigh Sensitivity to Strain Responsiveness

Intelligent electronic devices have been diffusely used in health detection, energy storage, and biomedicine based on their autonomy, flexibility, and adaptive improvement, but traditional materials have the drawbacks of limited flexibility, instability, and inadequate reusability. Herein, poly(acrylic acid)-based hydrogels with efficient self-healing performance and high-precision sensing performance were constructed by a supramolecular self-assembled strategy based on electrostatic interactions, metal coordination, and hydrogen bonds. This hydrogel exhibited a tensile strength of 102.9 kPa and an elongation at break of 990% with good fatigue resistance and self-recovery ability. The hydrogel also displayed good light transmission and UV-shielding effects, as well as good adhesion ability on different materials. Besides, the hydrogel had an electrical conductivity of 0.98 S/m, which could light up a light-emitting diode (LED) bulb when connected in a circuit. Based on these great features, the hydrogel exhibited ultrahigh sensitivity with gauge factor values of 4.00 and 17.00 within the strain ranges of 0–200 and 600–800%, respectively. The hydrogel could be applied not only for large human movements but also for detecting subtle movements. Most importantly, the hydrogel exhibited a great self-healing property, which could almost self-heal within 6 h with a healing efficiency of 99%. Therefore, this work provides a multifunctional hydrogel construction method, and the prepared hydrogels displayed great potential application in the strain sensor field

Construction of Multifunctional Hydrogels via a Supramolecular Self-Assembled Strategy with Ultrahigh Sensitivity to Strain Responsiveness

Intelligent electronic devices have been diffusely used in health detection, energy storage, and biomedicine based on their autonomy, flexibility, and adaptive improvement, but traditional materials have the drawbacks of limited flexibility, instability, and inadequate reusability. Herein, poly(acrylic acid)-based hydrogels with efficient self-healing performance and high-precision sensing performance were constructed by a supramolecular self-assembled strategy based on electrostatic interactions, metal coordination, and hydrogen bonds. This hydrogel exhibited a tensile strength of 102.9 kPa and an elongation at break of 990% with good fatigue resistance and self-recovery ability. The hydrogel also displayed good light transmission and UV-shielding effects, as well as good adhesion ability on different materials. Besides, the hydrogel had an electrical conductivity of 0.98 S/m, which could light up a light-emitting diode (LED) bulb when connected in a circuit. Based on these great features, the hydrogel exhibited ultrahigh sensitivity with gauge factor values of 4.00 and 17.00 within the strain ranges of 0–200 and 600–800%, respectively. The hydrogel could be applied not only for large human movements but also for detecting subtle movements. Most importantly, the hydrogel exhibited a great self-healing property, which could almost self-heal within 6 h with a healing efficiency of 99%. Therefore, this work provides a multifunctional hydrogel construction method, and the prepared hydrogels displayed great potential application in the strain sensor field

Synthesis and Properties of Multicleavable Amphiphilic Dendritic Comblike and Toothbrushlike Copolymers Comprising Alternating PEG and PCL Grafts

Facile construction of novel functional dendritic copolymers by combination of self-condensing vinyl polymerization, sequence-controlled copolymerization and RAFT process was presented. RAFT copolymerization of a disulfide-linked polymerizable RAFT agent and equimolar feed ratio of styrenic and maleimidic macromonomers afforded multicleavable A_<i>m</i>B_<i>n</i> dendritic comblike copolymers with alternating PEG (A) and PCL (B) grafts, and a subsequent chain extension polymerization of styrene, <i>tert</i>-butyl acrylate, methyl methacrylate, and <i>N</i>-isopropylacrylamide gave A_<i>m</i>B_<i>n</i>C_<i>o</i> dendritic toothbrushlike copolymers. (PEG)_<i>m</i>(PCL)_<i>n</i> copolymers obtained were of adjustable molecular weight, relatively low polydispersity (PDI = 1.10–1.32), variable CTA functionality (<i>f</i>_CTA = 4.3–7.5), and similar segment numbers of PEG and PCL grafts, evident from ¹H NMR and GPC-MALLS analyses. Their branched architecture was confirmed by (a) reduction-triggered degradation, (b) decreased intrinsic viscosities and Mark–Houwink–Sakurada exponent than their “linear” analogue, and (c) lowered glass transition and melting temperatures and broadened melting range as compared with normal A_<i>m</i>B_<i>n</i> comblike copolymer. In vitro drug release results revealed that the drug release kinetics of the disulfide-linked A_<i>m</i>B_<i>n</i> copolymer aggregates was significantly affected by macromolecular architecture, end group and reductive stimulus. These stimuli-responsive and biodegradable dendritic copolymer aggregates had a great potential as controlled delivery vehicles

PAMAM Dendrimer-Baculovirus Nanocomplex for Microencapsulated Adipose Stem Cell-Gene Therapy: <i>In Vitro</i> and <i>in Vivo</i> Functional Assessment

The present study aims to develop a new stem cell based gene delivery system consisting of human adipose tissue derived stem cells (hASCs) genetically modified with self-assembled nanocomplex of recombinant baculovirus and PAMAM dendrimer (Bac-PAMAM) to overexpress the vascular endothelial growth factor (VEGF). Cells were enveloped into branched PEG surface functionalized polymeric microcapsules for efficient transplantation. <i>In vitro</i> analysis confirmed efficient transduction of hASCs expressing 7.65 ± 0.86 ng functionally active VEGF per 10⁶ microencapsulated hASCs (ASC-VEGF). To determine the potential of the developed system, chronically infarcted rat hearts were treated with either empty microcapsules (MC), microencapsulated hASCs expressing MGFP reporter protein (MC+ASC-MGFP), or MC+ASC-VEGF, and analyzed for 10 weeks. Post-transplantation data confirmed higher myocardial VEGF expressions with significantly enhanced neovasculature in the MC+ASC-VEGF group. In addition, the cardiac performance, as measured by percentage ejection fraction, also improved significantly in the MC+ASC-VEGF group (48.6 ± 6.1%) compared to that in MC+ASC-MGFP (38.8 ± 5.3%) and MC groups (31.5 ± 3.3%). Collectively, these data demonstrate the feasibility of this system for improved stem cell therapy applications

Revealing the Structure–Luminescence Relationship in Robust Sn(IV)-Based Metal Halides by Sb³⁺ Doping

Low-dimensional hybrid metal halides are an emerging class of materials with highly efficient photoluminescence (PL), but the problems of poor stability remain challenging. Sn(IV)-based metal halides show robust structure but exhibit poor PL properties, and the structure–luminescence relationship is elusive. Herein, two Sn(IV)-based metal halides (compounds 1 and 2) with the same constituent ((C6H16N2)SnCl6) but different crystal structures have been prepared, which however show poor PL properties at room temperature due to the absence of active ns2 electrons. To improve materials’ PL properties, Sb3+ with active 5s2 electrons was embedded into the lattice of Sn4+-based hosts. As a result, efficient emissions were achieved for Sb3+-doped compounds 1 and 2 with a maximum PL efficiency of 14.28 and 62%, respectively. Experimental and calculation results reveal that the smaller distorted lattice structure of the host could result in the blueshift of the emission from Sb3+. Thus, a tunable color from red to orange was realized. Benefiting from the broadband efficient emission from Sb3+-doped compound 2, an efficient white light-emitting diode with a high color rendering index of up to 92.3 was fabricated to demonstrate its lighting application potential. This work promotes the understanding of the influence of robust Sn(IV)-based host lattice on the PL properties of Sb3+, advancing the development of environmentally friendly, low-cost, and high-efficiency Sn(IV)-based metal halides