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This work highlights a strategy for the one-step synthesis of FeAu nanoparticles by the pulsed laser ablation of alloy targets in the presence of different solvents. This method allows particle generation without the use of additional chemicals; hence, solvent-metal interactions could be studied without cross effects from organic surface ligands. A detailed analysis of generated particles via transmission electron microscopy in combination with EDX elemental mapping could conclusively verify that the nature of the used solvent governs the internal phase structure of the formed nanoparticles. In the presence of acetone or methyl methacrylate, a gold shell covering a non-oxidized iron core was formed, whereas in aqueous media, an Au core with an Fe₃O₄ shell was generated. This core-shell morphology was the predominant species found in >90% of the examined nanoparticles. These findings indicate that fundamental chemical interactions between the nanoparticle surface and the solvent significantly contribute to phase segregation and elemental distribution in FeAu nanoparticles. A consecutive analysis of resulting Fe@Au core-shell nanoparticles revealed outstanding oxidation resistance and fair magnetic and optical properties. In particular, the combination of these features with high stability magnetism and plasmonics may create new opportunities for this hybrid material in imaging applications.

Nanostructured composites of inorganic and organic materials are attracting extensive interest for electronic and optoelectronic device applications. Here we report a novel method for the fabrication and patterning of metal selenide nanoparticles in organic semiconductor films that is compatible with solution processable large area device manufacturing. Our approach is based upon the controlled in situ decomposition of a cadmium selenide precursor complex in a film of the electron transporting material 1,3,5-tris(N-phenyl-benzimidazol-2-yl)-benzene (TPBI) by thermal and optical methods. In particular, we show that the photoluminescence quantum yield (PLQY) of the thermally converted CdSe quantum dots (QDs) in the TPBI film is up to 15%. We also show that laser illumination can form the QDs from the precursor. This is an important result as it enables direct laser patterning (DLP) of the QDs. DLP was performed on these nanocomposites using a picosecond laser. Confocal microscopy shows the formation of emissive QDs after laser irradiation. The optical and structural properties of the QDs were also analysed by means of UV-Vis, PL spectroscopy and transmission electron microscopy (TEM). The results show that the QDs are well distributed across the film and their emission can be tuned over a wide range by varying the temperature or irradiated laser power on the blend films. Our findings provide a route to the low cost patterning of hybrid electroluminescent devices.

The picosecond laser irradiation of diamond-like carbon (DLC) film on the silicon wasinvestigated. The DLC films were irradiated by Nd:YVO₄ laser with the infrared (1064 nm, fluency 1.02 J/cm²) and ultraviolet (355 nm, fluency 0.79 J/cm²) wavelengths with 1, 10, and 100 pulse numbers per spot. The energy dispersive X-ray spectroscopy and microRaman spectroscopy measurements indicated that the full ablation area of the DLC was narrower than laser beam radius of the 1064 nm wavelength with 10 and 100 pulses. The increase of the oxygen concentration was obtained near the ablation areas after irradiation with the first harmonic. The microRaman and SEM measurements demonstrated that the DLC film was fully ablated in the laser spot when the third harmonic was used. The formation of silicon carbide (SiC) in the center of the irradiated spot was found after 100 pulses.

Hybrid particles are of great significance in terms of their adjustable optical, electronic, magnetic, thermal and mechanical properties. As a novel technique, laser ablation in liquids (LAL) is famous for its precursor-free, “clean” synthesis of hybrid particles with various materials. Till now, almost all the LAL-generated particles originate from the nucleation-growth mechanism. Seed-growth of particles similar to chemical methods seems difficult to be achieved by LAL. Here, we not only present novel patch-joint football-like AgGe microspheres with a diameter in the range of 1 ~ 7 μm achievable by laser ablation in distilled water but also find direct evidences of their layered seed growth mechanism. Many critical factors contribute to the formation of AgGe microspheres: fast laser-generated plasma process provide an excellent condition for generating large amount of Ge and Ag ions/atoms, their initial nucleation and galvanic replacement reaction, while cavitation bubble confinement plays an important role for the increase of AgGe nuclei and subsequent layered growth in water after bubble collapse. Driven by work function difference, Ge acts as nucleation agent for silver during alloy formation. This new seed-growth mechanism for LAL technique opens new opportunities to develop a large variety of novel hybrid materials with controllable properties.

Perovskite solar cells with submicrometre-thick CH₃NH₃PbI₃ or CH₃NH₃PbI_3–xCl_x active layers show a power conversion efficiency as high as 15%. However, compared to the best-performing device, the average efficiency was as low as 12%, with a large standard deviation (s.d.). Here, we report perovskite solar cells with an average efficiency exceeding 16% and best efficiency of 17%. This was enabled by the growth of CH₃NH₃PbI₃ cuboids with a controlled size via a two-step spin-coating procedure. Spin-coating of a solution of CH₃NH₃I with different concentrations follows the spin-coating of PbI₂, and the cuboid size of CH₃NH₃PbI₃ is found to strongly depend on the concentration of CH₃NH₃I. Light-harvesting efficiency and charge-carrier extraction are significantly affected by the cuboid size. Under simulated one-sun illumination, average efficiencies of 16.4% (s.d. ± 0.35), 16.3% (s.d. ± 0.44) and 13.5% (s.d. ± 0.34) are obtained from solutions of CH₃NH₃I with concentrations of 0.038 M, 0.050 M and 0.063 M, respectively. By controlling the size of the cuboids of CH₃NH₃PbI₃ during their growth, we achieved the best efficiency of 17.01% with a photocurrent density of 21.64 mA cm^–2, open-circuit photovoltage of 1.056 V and fill factor of 0.741.

Chemoradiation-resistant cancers limit treatment efficacy and safety. We show here the cancer cell–specific, on-demand intracellular amplification of chemotherapy and chemoradiation therapy via gold nanoparticle– and laser pulse–induced mechanical intracellular impact. Cancer aggressiveness promotes the clustering of drug nanocarriers and gold nanoparticles in cancer cells. This cluster, upon exposure to a laser pulse, generates a plasmonic nanobubble, the mechanical explosion that destroys the host cancer cell or ejects the drug into its cytoplasm by disrupting the liposome and endosome. The same cluster locally amplifies external X-rays. Intracellular synergy of the mechanical impact of plasmonic nanobubble, ejected drug and amplified X-rays improves the efficacy of standard chemoradiation in resistant and aggressive head and neck cancer by 100-fold in vitro and 17-fold in vivo, reduces the effective entry doses of drugs and X-rays to 2–6% of their clinical doses and efficiently spares normal cells. The developed quadrapeutics technology combines four clinically validated components and transforms a standard macrotherapy into an intracellular on-demand theranostic microtreatment with radically amplified therapeutic efficacy and specificity.