To develop high-performance thermally activated delayed fluorescence (TADF) exciplex emitters, a novel strategy of introducing a single-molecule TADF emitter as one of the constituting materials has been presented. Such a new type of exciplex TADF emitter will have two reverse intersystem crossing (RISC) routes on both the pristine TADF molecules and the exciplex emitters, benefiting the utilization of triplet excitons. Based on a newly designed and synthesized single-molecule TADF emitter MAC, a highly efficient exciplex emitter MAC:PO-T2T has been obtained. The device based on MAC:PO-T2T with a weight ratio of 7:3 exhibits a low turn-on voltage of 2.4 V, high maximum efficiency of 52.1 cd A⁻¹ (current efficiency), 45.5 lm W⁻¹ (power efficiency), and 17.8% (external quantum efficiency, EQE), as well as a high EQE of 12.3% at a luminance of 1000 cd m⁻². The device shows the best performance among reported organic light-emitting devices based on exciplex emitters. Such high-efficiency and low-efficiency roll-off should be ascribed to the additional reverse intersystem crossing process on the MAC molecules, showing the advantages of the strategy described in this study.

The detection of anions in pure water phase with colorimetric sensor is a long standing challenge. As one of the most important anions, F^– is associated with nerve gases and the refinement of uranium for nuclear weapons. However, limited by its anions nature, few of the reported colorimetric sensors can successfully applied to detect F^–1 in pure water phase. This work designs a colorimetric sensor for F^–1 pure water phase detection by taking the advantages of the strong specific binding between F and Si, as well as the color-changing property of H-terminated Si nanowires (SiNWs). The sensor demonstrates ultra-sensitivity, high selectivity, and good stability. The results reveal particular interest for the development of new type aqueous phase anions sensors with SiNWs.

As an interesting layered material, molybdenum disulfide (MoS₂) has been extensively studied in recent years due to its exciting properties. However, the applications of MoS₂ in optoelectronic devices are impeded by the lack of high-quality p–n junction, low light absorption for mono-/multilayers, and the difficulty for large-scale monolayer growth. Here, it is demonstrated that MoS₂ films with vertically standing layered structure can be deposited on silicon substrate with a scalable sputtering method, forming the heterojunction-type photodetectors. Molecular layers of the MoS₂ films are perpendicular to the substrate, offering high-speed paths for the separation and transportation of photo-generated carriers. Owing to the strong light absorption of the relatively thick MoS₂ film and the unique vertically standing layered structure, MoS₂/Si heterojunction photodetectors with unprecedented performance are actualized. The self-driven MoS₂/Si heterojunction photodetector is sensitive to a broadband wavelength from visible light to near-infrared light, showing an extremely high detectivity up to ≈10¹³ Jones (Jones = cm Hz^1/2 W⁻¹), and an ultrafast response speed of ≈3 μs. The performance is significantly better than the photodetectors based on mono-/multilayer MoS₂ nanosheets. Additionally, the MoS₂/Si photodetectors exhibit excellent stability in air for a month. This work unveils the great potential of MoS₂/Si heterojunction for optoelectronic applications.

Combination of chemotherapy and photothermal therapy is considered to be a promising strategy for the next generation of cancer treatments. However, it has been limited by difficulties in obtaining high drug payload chemo-photothermal agents, and thus complete destruction of tumor without recurrence has never been achieved, unless they are conjugated with some targeting ligands for special targeted drug delivery. Herein, iron oxide nanoparticle (IONP)-doped 10-hydroxycamptothecin drug nanorods (HCPT NRs), with an organic conducting polymer poly(4-styrenesulfonate) (PEDOT) coating outside, are developed for cancer diagnosis and chemo-photothermal therapy. The drug-loading capacity of HCPT in the complex NRs reaches up to 72%, which is much higher than previously reported carrier-based nanocomposites. In vitro studies show that the resulting NRs demonstrate an excellent chemo-photothermal synergistic effect for tumor ablation. More importantly, 100% in vivo tumor elimination is achieved under a low laser power density of 1 W cm⁻² without weight loss and tumor recurrence. Moreover, IONP endow these drug nanocomposites with imaging capabilities, thus rendering the resulting HCPT-PEDOT NR an all-in-one processing system for diagnosis and treatment with low systematic toxicity.

Gold (Au)-nanoshelled 10-hydroxycamptothecin nanoparticles (HCPT NPs) are developed with combination of photothermal therapy and chemotherapy for highly effective cancer therapy. The strong near-infrared (NIR) absorbance from Au nanoshells endows the nanocomposites photothermal effects and on-demand drug release. Notably, the drug-loading content reaches up to 63.7 wt%, which is much higher than that in the previously reported nanovehicles systems. Both in vitro and in vivo studies indicate that the combined local specific chemotherapy with external NIR photothermal therapy demonstrates a synergistic effect, which is significantly better than either of them alone. More importantly, due to the high drug-loading content and efficient photothermal effects of the nanocomposites, 100% in vivo tumor elimination is achieved at a low laser irradiation power density of 1 W cm⁻² without weight loss and tumor recurrence. No obvious systematic toxicity is observed for the injected mice, indicating the good biocompatibility of this kind of multifunctional drug nanocomposites. This work highlights the great potential of drug–nanostructure-based multifunctional core/shell nanpocomposite for highly efficient cancer therapy.

A blue fluorescent compound, 9-[4-(4,6-diphenoxy-1,3,5-triazin-2-yl)phenyl]-9H-carbazole (POTC), the triplet energy level of which reaches 2.76 eV, has been designed and synthesized. POTC is an excellent blue emitter as well as host for green and red phosphors, and therefore, matches the requirements of the host for single-emitting-layer fluorescence and phosphorescence hybrid white organic light-emitting diodes (OLEDs). The blue, green, red, and white devices based on POTC show maximum external quantum efficiencies (EQEs) of 2.4, 22.4, 13.0, and 8.1 %, respectively. Even at a high brightness of 1000 cd m⁻², these values maintain EQEs of 2.3, 22.1, 11.1, and 7.0 %, respectively, indicating less than 15 % roll-offs from the maxima.

Multifunctional donor–acceptor compound 4,4′-bis(dibenzothiophene-S,S-dioxide-2-yl)triphenylamine (DSTPA) was obtained by linking a strongly electron-withdrawing core and a strongly electron-donating core with a biphenyl bridge in linear spatial alignment. DSTPA not only has suitable HOMO and LUMO levels for easily accepting both holes and electrons, it was also demonstrated to have a high fluorescence quantum yield of 0.98 and a high triplet energy level of 2.39 eV. Versatile applications of DSTPA for bipolar transport, green fluorescent emission, and sensitizing a red phosphor were systematically investigated in a series of multi- and single-layer organic light-emitting devices. In traditional multilayer devices, it shows excellent performance both in an undoped fluorescent device (used as a green emitter and achieving maximum current and power efficiencies (CE and PE) of 12.6 cd A⁻¹ and 9.4 Lm W⁻¹, respectively) and in a red phosphorescent device (used as a host and achieving maximum CE and PE of 26.4 cd A⁻¹ and 26.3 Lm W⁻¹, respectively). Furthermore, DSTPA was also simultaneously used as an emitter, a hole transporter, and an electron transporter in a single-layer device showing CE and PE of 5.1 cd A⁻¹ and 4.7 Lm W⁻¹, respectively. A single-layer red phosphorescent device with efficiencies of 11.7 cd A⁻¹ and 12.6 Lm W⁻¹ was obtained by doping DSTPA with a red phosphor. The performances of all of the devices in this work are comparable to the best of their corresponding classes in the literature.

Organic one-dimensional nanostructures are attractive building blocks for electronic, optoelectronic, and photonic applications. Achieving aligned organic nanowire arrays that can be patterned on a surface with well-controlled spatial arrangement is highly desirable in the fabrication of high-performance organic devices. We demonstrate a facile one-step method for large-scale controllable patterning growth of ordered single-crystal C₆₀ nanowires through evaporation-induced self-assembly. The patterning geometry of the nanowire arrays can be tuned by the shape of the covering hats of the confined curve-on-flat geometry. The formation of the pattern arrays is driven by a simple solvent evaporation process, which is controlled by the surface tension of the substrate (glass or Si) and geometry of the evaporation surface. By sandwiching a solvent pool between the substrate and a covering hat, the evaporation surface is confined to along the edge of the solvent pool. The geometry of the formed nanowire pattern is well defined by a surface-tension model of the evaporation channel. This simple method is further established as a general approach that is applicable to two other organic nanostructure systems. The I–V characteristics of such a parallel, organic, nanowire-array device was measured. The results demonstrate that the proposed method for direct growth of nanomaterials on a substrate is a feasible approach to device fabrication, especially to the fabrication of the parallel arrays of devices.