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Flexible self‐healing thermal management devices are increasingly in demand due to their high flexibility, low driving voltage, and excellent stability of thermal property. In this paper, the design of mechanochromic self‐healing thermal management devices is reported based on photonic vitrimer through self‐healing dynamic covalent bond. A series of new photonic vitrimers i first prepared by dynamic disulfide covalent bond and PS@SiO2 photonic crystals. The resulting photonic vitrimer exhibits bright structural colors, large tensile strain (>1000%), high mechanical strength (>10 MPa) and self‐healing ability (>95% efficiency). More importantly, the structural color remains constant after 10000 stretching/releasing cycles, demonstrating excellent mechanical stability, creep‐resistance, and durability. Taking advantage of the above features, a novel mechanochromic flexible wireless thermal management (MFW) device is developed by semi‐embedding the photonic vitrimer in a thermally conductive carbon nanotube film and then integrating it with a Bluetooth module and a control chip. Interestingly, the MFW device exhibits mechanochromic property, fast thermal response, low driving voltage (103 °C, at 3 V), and precise temperature control. Notably, the device even remains electrothermal performance (105 °C) after self‐healing. This work provides new insight into the self‐healing photonic materials, and the device shows promising applications in wearable electronics, vitro physiotherapy, and personal heating. [ABSTRACT FROM AUTHOR]

The growing interest in mimicry of biological skins greatly promotes the birth of high‐performance artificial skins. Chameleon skins can actively transform environmental information into bioelectrical and color‐change signals simultaneously through manipulating ion transduction and photonic nanostructures. Here, inspired by chameleon skins, a novel biomimetic chromotropic photonic‐ionic skin (PI‐skin) capable of outputting synergistic electrical and optical signals under strain with robust adhesion, stability, and resilience is ingeniously constructed. The PI‐skin exhibits sensitive structural color change synchronized with electrical response via adjusting the lattice spacing of the photonic crystal (mechanochromic sensitivity: 1.89 nm per %, Δλ > 150 nm). Notably, the polyzwitterionic network provides abundant electrostatic interactions, endowing the PI‐skin with excellent adhesion, environmental tolerance, and outstanding mechanical stability (>10 000 continuous cycles). Meanwhile, the high loading of ionic liquid (IL) weakens the electrostatic interaction between the polyzwitterionic molecular chains, leading to high resilience. The PI‐skin is finally applied to construct a visually interactive wearable device, realizing precise human motion monitoring, remote communication, and visual localization of pressure distribution. This work not only expands design ideas for the construction of advanced biomimetic I‐skins but also provides a general optical platform for high‐level visual interactive devices and smart wearable electronics. [ABSTRACT FROM AUTHOR]

The integration of invisible photonic patterns into specific micro/nanostructures provides a new way to construct stimuli‐responsive optical anti‐counterfeiting devices. Herein, an innovative strategy for constructing highly invisible patterns in the solvent‐responsive double‐inverse‐opal (DIO) films by the thermal treatment is proposed. The masked area retains the responsive DIO structure, but the exposed area loses the periodic ordered array, which results in different optical responses of the pattern and background to the solvent. Due to the special structure, the scattering effect derived from the randomly distributed polystyrene microspheres within the pores of the inverse‐opal backbone in both the masked area and the exposed area makes the resultant film sample present a pale color, and the encrypted pattern is highly invisible in normal conditions. Interestingly, the hidden pattern can be quickly revealed by ethanol response, showing a large color contrast. Furthermore, reversible bilayer DIO films with multiple hidden patterns for advanced anti‐counterfeiting materials are prepared. Importantly, the as‐prepared film sample can reveal different patterns on the front and back sides in decryption, and simultaneously the overlapping part of the patterns can achieve color mixing based on the bilayer structure, thereby showing great potential in information encryption and anti‐counterfeiting fields. [ABSTRACT FROM AUTHOR]

Janus structure offers materials unique functionalities which are difficult to achieve otherwise with isotropic counterpart, opening up new avenues in diverse application fields. Here, a series of novel photonic Janus carbon fibers (PJCFs) with structural color gradient and excellent mechanical stability are reported by introducing 1D photonic layers with a gradient of periodicity. By virtue of the unique photonic architecture, the PJCFs exhibit a multiple and continuous variation of structural color (i.e., structural color gradient) in a full spectrum. By controlling the thickness of periodic layer, a series of PJCFs with vivid and tunable structural colors ranging from blue, green, orange, to violet‐red can be obtained. Furthermore, their gradient structural colors remain constant after reciprocating rubbing and laundering, showing outstanding mechanical robustness. Notably, benefiting from the inherent electrothermal property and flexibility of CFs, the PJCFs display stable Joule heating performance even under deformation. As proof‐of‐concept, the PJCFs are further integrated with wireless transmission system to construct a multicolored, wirelessly controlled thermal management device, realizing remote and precise temperature manipulation via Bluetooth. This work provides not only a new platform for achieving distinct structural color gradient of CFs, but also a promising strategy toward next‐generation multicolored personal healthcare devices. [ABSTRACT FROM AUTHOR]

Long noncoding RNA PVT1 is involved in the progression of female gynecological cancers. However, the role of PVT1 in ovarian granulosa cell apoptosis‐mediated premature ovarian insufficiency (POI) remains unclear. This study aims to elucidate the role of PVT1 in ovarian granulosa cell apoptosis‐mediated POI. The expression of PVT1 was compared between ovarian tissues from POI patients and normal controls. The methylation level in the PVT1 promoter region was detected by methylation‐specific polymerase chain reaction. The interaction between PVT1 and forkhead box class O3A (Foxo3a) was confirmed by RNA pull‐down and RNA immunoprecipitation assays. Granulosa cell apoptosis was detected using flow cytometry. The effect of PVT1 on transcription activity of Foxo3a was detected by luciferase reporter assay. The expression of PVT1 was low in the POI ovarian tissues compared with the controls, and such a low expression was related to the hypermethylation of the PVT1 promoter. PVT1 was localized in both the cytoplasm and the nucleus of granulosa cells. We determined that PVT1 could bind with Foxo3a and that downregulating PVT1 by small interfering RNAs inhibited Foxo3a phosphorylation by promoting SCP4‐mediated Foxo3a dephosphorylation, resulting in an increase in Foxo3a transcription activity. Moreover, downregulating PVT1 promoted granulosa cell apoptosis by increasing the Foxo3a protein levels. An in vivo experiment showed that the injection of PVT1 overexpressing vectors restored the ovarian function in POI mice. Hypermethylation‐induced downregulation of PVT1 promotes granulosa cell apoptosis in POI by inhibiting Foxo3a phosphorylation and increases the Foxo3a transcription activity. [ABSTRACT FROM AUTHOR]

Vitrimers, with their unique dynamic covalent bonds, possess attractive self‐healability and mechanical robustness, providing an intriguing opportunity to construct functional soft materials. However, their potential for function recovery, especially optical function, is underexplored. Harnessing the synergistic effect of photonic crystals and vitrimers, a novel photonic vitrimer with light regulating and self‐healing capabilities is presented. The resulting photonic vitrimer exhibits a large tensile strain (>1000%), high toughness (21.2 kJ m−3), bright structural color, and mechanochromism. Notably, the structural color remains constant even after 10 000 stretching/releasing cycles, showing superior mechanical stability, creep‐resistance, and excellent durability. More importantly, the exchange of dynamic covalent bonds imparts the photonic vitrimer with a self‐healing ability (>95% efficiency), enabling the recovery of its optical function. Benefiting from the above merits, the photonic vitrimer has been successfully used as a sensor for human motion detection, which demonstrates visualized interactive sensibility even after self‐repairing. This material design provides a general strategy for optical functionalization of vitrimers. The photonic vitrimer elastomers present great potential as resilient functional soft materials for diverse flexible devices and a novel optical platform for soft robotics, smart wearable devices, and human‐machine interaction. [ABSTRACT FROM AUTHOR]

Autosomal dominant hereditary polycystic kidney disease (ADPKD) is the most common inherited kidney disease that causes end‐stage renal disease and kidney failure. Preimplantation genetic testing for monogenic (PGT‐M) can effectively prevent the transmission of genetic diseases from parents to the offspring before pregnancy. However, PGT‐M currently adopts the single nucleotide polymorphism (SNP) linkage analysis for embryo's pathogenic gene carrying status and linkage analysis requires proband of the family. Here we report a new PGT‐M strategy using single sperm SNP linkage analysis for male patient with sporadic ADPKD caused by de novo PKD1 mutation. We recruited five couples with male patient with ADPKD caused by de novo PKD1 mutation, and 39 embryos from six PGT‐M cycles were detected. The five couples had at least one embryo that does not carry the PKD1 mutation. Within these five couples, the accuracy of carrier status of embryos was confirmed by amniotic fluid gene detection of two couples and two couples successfully delivered healthy fetuses. Therefore, the new PGT‐M strategy of using single sperm SNP linkage analysis was proved to be feasible and effective for male patient with ADPKD caused by de novo PKD1 mutation. [ABSTRACT FROM AUTHOR]

Mechanical nondiscoloring and antistretching photonic crystal (PC) films, especially those with stable structure colors during deformation, have great potential applications in wearable display devices, decoration, and packaging. Here, PC films with antistretching and invariant structural colors during deformation were prepared, by combining Zn2+ coordinated elastic material and hydroxypropyl methylcellulose (HPMC) with polystyrene@silica (PS@SiO2) colloidal crystals. The PC films release energy by forming local fractures at a microscopic level during the straining process but the lattice spacing and effective refractive index of the local array do not change. According to the Bragg law, the structure color remains unchanged. The introduction of HPMC gave the PC films excellent tensile properties, and the maximum tensile strength reached 10 MPa. And after 100 times of stretching, bending and compression cycles, the structural color remained unchanged. [ABSTRACT FROM AUTHOR]

Due to the increasing human mortality caused by natural disasters and traffic accidents, the development of smart traffic warning systems is urgent. The first smart indicator for traffic warning based on bilayer photonic crystals with both selective retroreflection and response reflection optical properties is developed. The wettability‐controlled reflection evaluates the risk of landslides and warns drivers to slow down, while the retroreflection simultaneously displays iridescent vivid structural colors to observers at different viewing directions relative to the illumination direction and informs drivers the approaching of the accident blackspot. The mechanism involves diffractions in the periodic nanostructures and uses the wettability of vertical surfaces to realize the spectral diversity of reflectance. Moreover, colorful flickering structural colors based on the rotational periodic diffraction and angle dependence of the retroreflection are designed for speed limits warning. It demonstrates an energy‐efficient, smart, and tunable multi‐functionalized bilayer photonic crystal that is especially suitable for nighttime traffic warning, advertisement, and periodic warning display applications. [ABSTRACT FROM AUTHOR]

Smart interactive electronic devices can dynamically respond to and visualize environmental stimuli. Inspired by the rapid color changes of natural creatures, an interactive electronic fiber sensor with high stretchability and tunable coloration is presented. It is based on an ingenious multi‐sheath design on a piezoresistive electronic fiber coupled with a mechanochromic photonic crystal microtubule. It has the unique capabilities of sensing and visualizing its deformation simultaneously, by reconstructing conductive paths and regulating the lattice spacing of the photonic sheath. In particular, it exhibits dynamic color switching spanning the full visible region (from red to blue), fast optical/electrical response (≈80 ms), and a large working range (0–200%), allowing its application as a user‐interactive sensor for dynamically monitoring large joint movements and muscle microvibrations of the human body in real time. This investigation provides a general platform for emerging interactive devices, which are promising for applications in wearable electronics, human–machine interactions, and intelligent robots. [ABSTRACT FROM AUTHOR]

TiO2/NaYF4:Yb3+,Er3+ nano-heterostructures are prepared in situ on the TiO2 photoanode of dye-sensitized solar cells (DSCs). Transmission electron microscopy (TEM) and high-resolution (HR)-TEM confirm the formation of TiO2/NaYF4:Yb3+,Er3+ nano-heterostructures. The up-converted fluorescence spectrum of the photoanode containing the nano-heterostructure confirms electron injection from NaYF4:Yb3+,Er3+ to the condution band (CB) of TiO2. When using a photoanode containing the nano-heterostructure in a DSC, the overall efficiency ( η) of the device is 17% higher than that of a device without the up-conversion nanoparticles (UCNPs) and 13% higher than that of a device containing mixed TiO2 and UCNPs. Nano-heterostructures of TiO2/NaYF4:Yb3+,Tm3+ and TiO2/NaYF4:Yb3+,Ho3+ can also be prepared in situ on TiO2 photoanodes. The overall efficiency of the device containing TiO2/NaYF4:Yb3+,Ho3+ nano-heterostructures is 15% higher than the control device without UCNPs. When nano-heterostructures of TiO2/NaYF4:Yb3+,Tm3+ are used, the open-circuit voltage ( Voc) and the short-circuit current density ( Jsc) are all slightly decreased. The effect of the different UCNPs results from the different energy levels of Er3+, Tm3+, and Ho3+. These results demonstrate that utilizing the UCNPs with the apporpriate energy levels can lead to effective electron injection from the UCNPs to the CB of TiO2, effectively improving the photocurrent and overall efficiency of DSCs while using NIR light. [ABSTRACT FROM AUTHOR]

Combining responsive colloidal photonic crystals into invisible wettability patterns is important in steganography and watermarking for information encoding and decoding. Using a bilayer photonic crystal as a regionally functionalized porous carrier, a dual‐responsive surface with tunable wettability, reversible switching between wetting and no wetting, and responsivity to pressure and solvents are reported. The mechanism of the design involves reversible switching of micropore shapes and optical diffraction in the fabricated periodic nanostructures, and uses the infiltration and capillary evaporation of fluids to realize the spectral diversity of reflectance. It generates different invisible wettability patterns that are regulated by induced pressure and the Donnan equilibrium osmotic pressure. Immersion of the sample in water induces the varying degrees of infiltration and immediately displays multiple colors. It enables instantaneously transparentizing the full infiltration parts of the top layer and simultaneously releasing the reflected light of the corresponding bottom layer. Moreover, those invisible patterns can be reset by wiping with ethanol. Multiple ways to encode and reveal invisible complex information can easily be realized due to these characteristics. This work opens a new avenue for encoding complex information in a single material platform and extends the design approach of invisible patterns for information coding. [ABSTRACT FROM AUTHOR]

Photonic‐ionic skins (PI‐skins) featuring multi‐signal synergistic outputs exhibit fascinating interactive sensing potential in flexible iononics. However, the existing ones are susceptible to irreversible damage in usage due to their poor toughness and deficiency in self‐healing. Herein, a novel tough mechanochromic PI‐skin is ingeniously constructed, from both molecular engineering and nanostructural engineering perspectives, via integrating the ordered photonic array and robust metal‐imidazole cross‐linked network. The PI‐skin displays synchronous structural color variation and sensitive electrical response under strain. Notably, the synergy of dense physical cross‐linking network and microphase‐separation structure achieved by strong metal‐imidazole coordination greatly promotes energy dissipation. PI‐skin possesses a combination of exceptional properties, including high fracture strength (8.22 MPa), remarkable toughness (10.23 MJ m−3), and robust adhesion behavior (2.30 MPa). Furthermore, favorable self‐healing capability at room temperature is realized thanks to the dynamic topological rearrangement of metal‐imidazole coordination. The PI‐skin demonstrates promising uses as a visually interactive wearable device for human motion monitoring and remote communication. This work not only broadens design considerations for the development of high‐performance artificial skins but also offers a general optical platform for high‐level interactive wearable devices. [ABSTRACT FROM AUTHOR]

Combining functional response materials into colloidal photonic crystals is an accepted encryption strategy for information security. Here, bilayer inverse heterostructure photonic crystals that enable instantaneously transparentizing of the top layer and simultaneously releasing the reflected light of the bottom layer when exposed to ethanol are reported. The transition can quickly return to its original state after the evaporation of ethanol. In addition, the bilayer film is responsive to water, which shows redshift of the bandgap position. The mechanism of the design involves optical scattering and diffraction in the fabricated periodic nanostructures and uses the infiltration and capillary evaporation of fluids with low surface tension to realize the spectral diversity of reflectance. The effects of scattering and color superposition of the upper layer can be obliterated and re‐established for the fact of the infiltration and capillary evaporation of fluids with low surface tension; meanwhile, it provisionally displays the pattern of the bottom layer. Multiple reversible ways to hide and display information could be easily realized by these characteristics. Reconfigurable bilayer inverse heterostructure photonic crystals simultaneously provide a simple and sensitive optical technique for investigating the intriguing encryption effects at the nanoscale. [ABSTRACT FROM AUTHOR]

Supramolecular elastomers have attracted extensive attention due to their excellent mechanical properties. Herein, inspired by the concept of a dual cross‐linked network structure, a dual‐component coordination supramolecular elastomer is prepared via photopolymerization of three monomers combined with zinc ion (Zn2+)‐crosslinked low molecular weight polyacrylic acid (PAA). The covalent network of three monomers serves as a soft component forming the supporting network. The network of Zn2+ crosslinked low molecular weight PAA forms the hard component. The covalent network is crosslinked and locked by the coordinated network. This compact network contributes to improving the comprehensive mechanical properties. The optimal elastomer is that the molar ratio of carboxylic of low molecular weight PAA with Zn2+ is 1:0.5. The tensile and compression stress of the optimal elastomer are 4.08 and 6.90 MPa, respectively. The loading–unloading cycles can reach 1000 times without fracture. The self‐recovery ratios of the tensile and compression modes reaches 80% and 95%, respectively. [ABSTRACT FROM AUTHOR]

Photon upconversion of oxides nanomaterials have attracted broad attentions on account of their high stability and cost‐effective fabrication process. However, the relative low emission intensity caused by nonradiative decay severely limits their applications. Here, a new strategy to enhance upconversion emission of oxides through vanadium sensitization is reported, in which efficient emissions can be achieved via Yb–VO43− dimer‐mediated energy migration for a wide range of lanthanide activators (including Er, Tm, Ho, Eu, and Nd) in Yb3Al5O12 system. Interestingly, the resulting oxide nanocrystals demonstrate remarkable upconversion enhancement compared with their vanadium‐undoped counterparts, for example, an enhancement factor of 580 is reached for green emission of Er. More importantly, efficient upconversion luminescence can be realized for the activators (such as Eu and Nd ions) without long‐lived intermediary energy states. Considering the demonstration of in vivo bioimaging by using these nanocrystals after surface modification, it is anticipated that these results can bring new opportunities to oxide upconversion nanomaterials in bioassay, therapy, sensing, and other aspects. A new strategy to enhance upconversion emission of oxide through vanadium sensitization is demonstrated. Interestingly, several hundred times enhancement can be achieved in a collection of lanthanide ions including Er, Tm, Ho, Eu, and Nd ions via a Yb–VO43− dimer‐mediated energy migration procedure, showing promising application for in vivo upconverting imaging. [ABSTRACT FROM AUTHOR]