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Two-dimensional transition metal dichalcogenides are of particular interest in high-performance photothermal conversion, yet there remains a huge challenge in their practical application in smart textiles for healthcare, energy, and personal protection. Herein, we controllably prepared MoS2 hollow nanospheres with a high photothermal conversion efficiency of 36% via a microemulsion-hydrothermal method, which was further applied to construct photothermal fibers for personal thermal management after a hot-blast dip-drying process. Because of the prominent photothermal effect, the temperature of the photothermal fibers sharply increases from the room temperature value of 25.0 to 55.5 °C in 60 s under near-infrared illumination with a power density of 500 W/cm2. Furthermore, the photothermal fiber pad demonstrated an obvious temperature enhancement of 38.0 °C from a skin temperature of 22.0 °C after it was irradiated by natural sunlight for 60 s. Significantly, the antibacterial elimination rates of the photothermal fibers for Escherichia coli and Staphylococcus aureus are ∼99.9 and ∼99.8%, respectively. This strategy affords an avenue toward the practical application of photothermal materials in smart fibers for personal thermoregulation.

The controlled preparation of two-dimensional (2D) nanomaterials exhibiting heterojunction structures based on nontoxic and economical transition metal oxides represents breakthroughs in the electr...

The realization of high-performance optoelectronic devices requires excellent charge-transporting layers and efficient carrier recombination. Herein, we synthesized cesium tungsten bronze (Cs0.32WO3) nanocrystals and utilized them as the hole-transporting material to fabricate all-inorganic perovskite light-emitting diodes (PeLEDs). Due to the excellent carrier balance characteristics via comparison between the hole-only device and electron-only device, the all-inorganic PeLEDs with CsPbBr3 as the light-emitting layer present the maximum current efficiency of 31.51 cd/A and external quantum efficiency (EQE) of 8.48%, which are self-evidently enhanced compared with the PEDOT:PSS (14.78 cd/A, 4.03%) and WO3 (24.75 cd/A, 6.18%) based devices. Considering the remarkably improved device performance, the proposed HTL of Cs0.32WO3 is promising, acting as a favorable building block for high-efficiency light-emitting devices.

Organic heterostructured micro-/nanomaterials (OHTMs) integrating heterostructured advantages and organic material character have drawn strong attention in nanoscience and nanotechnology to meet th...

Organic-inorganic halide perovskite solar cells (PSCs) still suffer from stability issues which are caused by possible erosions from moisture, ultraviolet (UV) light, heat, and so forth. An electron-transporting layer (ETL), that is, TiO2, is a key component for state-of-the-art PSCs. However, UV-caused desorption of O2- in TiO2 would accelerate the degradation of PSCs. Herein, we explored perovskite oxide, NaTaO3, for the first time as an alternative ETL in PSCs. NaTaO3 as an ETL can effectively avoid the damage from UV irradiation, inhibit the degradation of the perovskite layer, and improve the overall stability of the PSC. PSCs fabricated with NaTaO3 yielded a power conversion efficiency (PCE) of 21.07% with a retention of more than 80% of this initial PCE after 240 min UV irradiation in air while the reference device with a PCE of 20.16% can only retain about 53% of its initial PCE after the same testing condition. The developed stable perovskite oxide material of NaTaO3 provides the diversification of electron-selective contact for highly efficient and stable PSCs.

Two-dimensional (2D) organic crystals with significant advantages, such as high crystallinity, well-defined shape, and dimension-dependent optical properties, have been widely investigated in recen...

Carbon dots (CDs) that exhibit emission over the whole visible spectrum are desired for use in light-emitting diodes (LEDs). Here, CDs displaying tunable fluorescence over the whole visible region are synthesized. Different concentrations of CDs are uniformly dispersed in epoxy resin and coated on 405 nm LED chips to obtain monochrome blue, cyan, green, yellow, red, and deep red LEDs that yield a color gamut covering 99.4% of the National Television Standards Committee (NTSC) standard. These monochrome LEDs display similar high stability. Furthermore, warm and neutral white LEDs are produced by coating cyan- and red-emitting CD layers on 405 nm LED chips, achieving color-rendering indexes (CRIs) of 96.4 and 96.6, respectively. Two fluorescent conversion layers derived from one material at different concentrations simplify the preparation of high-CRI white LEDs. The uniform weak changes of the cyan and red photoluminescence peaks during operation ensure the high stability of these CD-based white LEDs. This research provides a new avenue to develop low-cost, easy-to-prepare CDs with tunable emission colors as alternative phosphors for LED-based high-performance displays and lighting.

Full inorganic cesium lead halide perovskites (IOPs) are regarded as attractive candidates for light-emitting diodes (LEDs) by their excellent luminescent conversion. However, unsatisfactory efficiency and stability are still the main drawbacks that hinder the commercialization progress of perovskite LEDs (PeLEDs). Here, we report an extremely uniform and flat CsPbBr3 film composing of self-assembly core–shell structured quantum dots (SCQDs) based on one-step precursor coating. The QDs size in the CsPbBr3 film is around 4.5 nm (smaller than the Bohr radius), which significantly confines injected carriers and leads to a ultrahigh exciton binding energy (Eb) of 198 meV. In addition, unfavorable surfacial defects are dramatically passivated by a thin surfacial-capping layer composed of long-chain ammonium groups (phenylalanine bromide, PPABr), resulting in an ultralow nonradiative recombination rate. Consequently, the CsPbBr3 SCQDs film presents a high photoluminescence quantum yield (PLQY) of 85%. It enable...