Themed collection Photon Upconversion Materials

Infrared (IR) to visible up-conversion devices made by incorporating IR detectors with visible emitting units are able to directly convert IR light into visible light.

Design principles of Cu(I) complexes to induce thermally activated delayed fluorescence (TADF) behaviour with an electron-rich carbene moiety are elucidated by means of time-resolved luminescence and high-quality quantum chemical calculations.

We synthesized a theranostics-integrated nanocomposite capable of switching between upconversion luminescence imaging and photothermal therapy/photodynamic therapy/NO gas therapy by changing the wavelength of near-infrared light irradiation.

Multifunctional core@shell type FeS₂@NaYF₄:Yb³⁺,Er³⁺ nanocomposites emit bright, color tunable UC photoluminescence and magnetic activity. We confirmed optical temperature sensing capability and rarely reported sensing of the laser power density.

A novel series of donor–acceptor–heavy-atom (D–A–H) molecules that simultaneously implement both photoinduced electron transfer and heavy atom effect strategies.

The role played by high concentration doping of Er³⁺ ions under 1550 nm excitation and the response mechanism of Ho³⁺ ions to 1550 nm photons.

Negative thermal expansion compounds provide an opportunity to understand the nature of thermal expansion and engineering applications of inorganic solid functional materials. This work gives a suitable case to investigate the relationship between thermal expansion and luminescence thermal behavior.

Giant enhancement of anti-quenching upconversion luminescence is achieved in the Sc₂W₃O₁₂:Er³⁺/Yb³⁺ phosphors by (KMg)³⁺ impurity doping, and the phosphors are used for the construction of an all-fiber temperature sensing system.

Fluorescent microspheres exhibit unique emissions at the microscale and have been widely used as probes for immunoassays and advanced micro-sensors.

A multimode high sensitivity fluorescence thermometer combining fluorescence thermal enhancement and FL thermal extension in one NTE material Y₂Mo₃O₁₂:Nd³⁺,Yb³⁺.

Er³⁺/Yb³⁺ are distributed in a double-layer structure, blocked by a single layer of Sc³⁺/La³⁺. Red UCL intensity of (Gd_0.8Er_0.1Yb_0.1)(La_0.9Sc_0.1)O₃ is comparable to β-NaYF₄:Er³⁺/Yb³⁺.

Solid-state green-to-blue upconversion is shown in organic–inorganic hybrid ureasil hosts using the palladium(II) octaethylporphyrin and diphenylanthracene sensitizer/emitter pair, with emission retained for >70 days without deoxygenation.

Because of their well-defined light–matter interaction volume, high-quality single-crystalline nature, and precise bandgap tunability, all-inorganic cesium lead halide (CsPbX₃ (X = Cl, Br, I)) perovskite (IHP) microplates are of fundamental and technological interest today.