arXiv subjects

Xinjuan Li

Publications and source records attributed to Xinjuan Li.

3 recordsLinked to original sources

arXiv2026

Rapid Atmospheric Vapor Deposition of H:In2O3 Transparent Conducting Oxide Thin Films

Transparent conducting oxides (TCOs) are essential for the optoelectronics industry, but there is a critical gap in cost-effective methods to rapidly deposit low sheet resistance, high transmittance films without damaging delicate materials, including emerging soft semiconductors like metal-halide perovskites. In this work, atmospheric pressure chemical vapor deposition (AP-CVD) is used to synthesise H:In2O3 films with 7.20+/-0.01 Ohm/sq sheet resistance (0.50+/-0.06 mOhm.cm resistivity) and transmittance up to 89% in the near-infrared (NIR), surpassing commercial sputter-deposited indium tin oxide. The growth rate is 40x higher than atomic layer deposition (ALD), and the AP-CVD films are fully processed under atmospheric conditions at only 140 C. Comparison of secondary ion mass spectrometry and time-of-flight elastic recoil detection analysis with changes in carrier concentration indicate that H dopants are introduced from the water oxidant. There is an increase in mobility form 40+/-10 cm2/Vs to 160+/-30 cm2/Vs when changing from O2 to H2O as the oxidant, which is attributed to H dopants passivating oxygen vacancies that act as carrier scattering centers. This work establishes AP-CVD as a promising method for manufacturing high figure-of-merit TCOs in a rapid, scalable and cost-effective manner, using mild growth conditions compatible with thermally-sensitive materials.

cond-mat.mtrl-sci↗

arXiv2026

Boosting high-current alkaline water electrolysis and carbon dioxide reduction with novel CuNiFe-based anodes

The transition to a green hydrogen economy demands robust, scalable, and sustainable anodes for alkaline water electrolysis operating at industrial current densities (>1 A/cm2). However, achieving high activity and long-term stability under such conditions remains a formidable challenge with conventional catalysts. Here, we report a novel trimetallic CuNiFe anode fabricated through a rapid, single-step electrodeposition process at room temperature without organic additives. The catalyst exhibits an exceptionally low overpotential of <270 mV at 100 mA cm(-2) and operates stably for over 500 hours at 1 A cm(-2) in 30 wt% KOH. In a practical anion exchange membrane water electrolyzer (AEM-WE), the CuNiFe anode enables a current density of 2.5 A cm(-2) at only 2.5 V, with a voltage efficiency of 66.8%. Beyond water splitting, this anode also significantly enhances CO2 electrolysis, tripling the CO2 reduction current density and steering selectivity toward valuable multi-carbon products when paired with commercial copper cathodes. A cradle-to-gate life cycle assessment confirms that the CuNiFe anode reduces the carbon footprint by an order of magnitude and decreases environmental impacts by 40-60% across multiple categories compared to benchmark IrRuO2. Our work establishes a scalable, high-performance, and environmentally benign anode technology, paving the way for cost-effective electrochemical production of green hydrogen and carbon-neutral chemicals.

cond-mat.mtrl-sci↗

arXiv2024

Efficient short-wave infrared upconversion by self-sensitized holmium-doped nanoparticles

Photon upconversion, combining several low-energy photons to generate one high-energy photon is of wide interest for biomedical, catalytic and photonic applications. Lanthanide-doped nanoparticles (LnNP) are a unique type of upconversion nanoconverter, which can realize ultralarge anti-Stokes shift (>1000 nm) and high photostability, without photo-bleaching and photo-blinking. The excitation wavelength of LnNPs has been limited to the second near-infrared window (1000-1700 nm), mainly sensitized by erbium ions with absorption centered around 1.5 $μ$m. Here, we demonstrate novel self-sensitized holmium (Ho)-doped nanoconverters to further expand the sensitization range to the short-wave infrared at 2 $μ$m and achieve efficient upconversion to 640 nm. We show that this upconversion is a 4-photon conversion process with an underlying energy transfer upconversion mechanism. Via careful control of dopant concentration and shelling we achieve a relative upconversion-to-downconversion efficiency up to 15.2%, more than half the theoretical maximum. The placement of the Ho doped LnNPs into a plasmonic nanocavity device enables large gains in emission intensity (up to 32-fold), due to the dramatic shortening of the emission lifetime of Ho from 29 $μ$s to <1 ns, indicating a high Purcell-enhancement factor of 3x10$^4$. These results open new possibilities at the frontier of short-wave infrared upconversion and the nanoplasmonic enhancement of LnNP emission, with potential applications in detection, theranostics, photonics and optoelectronics.

physics.optics↗