To solve the problem of the global energy shortage and the pollution of the environment, in recent years, semiconductor photocatalytic technology that converts solar energy into chemical fuel has been widely studied. Regarding semiconductor-based photocatalysts, CdS has attracted extensive attention due to its relatively narrow bandgap for visible-light response and sufficiently negative potential of the conduction band edge for the reduction of protons. Studies have shown that CdS-based photocatalysts possess excellent photocatalytic performance in terms of solar-fuel generation and environmental purification. This critical review presents the recent advances and progress in the design and synthesis of various CdS and CdS-based photocatalysts. The basic physical and chemical properties of CdS and the related growth mechanism have been briefly summarized. Moreover, the applications of CdS-based photocatalysts have been discussed such as in photocatalytic hydrogen production, reduction of CO2 to hydrocarbon fuels and degradation of pollutants. Finally, a brief perspective on the challenges and future directions for the development of CdS and CdS-based photocatalysts are also presented.

CdS-Based photocatalysts

This article reports on the International Nanofluid Property Benchmark Exercise, or INPBE, in which the thermal conductivity of identical samples of colloidally stable dispersions of nanoparticles or “nanofluids,” was measured by over 30 organizations worldwide, using a variety of experimental approaches, including the transient hot wire method, steady-state methods, and optical methods. The nanofluids tested in the exercise were comprised of aqueous and nonaqueous basefluids, metal and metal oxide particles, near-spherical and elongated particles, at low and high particle concentrations. The data analysis reveals that the data from most organizations lie within a relatively narrow band (±10% or less) about the sample average with only few outliers. The thermal conductivity of the nanofluids was found to increase with particle concentration and aspect ratio, as expected from classical theory. There are (small) systematic differences in the absolute values of the nanofluid thermal conductivity among the various experimental approaches; however, such differences tend to disappear when the data are normalized to the measured thermal conductivity of the basefluid. The effective medium theory developed for dispersed particles by Maxwell in 1881 and recently generalized by Nan et al. [J. Appl. Phys. 81, 6692 (1997)], was found to be in good agreement with the experimental data, suggesting that no anomalous enhancement of thermal conductivity was achieved in the nanofluids tested in this exercise.

A Benchmark Study on the Thermal Conductivity of Nanofluids

Review on the criteria anticipated for the fabrication of highly efficient ZnO-based visible-light-driven photocatalysts

Photocatalytic degradation of organic pollutants using TiO2-based photocatalysts: A review

Wastewater treatment by means of advanced oxidation processes based on cavitation – A review

ANN ‐based modelling of peppermint flavour encapsulation process with ultrasound approach

Ultrasound-Assisted Synthesis and Its Effect on the Properties of CaCO3–Polymer Nanocomposites

Inorganic halloysite nanocontainers were employed for controlled delivery of plant growth regulator (PGR)–Gibberellic Acid. The cylindrical geometry of nanocontainer was found to be found to indicate 600 ± 200 nm length and 50 ± 10 nm outer diameter with inner lumen to be in the range of 12–15 nm. Attempts were made to encapsulate GA and obtain controlled release in aqueous buffer through nanocontainers capped with a copper stopper. Halloysite nanocontainers were characterized using TEM, EDX and TGA. In vitro release studies of GA in water were studied wherein the pH of the solution was maintained using phosphate buffer. Increase in amount of copper was found to be successful in retarding the amount of GA release. Complex between GA and copper ions was found to be responsible for the stopper formation. For tube stopper opening, addition of excessive amounts of ammonia solution was added. Parameters such as effect of temperature, pH and UV light were studied in detail. Encapsulation and stopper formation onto the nanocontainer was found to effective in achieving overall release control. Kinetic release model proposed by Peppas was analyzed for best fit.

Halloysite nanocontainers for controlled delivery of Gibberellic Acid

Bio-based graphitic carbon was synthesized in this work by one-step carbonization of bamboo waste at low temperature. This bio-based carbon was then functionalized in order to decorated it with Fe3 O4 nanoparticles. The functionalized biocarbon-Fe3 O4 (f-biocarbon-Fe3 O4 ) nanocomposite was synthesized using ultrasound-assisted coprecipitation method which was then confirmed by scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray diffractometry. Water-based nanofluid was prepared using the synthesized f-biocarbon-Fe3 O4 nanocomposite particles. Thermal conductivity of this nanofluid was analyzed at different concentrations and temperatures. A thermal conductivity enhancement of almost 80% was recorded at 35°C for nanofluid containing 0.1 vol.% of f-biocarbon-Fe3 O4 nanocomposite particles compared to water. Also, empirical model is developed for prediction of thermal conductivity as a function of concentration and temperature of bamboo waste-derived f-biocarbon-Fe3 O4 nanocomposite-based green nanofluid.

/pdf/synthesis-and-thermal-conductivity-of-functionalized-16qjvaal3c.pdf

Synthesis and thermal conductivity of functionalized biocarbon-Fe3O4 nanocomposite-based green nanofluid for heat transfer applications

Sonochemical preparation of hybrid polymer nanocomposite provides fine dispersion of the inorganic materials in the polymer matrix. Various literature reports show significant enhancement in the dispersion of nanofillers in the polymer matrix during sonochemical polymerization process, which can be attributed to the cavitational effects induced due to ultrasonic irradiations. Because of fine dispersion of these nanofillers in the polymer matrix, is shown significant enhancement in the various properties, for example, mechanical (crosscut adhesion), thermal, anticorrosion, and sensing properties. In this chapter, the study on the sonochemical preparation of hybrid polymer nanocomposite and their property profile will be reported. Finally, various case studies on the sonochemical preparation of hybrid polymer nanocomposites will also be reported.

Bharat A. Bhanvase

Papers

ANN ‐based modelling of peppermint flavour encapsulation process with ultrasound approach

Ultrasound-Assisted Synthesis and Its Effect on the Properties of CaCO3–Polymer Nanocomposites

Halloysite nanocontainers for controlled delivery of Gibberellic Acid

Synthesis and thermal conductivity of functionalized biocarbon-Fe3O4 nanocomposite-based green nanofluid for heat transfer applications

Sonochemical preparation of hybrid polymer nanocomposites: Properties and applications