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Ni1Co3@PDA nanosheets were utilized as photothermal materials in a kerosene lamp-like evaporator for solar steam generation. A high evaporation rate of 2.42 kg m−2 h−1 with a corresponding energy efficiency beyond the theoretical limit was achieved.

Organic photodetectors with UV‐sensitivity are of great potential for various optoelectronic applications. Integration of high charge carrier mobility, long exciton diffusion length as well as unique UV‐sensitivity for active materials is crucial for construction of UV‐sensitive devices with high performance, however, very few organic semiconductors can integrate these properties simultaneously. Herein, two novel organic semiconductors containing large steric hindrance triphenylamine groups, 1,6‐distriphenylamineethynylpyrene (1,6‐DTEP) and 2,7‐distriphenylamineethynylpyrene (2,7‐DTEP) are designed and synthesized. It demonstrates that the single crystals of both 1,6‐DTEP and 2,7‐DTEP exhibit superior integrated optoelectronic properties of high charge carrier mobility, unique UV absorption, high photoluminescence quantum yields as well as small exciton binding energies. Organic phototransistors constructed using 1,6‐DTEP and 2,7‐DTEP single crystals show ultrasensitive performance with ultra‐high photoresponsivity of 2.86 × 106 and 1.04 × 105 A W−1, detectivity (D*) of above 1.49 × 1018 and 5.28 × 1016 Jones under 370 nm light illumination, respectively. It indicates the great potential of 1,6‐DTEP and 2,7‐DTEP‐based phototransistors for organic UV‐photodetector applications and also provides a new design strategy to develop series of better performance UV photoelectric organic materials for related research in organic optoelectronics.

Rare-earth-ion-doped upconversion (UC) nanoparticles have generated considerable interest because of their potential application in solar cells, biological labeling, therapeutics, and imaging. However, the applications of UC nanoparticles were still limited because of their low emission efficiency. Photonic crystals and noble metal nanoparticles are applied extensively to enhance the UC emission of rare earth ions. In the present work, a novel substrate consisting of inverse opal photonic crystals and Ag nanoparticles was prepared by the template-assisted method, which was used to enhance the UC emission of NaYF4: Yb(3+), Er(3+) nanoparticles. The red or green UC emissions of NaYF4: Yb(3+), Er(3+) nanoparticles were selectively enhanced on the inverse opal substrates because of the Bragg reflection of the photonic band gap. Additionally, the UC emission enhancement of NaYF4: Yb(3+), Er(3+) nanoparticles induced by the coupling of metal nanoparticle plasmons and photonic crystal effects was realized on the Ag nanoparticles included in the inverse opal substrate. The present results demonstrated that coupling of Ag nanoparticle with inverse opal photonic crystals provides a useful strategy to enhance UC emission of rare-earth-ion-doped nanoparticles.

Metal nanoparticle plasmons or the photonic crystal effect are being widely used to modify luminescence properties of materials. However, coupling of surface plasmons with photonic crystals are seldom reported for enhancing luminescence of materials. In this paper, a new method for upconversion emission enhancement of rare-earth doped nanoparticles is reported, attributed to the coupling of surface plasmons with photonic band gap effects. Opal/Ag hybrid substrates were prepared by depositing Ag nanoparticles on the top layer of opals by magnetron sputtering. The selective enhancement of red or green upconversion emission of NaYF4:Yb3+,Er3+ nanoparticles on the opal/Ag hybrid substrates is attributed to the coupling effect of surface plasmons and Bragg reflection of the photonic band gap. In addition, the upconversion emission enhancement of NaYF4:Yb3+,Er3+ nanoparticles on the opal/Ag hybrid substrate is attributed to the excitation enhancement was obtained when the excitation light wavelengths overlap with the photonic band gaps of opal/Ag hybrid substrates. We believe that these enhancement effects based on the coupling of metal nanoparticles with the photonic band gap could be extended to other light-emitting materials, which may result in a new generation of lighting devices.

Investigations on the relationship between multi-stimuli responsive luminescent properties and aggregation structures of polymorphs play a crucial role in developing organic multi-stimuli responsive luminescent (OMSRL) materials.

An interfacial gelation coating method is developed to selectively coat photothermal materials on 3D substrate surfaces which dramatically reduces the consumption of photothermal materials while delivering superior performance in solar evaporation.