With the increasing power requirements of integrated circuits, the demand for efficient cooling has followed suit. Silicone grease is commonly used due to its thermal stability and ability to fill in airgaps between the electronic components and radiators. Previous works attempted to increase the grease’s thermal conductivity by adding various additives such as boron nitride or functionalized carbon nanotubes. Functionalized graphene was chosen in this study due to its exceptional physical and chemical properties. Results show that the functionalization with several acid mixtures combined with ball milling resulted in a compound chemically equivalent to graphene and thoroughly dispersed in silicone grease. An optimal grease was produced, containing 1 wt.% Gr-COOH and possessing a thermal conductivity of 6.534 W/mK. The resulting grease’s performance in thermal dissipation and approximated lifespan improvements was compared to a commercially available silicone grease using a 200W LED. Results indicated a 4.5℃ decrease in saturation temperature of LED chip along with a 257% increase in thermal conductivity.

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The hydrothermal carbonization (HTC) of avocado peel was investigated by varying the reaction temperature, reaction time, and catalyst/feedstock ratio. After the HTC process, there was a drastic change in both the structure and chemical composition of the hydrochar compared to the feedstock. This modification aids hydrochar’s improved fuel characteristics, as seen by a drop in the H/C and O/C ratios, as well as an increase in fixed carbon content. The higher heating value (HHV) increased in the feedstock to a maximum value of 27.15 MJ·kg−1, corresponding to hydrochar, which is obtained at an optimized condition. Notably, the HHV and carbon content of the noncatalytic sample are only higher than those of the feedstock but lower than those of the samples surveyed. The combustion behavior and thermal characteristics of hydrochars show that the HTC of the avocado peel in the presence of FeCl3 catalyst introduces a possible direction of application in converting agro-industrial by-products into fuel.

A composite of TiO2 quantum dots (TiO2QDs) and TiO2 nanoparticles (TiO2NPs) was successfully deposited on glass beads (GBs), with a very low content of TiO2 (<0.3 wt%), by a rapid, simple, inexpensive, and scalable synthesis method. The TiO2QDs-TiO2NPs/GBs catalyst possesses an extremely high photocatalytic performance under simulated solar irradiation, with the complete degradation of the aqueous solutions of methylene blue in 60 minutes of photodegradation. There were no changes in the catalytic activity after six times of recycling. The superior performance of the catalyst should be attributed to the role of the synergistic effect between TiO2NPs and TiO2QDs to prevent the accumulation of TiO2 nanoparticles during the oxidation reaction, to improve the absorption in the visible region, to enhance the immigration of photogenerated electrons and holes in interfaces of two materials in the TiO2QDs-TiO2NPs composite, which leads to a reduced charge recombination rate, and to generate midgap states and suppress the recombination of electron-hole pairs.