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In this study silver nanoparticles were prepared by chemical reduction method using silver nitrate as metal precursor, starch as protecting agent, and sodium borohydride (NaBH 4 ) as a reducing agent. Formation of silver nanoparticles was monitored using UV−vis absorption spectroscopy and dynamic light scattering (DLS). They were supported on silica by dispersing silica powder in the suspension of destabilized silver nanoparticles. Samples containing different proportions of silver were thus prepared. This method is at variance from the conventionally employed method, i.e., impregnation of silver salt from its solution on support. Ag/SiO 2 samples were characterized by UV−vis absorption spectroscopy, transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), inductive coupled plasma optical emission spectroscopy (ICP-OES), and N 2 adsorption−desorption. Superior catalytic performance of the catalyst prepared by the present method could be observed in a test reaction of ethylbenzene oxidation affording high selectivity to acetophenone as compared to the catalyst prepared by the conventional reported methods. The 5 wt % Ag/SiO 2 catalyst was found not much susceptible to sintering as could be inferred from the comparable performance of the regenerated and fresh catalysts.

In the presence of molecular oxygen, a {001}-faceted nanocrystalline anatase TiO catalyst enabled the selective oxidation of nonactivated aliphatic alcohols to the corresponding aldehydes or ketones under visible light. The reaction shows excellent conversion and selectivity towards the formation of the carbonyl products without over-oxidation to the corresponding carboxylic acids. The exceptional reactivity of the catalyst is possibly due to the absorption of visible light originating from a stronger interaction of alcohol with the {001} facet, which facilitates the modification of the band structure of TiO , thus facilitating the photogenerated hole transfer and subsequent oxidation processes. The experimental results have also been corroborated by first-principles quantum chemical DFT calculations.

Exploring the generation of efficient and long‐lasting bifunctional electrocatalysts obtained from low‐cost transition metal oxides is crucial to the optimal production of hydrogen and oxygen by electrocatalytic water splitting. This study aims to demonstrate the applicability of layered TiO2 nanosheets as support for designing electrocatalysts. We have demonstrated the performance by decorating the TiO2 support with NiCo2O4 nanoparticles (NiCo2O4/TiO2) as catalysts for electrocatalytic overall water splitting. Moreover, the corrosion effect of usually used carbon‐based supporting materials can decrease the working efficiency and, thus, the overall performance of the catalysts. In this aspect, TiO2 can be a better alternative to carbon‐based systems. Layered TiO2 was synthesized at room temperature, and a simple heat treatment protocol was employed for the large‐scale synthesis of NiCo2O4/TiO2. TiO2 facilitated the formation of smaller NiCo2O4 nanoparticles, also improving the dispersion. This bifunctional electrocatalyst exhibits high OER and HER performance with a low overpotential of 309 mV and 185 mV respectively, at a current density of 10 mA cm−2. TiO2 supported catalyst also exhibits other advantages like remarkable durability in the alkaline medium along with high turnover frequency (TOF) values. This inexpensive catalyst can deliver a current density of 10 mA cm−2 at only 1.64 V with a steady performance for more than 12 h for overall water splitting. Thus, this homemade system provides a proficient and low‐cost alternative to the more expensive systems such as RuO2, IrO2 or Pt for the electrochemical water splitting applications.