have demonstrated that Pd 3Au 1 nanoparticles supported on carbon nanotubes could reduce the THQ dehydrogenation time by around 50 % (12 h) at a slightly higher temperature (140 ☌) and at a lower catalyst loading. have shown that the dendrimer-stabilized nanoparticles of palladium (Pd), platinum (Pt), and rhodium (Rh) supported on SBA-15 silica can drive the dehydrogenation of 1,2,3,4-tetrahydroquinoline (THQ) to completion in 23 h at 130 ☌. 7 Heterogeneous dehydrogenation catalysts that operate at temperatures higher than 120 ☌ and contain precious metal supported nanoparticles have been developed to address this issue at yields exceeding 95 %. 6 Moreover, catalyst stability and recycling issues can further complicate the design of these processes. 5 N-substituted heterocycles have lower dehydrogenation energy barrier when compared to cycloalkanes, and thus provide a low-energy opportunity for H 2 release. 4 However, the energy consumption and cost of generation and storage of H 2, including the water electrolysis (>$5 kg −1), or the high temperature water-gas shift (WGS) reaction (>400 ☌) as well as the cost of the H 2 storage/release process (>$1 kg −1) hamper the overall feasibility of the process. Over the past decade, several catalytic processes have been developed for H 2 generation and storge. 2 The existing fuel storage and distribution infrastructure are designed to handle liquid fuels, and thus storing H 2 in the form of liquid organic hydrogen carrier (LOHC) allows for facile retrofitting of current global infrastructure for H 2 economy. Hydrogen (H 2) is a clean and high-density form of energy storage that can be directly used in internal combustion engines and fuel cells. However, the intermittent nature of these alternative energy sources necessitates the development of green and sustainable energy storage and transportation technologies to maintain constant power supply.

1 Renewable energy sources including solar, wind, and biomass are attractive alternatives to fossil fuels that will help reduce worldwide carbon emissions. Stringent regulations on carbon emissions are expected in the near future because of the accelerating negative environmental impacts of global warming. An example of using quinoline as a hydrogen acceptor to lower the energy of the hydrogen production step was demonstrated via the water-gas shift reaction. The tradeoff between the reactor pressure drop and its photocatalytic surface area was resolved by selective in-situ photodeposition of Rh in the photo flow reactor post-packing on the outer surface of the TiO 2 microparticles available to photon flux, thereby reducing the optimal Rh loading by 10 times compared to a batch reactor, while facilitating catalyst reuse and regeneration.

In response, a photo flow reactor packed with rhodium (Rh)/titania (TiO 2) photocatalyst was reported for the continuous and selective acceptorless dehydrogenation of 1,2,3,4-tetrahydroquinoline to H 2 gas and quinoline under visible light irradiation at room temperature. Despite the potential of hydrogen (H 2) storage in liquid organic carriers to achieve carbon neutrality, the energy required for H 2 release and the cost of catalyst recycling have hindered its large-scale adoption.

Photoflow liquid for cleaning records