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Indium gallium nitride nanocubes were syntheized via a low-temperature chemical route. Energy-dispersive X-ray spectroscopy and X-ray diffraction analyses confirmed the successful fabrication of (In,Ga)N with various indium mole fractions. The bandgap of the material was tunded as a function of the indium content. The fabricated nanocubes showed a deep level photoluminescence emission at 734 nm as well as in the visible region at 435-520 nm. The Hall effect measurements showed the hole concentration to constantly increase from 6.2 × 10(16) to 2.3 × 10(18) cm(-3), while the hole mobility to decrease from 0.92 to 0.1 cm(2) /(V s) as the doping ratio increases from 0.005 to 0.025 cm(-3). The solar cell device made of nanocubes film containing 0.4 indium on flexible substrates showed a short-circuit current density of 12.47 mA/cm(2) and an open-circuit voltage (Voc) of 0.48 V with 54% fill factor. The relationship between Voc and indium content in the fabricated films was also investigated.

Acrylic acid, conventionally produced via propylene (non‐renewable fossil fuel route), is an industrially important chemical. The bio‐based feedstock process employing glycerol (a by‐product of biodiesel production) has attracted the attention of researchers due to its non‐polluting and renewable characteristics. Bi/multifunctional catalysts using a combination of zeolites, metal oxides, heteropoly acids, and phosphates have been mainly studied for the glycerol oxydehydration process. Brønsted acid sites favour acrolein generation over Lewis acid sites, whereas the redox sites convert the generated acrolein to acrylic acid. So far, the maximum acrylic acid yields of 60% and 59% have been reported on heteropoly acid and mixed metal oxide catalysts, respectively. Some DFT studies also revealed the deprotonation energy of acid sites and further helped in designing efficient catalysts. Despite these accomplishments, catalyst deactivation because of coking and stability remains a major problem. In this paper, various bi/multifunctional catalysts employed in glycerol oxydehydration to acrylic acid are critically reviewed. Different catalyst forms, preparation techniques, reaction kinetics, reaction mechanisms, deactivation, reactivation, process operating parameters, and sustainability are considered. In addition, the challenges associated with each catalyst type and strategies to overcome low yield, deactivation, and future directions are discussed.

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