Superior Performances of Electroless-Deposited Ni–P Films Decorated with an Ultralow Content of Pt for Water-Splitting Reactions

The design of highly efficient and low-cost electrocatalysts for the hydrogen evolution reaction (HER) is a critical endeavor, especially in alkaline electrolytes. Herein, we report the development of ultralow-amount Pt-decorated Ni–P catalysts on nickel foam substrates (Pt/Ni–P/NF) via a facile electroless deposition of Ni–P alloys subsequently decorated with a very small amount of Pt nanoparticles through a dip-coating procedure. Benefiting from the 3D porous backbone of the NF substrate and from the synergistic effect between Ni–P and Pt, the present Pt/Ni–P/NF catalyst demonstrates superior HER activity compared to most of the state-of-the-art Pt-based electrocatalysts, with a very low overpotential (22 mV at 10 mA cm–2) and Tafel slope (30 mV dec–1) and a high turnover frequency (1.78 s–1) at η = 50 mV. Furthermore, a full alkaline electrolyzer is constructed using Pt/Ni–P/NF as the cathode and undecorated Ni–P as the anode, which can drive overall water splitting with a low potential of 1.64 V at 10 mA cm–2. This work engenders novel possibilities toward the design of advanced ultralow-content Pt electrocatalysts fulfilling both excellent HER performance and low-cost requirements

Band Engineering versus Catalysis: Enhancing the Self-Propulsion of Light-Powered MXene-Derived Metal–TiO₂ Micromotors To Degrade Polymer Chains

Light-powered micro- and nanomotors based on photocatalytic semiconductors convert light into mechanical energy, allowing self-propulsion and various functions. Despite recent progress, the ongoing quest to enhance their speed remains crucial, as it holds the potential for further accelerating mass transfer-limited chemical reactions and physical processes. This study focuses on multilayered MXene-derived metal–TiO2 micromotors with different metal materials to investigate the impact of electronic properties of the metal–semiconductor junction, such as energy band bending and built-in electric field, on self-propulsion. By asymmetrically depositing Au or Ag layers on thermally annealed Ti3C2Tx MXene microparticles using sputtering, Janus structures are formed with Schottky junctions at the metal–semiconductor interface. Under UV light irradiation, Au–TiO2 micromotors show higher self-propulsion velocities due to the stronger built-in electric field, enabling efficient photogenerated charge carrier separation within the semiconductor and higher hole accumulation beneath the Au layer. On the contrary, in 0.1 wt % H2O2, Ag–TiO2 micromotors reach higher velocities both in the presence and absence of UV light irradiation, owing to the superior catalytic properties of Ag in H2O2 decomposition. Due to the widespread use of plastics and polymers, and the consequent occurrence of nano/microplastics and polymeric waste in water, Au–TiO2 micromotors were applied in water remediation to break down polyethylene glycol (PEG) chains, which were used as a model for polymeric pollutants in water. These findings reveal the interplay between electronic properties and catalytic activity in metal–semiconductor junctions, offering insights into the future design of powerful light-driven micro- and nanomotors with promising implications for water treatment and photocatalysis applications

Band Engineering versus Catalysis: Enhancing the Self-Propulsion of Light-Powered MXene-Derived Metal–TiO₂ Micromotors To Degrade Polymer Chains

Light-powered micro- and nanomotors based on photocatalytic semiconductors convert light into mechanical energy, allowing self-propulsion and various functions. Despite recent progress, the ongoing quest to enhance their speed remains crucial, as it holds the potential for further accelerating mass transfer-limited chemical reactions and physical processes. This study focuses on multilayered MXene-derived metal–TiO2 micromotors with different metal materials to investigate the impact of electronic properties of the metal–semiconductor junction, such as energy band bending and built-in electric field, on self-propulsion. By asymmetrically depositing Au or Ag layers on thermally annealed Ti3C2Tx MXene microparticles using sputtering, Janus structures are formed with Schottky junctions at the metal–semiconductor interface. Under UV light irradiation, Au–TiO2 micromotors show higher self-propulsion velocities due to the stronger built-in electric field, enabling efficient photogenerated charge carrier separation within the semiconductor and higher hole accumulation beneath the Au layer. On the contrary, in 0.1 wt % H2O2, Ag–TiO2 micromotors reach higher velocities both in the presence and absence of UV light irradiation, owing to the superior catalytic properties of Ag in H2O2 decomposition. Due to the widespread use of plastics and polymers, and the consequent occurrence of nano/microplastics and polymeric waste in water, Au–TiO2 micromotors were applied in water remediation to break down polyethylene glycol (PEG) chains, which were used as a model for polymeric pollutants in water. These findings reveal the interplay between electronic properties and catalytic activity in metal–semiconductor junctions, offering insights into the future design of powerful light-driven micro- and nanomotors with promising implications for water treatment and photocatalysis applications

Band Engineering versus Catalysis: Enhancing the Self-Propulsion of Light-Powered MXene-Derived Metal–TiO₂ Micromotors To Degrade Polymer Chains

Light-powered micro- and nanomotors based on photocatalytic semiconductors convert light into mechanical energy, allowing self-propulsion and various functions. Despite recent progress, the ongoing quest to enhance their speed remains crucial, as it holds the potential for further accelerating mass transfer-limited chemical reactions and physical processes. This study focuses on multilayered MXene-derived metal–TiO2 micromotors with different metal materials to investigate the impact of electronic properties of the metal–semiconductor junction, such as energy band bending and built-in electric field, on self-propulsion. By asymmetrically depositing Au or Ag layers on thermally annealed Ti3C2Tx MXene microparticles using sputtering, Janus structures are formed with Schottky junctions at the metal–semiconductor interface. Under UV light irradiation, Au–TiO2 micromotors show higher self-propulsion velocities due to the stronger built-in electric field, enabling efficient photogenerated charge carrier separation within the semiconductor and higher hole accumulation beneath the Au layer. On the contrary, in 0.1 wt % H2O2, Ag–TiO2 micromotors reach higher velocities both in the presence and absence of UV light irradiation, owing to the superior catalytic properties of Ag in H2O2 decomposition. Due to the widespread use of plastics and polymers, and the consequent occurrence of nano/microplastics and polymeric waste in water, Au–TiO2 micromotors were applied in water remediation to break down polyethylene glycol (PEG) chains, which were used as a model for polymeric pollutants in water. These findings reveal the interplay between electronic properties and catalytic activity in metal–semiconductor junctions, offering insights into the future design of powerful light-driven micro- and nanomotors with promising implications for water treatment and photocatalysis applications

Band Engineering versus Catalysis: Enhancing the Self-Propulsion of Light-Powered MXene-Derived Metal–TiO₂ Micromotors To Degrade Polymer Chains

Light-powered micro- and nanomotors based on photocatalytic semiconductors convert light into mechanical energy, allowing self-propulsion and various functions. Despite recent progress, the ongoing quest to enhance their speed remains crucial, as it holds the potential for further accelerating mass transfer-limited chemical reactions and physical processes. This study focuses on multilayered MXene-derived metal–TiO2 micromotors with different metal materials to investigate the impact of electronic properties of the metal–semiconductor junction, such as energy band bending and built-in electric field, on self-propulsion. By asymmetrically depositing Au or Ag layers on thermally annealed Ti3C2Tx MXene microparticles using sputtering, Janus structures are formed with Schottky junctions at the metal–semiconductor interface. Under UV light irradiation, Au–TiO2 micromotors show higher self-propulsion velocities due to the stronger built-in electric field, enabling efficient photogenerated charge carrier separation within the semiconductor and higher hole accumulation beneath the Au layer. On the contrary, in 0.1 wt % H2O2, Ag–TiO2 micromotors reach higher velocities both in the presence and absence of UV light irradiation, owing to the superior catalytic properties of Ag in H2O2 decomposition. Due to the widespread use of plastics and polymers, and the consequent occurrence of nano/microplastics and polymeric waste in water, Au–TiO2 micromotors were applied in water remediation to break down polyethylene glycol (PEG) chains, which were used as a model for polymeric pollutants in water. These findings reveal the interplay between electronic properties and catalytic activity in metal–semiconductor junctions, offering insights into the future design of powerful light-driven micro- and nanomotors with promising implications for water treatment and photocatalysis applications

Band Engineering versus Catalysis: Enhancing the Self-Propulsion of Light-Powered MXene-Derived Metal–TiO₂ Micromotors To Degrade Polymer Chains

Light-powered micro- and nanomotors based on photocatalytic semiconductors convert light into mechanical energy, allowing self-propulsion and various functions. Despite recent progress, the ongoing quest to enhance their speed remains crucial, as it holds the potential for further accelerating mass transfer-limited chemical reactions and physical processes. This study focuses on multilayered MXene-derived metal–TiO2 micromotors with different metal materials to investigate the impact of electronic properties of the metal–semiconductor junction, such as energy band bending and built-in electric field, on self-propulsion. By asymmetrically depositing Au or Ag layers on thermally annealed Ti3C2Tx MXene microparticles using sputtering, Janus structures are formed with Schottky junctions at the metal–semiconductor interface. Under UV light irradiation, Au–TiO2 micromotors show higher self-propulsion velocities due to the stronger built-in electric field, enabling efficient photogenerated charge carrier separation within the semiconductor and higher hole accumulation beneath the Au layer. On the contrary, in 0.1 wt % H2O2, Ag–TiO2 micromotors reach higher velocities both in the presence and absence of UV light irradiation, owing to the superior catalytic properties of Ag in H2O2 decomposition. Due to the widespread use of plastics and polymers, and the consequent occurrence of nano/microplastics and polymeric waste in water, Au–TiO2 micromotors were applied in water remediation to break down polyethylene glycol (PEG) chains, which were used as a model for polymeric pollutants in water. These findings reveal the interplay between electronic properties and catalytic activity in metal–semiconductor junctions, offering insights into the future design of powerful light-driven micro- and nanomotors with promising implications for water treatment and photocatalysis applications

Low-Cost, High-Yield Zinc Oxide-Based Nanostars for Alkaline Overall Water Splitting

The investigation of high-efficiency and sustainable electrocatalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in alkaline media is critical for renewable energy technologies. Here, we report a low-cost and high-yield method to obtain ZnOHF-ZnO-based 2D nanostars (NSs) by means of chemical bath deposition (CBD). The obtained NSs, cast onto graphene paper substrates, were used as active materials for the development of a full water splitting cell. For the HER, NSs were decorated with an ultralow amount of Pt nanoparticles (11.2 μg cm–2), demonstrating an overpotential of 181 mV at a current density of 10 mA cm–2. The intrinsic activity of Pt was optimized, thanks to the ZnO supporting nanostructures, as outlined by the mass activity of Pt (0.9 mA mgPt–1) and its turnover frequency (0.27 s–1 for a Pt loading of 11.2 μg cm–2). For the OER, bare NSs showed a remarkable result of 355 mV at 10 mA cm–2 in alkaline media. Pt-decorated and bare NSs were used as the cathode and anode, respectively, for alkaline electrochemical water splitting, assessing a stable overpotential of 1.7 V at a current density of 10 mA cm–2. The reported data pave the way toward large-scale production of low-cost electrocatalysts for green hydrogen production

Human vitreous concentrations of citicoline following topical application of citicoline 2% ophthalmic solution - Fig 2

(A-B). Vitreous concentration of citicoline and metabolites. Citicoline and metabolites presence in human vitreous from control eyes (n = 5) and citicoline 2% treated eyes (n = 21). Samples were subjected to specific HPLC evaluations, after a protein extraction. (A) Citicoline, choline, cytidine and uridine values (μg/mL) in vitreous from control and citicoline 2% treated eyes. (B) Comparison between phakic (n = 13) and pseudophakic (n = 8) eyes in citicoline 2% treated eyes. Mann-Whitney U test T was used for statistical analysis.</p

Demographic and clinical characteristics of patients treated with citicoline 2% ophthalmic solution.

Demographic and clinical characteristics of patients treated with citicoline 2% ophthalmic solution.</p

Human vitreous concentrations of citicoline following topical application of citicoline 2% ophthalmic solution - Fig 1

(A-E). Representative chromatogram of a mixture of citicoline and metabolites. Representative chromatogram of a mixture of citicoline and metabolites. (A) HPLC chromatogram obtained for standard mixture containing citicoline, choline, cytidine and uridine at concentration of 50 ng/mL. The retention times are reported close to each peak, as indicative of specificity of analysis. Peak purity data (areas) were used to produce a standard curve as shown in panels (B) for citicoline, (C) for choline, (D) for cytidine and (E) for uridine. The linearity curve for each analytics was confirmed by the R2 value of the polynomial curve (3rd grade), as shown in each panel. Chromatogram parameters were as described in the materials and methods paragraph. In preliminary tests, a run time of 25 min was performed to assure the absence of other contaminants and to assess the background noise, and thereafter reduced to 10 min.</p