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In the present review, we would like to draw the reader’s attention to the polymer-based hybrid materials used in photocatalytic processes for efficient degradation of organic pollutants in water. These inorganic–organic materials exhibit unique physicochemical properties due to the synergistic effect originating from the combination of individual elements, i.e., photosensitive metal oxides and polymeric supports. The possibility of merging the structural elements of hybrid materials allows for improving photocatalytic performance through (1) an increase in the light-harvesting ability; (2) a reduction in charge carrier recombination; and (3) prolongation of the photoelectron lifetime. Additionally, the great majority of polymer materials exhibit a high level of resistance against ultraviolet irradiation and improved corrosion resistance. Taking into account that the chemical and environmental stability of the hybrid catalyst depends, to a great extent, on the functional support, we highlight benefits and drawbacks of natural and synthetic polymer-based photocatalytic materials and pay special attention to the fact that the accessibility of synthetic polymeric materials derived from petroleum may be impeded due to decreasing amounts of crude oil. Thus, it is necessary to look for cheap and easily available raw materials like natural polymers that come from, for instance, lignocellulosic wastes or crustacean residues to meet the demand of the “plastic” market. [ABSTRACT FROM AUTHOR]

TiO2 (anatase phase) has excellent photocatalytic performance and different methods have been reported to overcome its main limitation of high band gap energy. In this work, TiO2-magnetically-separable nanocomposites (MAGSNC) photocatalysts with different TiO2 loading were synthesized using a simple one-pot mechanochemical method. Photocatalysts were characterized by a number of techniques and their photocatalytic activity was tested in the selective oxidation of benzyl alcohol to benzaldehyde. Extension of light absorption into the visible region was achieved upon titania incorporation. Results indicated that the photocatalytic activity increased with TiO2 loading on the catalysts, with moderate conversion (20%) at high benzaldehyde selectivity (84%) achieved for 5% TiO2-MAGSNC. These findings pointed out a potential strategy for the valorization of lignocellulosic-based biomass under visible light irradiation using designer photocatalytic nanomaterials. [ABSTRACT FROM AUTHOR]

A simple, low-temperature synthesis approach is reported for planting CdS-sensitized 1D ZnO nanorod arrays on the 2D graphene (GR) sheet to obtain the ternary hierarchical nanostructures, during which graphene oxide (GO) as the precursor of GR acts as a flexible substrate for the formation of ZnO nanorod arrays. The hierarchical CdS-1D ZnO-2D GR hybrids can serve as an efficient visible-light-driven photocatalyst for selective organic transformations. The fast electron transport of 1D ZnO nanorods, the well-known electronic conductivity of 2D GR, the intense visible-light absorption of CdS, the unique hierarchical structure, and the matched energy levels of CdS, ZnO and GR efficiently boost the photogenerated charge carriers separation and transfer across the interfacial domain of hierarchical CdS-1D ZnO-2D GR hybrids under visible light irradiation via three-level electron transfer process. Furthermore, the superior reusability of ternary hybrids is achieved by controlling the reaction parameters, i.e., using visible light irradiation and holes scavenger to prevent ZnO and CdS from photocorrosion. This work demonstrates a facile way of fabricating hierarchical CdS-1D ZnO-2D GR hybrids in a controlled manner and highlights a promising scope of adopting integrative photosensitization and co-catalyst strategy to design more efficient semiconductor-based composite photocatalysts toward solar energy capture and conversion. [ABSTRACT FROM AUTHOR]

The use of renewable local raw materials to produce fuels is an important step toward optimal environmentally friendly energy consumption. In addition, the use of these sources together with fossil fuels paves the way to an easier transition from fossil to renewable fuels. The use of simple organic acids as hydrogen donors is another alternative way to produce fuel. The present work reports the use of oxalic acid as a hydrogen donor for the catalytic hydrodesulfurization of atmospheric gas oil and the deoxygenation of rapeseed oil at 350 °C. For this process, one commercial NiW/SiO2–Al2O3 solid and two NiW/modified phonolite catalysts were used, namely Ni (5%) W (10%)/phonolite treated with HCl, and Ni (5%) W (10%)/phonolite treated with oxalic acid. The fresh phonolite catalysts were characterized by Hg porosimetry and N2 physisorption, ammonia temperature programmed desorption (NH3-TPD), X-ray diffraction (XRD), and X-ray fluorescence (XRF). The sulfided metal phonolite catalysts were characterized by XRD and XRF. Hydrodesulfurization led to a decrease in sulfur content from 1 to 0.5 wt% for the phonolite catalysts and to 0.8 wt% when the commercial catalyst was used. Deoxygenation led to the production of 15 and 65 wt% paraffin for phonolite and commercial solids, respectively. The results demonstrate the potential of using oxalic acid as a hydrogen donor in hydrotreating reactions. [ABSTRACT FROM AUTHOR]

A novel P‑doped mesoporous carbon (PMC) was prepared from sucrose, a natural source, using a hard template based on silica nanoparticles. The new PMC was characterized by SEM, TEM, XRD, N 2 physisorption, Raman, XPS, and FT-IR. The analysis confirmed the tridimensional structure of PMC, which showed a high surface area of 830 m2.g−1 and a pore volume of 1.4 cm3.g−1. XPS analysis determined the phosphorus content of 4.1 %, mainly due to the functional groups of C 3 -P O and C−P(O)(OH) 2 /C 2 −P(O)(OH). The new material was used to remove the drug propranolol (PRO) from water. PMC could remove PRO in 10 min, achieving a high removal capacity of 287 mg.g−1, corresponding to 99 % of removal efficiency. The kinetic and equilibrium data were best described by pseudo-second order kinetic and BET isothermal models, suggesting multilayer adsorption where the first layer of PRO molecules strongly binds to the PMC surface, and subsequent layers are formed over the first one. The proposed mechanism of PRO adsorption is based on the chemisorption in C−P(O)(OH) 2 /C 2 −P(O)(OH) acidic groups of PMC, physisorption through hydrogen-bonding, electrostatic and π − π interactions. PMC has proven to be a promising adsorbent for the uptake of propranolol from water. [Display omitted] • P-doped mesoporous carbon was synthesized from a natural source of sucrose. • The novel material has high surface area, mesoporosity, and diverse functional groups. • The adsorption of propranolol is fast, efficient, and occurs by the formation of multilayers. • Both physio/chemisorption are responsible for the uptake of propranolol. • C−P(O)(OH) 2 /C 2 −P(O)(OH) groups play a critical role in the removal of propranolol. [ABSTRACT FROM AUTHOR]

The article in Advanced Energy Materials discusses the development of air-stable EDABiI5/MA3Bi2I9 perovskite heterojunctions for photocatalytic hydrogen evolution. Researchers found that these heterostructures can enhance charge-carrier transport and electron transfer, improving solar-to-fuel conversion efficiency. The study provides valuable insights into the design of next-generation semiconductors for solar-to-fuel technology. [Extracted from the article]

[Display omitted] • Atomically dispersed Cu on TiO2 nanoparticles synthesized by the wet impregnation method; • 100% Selectivity to hydrogen in the methanol photoreforming has been achieved; • Cu2+ Oxidation state bypassed to prevent CO 2 generation; • Cu+→Cu0 → Cu+ Redox cycle identified under the reaction conditions; • An apparent quantum efficiency of 10% at λ = 365 nm and the 0.45 W LED source. Hydrogen generation by photoreforming of methanol is being one of the most intensely investigated photochemical transformations in pursuing a sustainable, zero waste circular economy. This transformation usually produces a significant amount of gaseous carbon in the form of CO 2 and CO that disqualifies many active photocatalysts as being fully sustainable. Here, we demonstrate the atomically dispersed Cu on TiO 2 composite nanoparticles synthesized by the wet impregnation method that are highly active and selective in hydrogen production by photoreforming of methanol solution. Our photocatalyst exhibits an apparent quantum efficiency of 10% at 365 nm wavelength and the low power 0.45 W light emitting diode (LED) source. The only gaseous product found is molecular hydrogen, whereas all carbon is trapped in the downstream liquid mixture of formaldehyde and formic acid, making the process fully sustainable and clean. We used various experimental techniques and density functional theory calculations (DFT) to characterize our photocatalysts and provide an insight into the exceptional behavior of the Cu/TiO 2 system. A combination of ab initio DFT and X–ray photoelectron spectroscopy (XPS) measurements allowed us to identify the Cu+–Cu0–Cu+ redox cycle under the reaction conditions. Bypassing the Cu2+ oxidation state is crucial to keep the oxidation potential of photogenerated holes low enough to prevent CO 2 generation and keeping all carbon in the liquid phase. This work paves the way toward an efficient and clean generation of hydrogen by photoreforming of methanol over well–established and cheap Cu/TiO 2 photocatalyst. [ABSTRACT FROM AUTHOR]

[Display omitted] • The ultrasound was successfully utilized as a mean of precipitated synthesis of TiO 2. • The ultrasound assisted synthesized TiO 2 samples showed the formation of nanostructures. • The optimization of utilized frequencies and different amplitudes is necessary to alter/tuned the photoactivity. • The additive free photocatalytic selective oxidation of aromatic alcohols to corresponding products was studied. • Our novel ultrasound assisted synthesized TiO 2 showed higher selectivity of products. The research for "green" and economically feasible approaches such as (photo)catalysis especially for biomass valorization such as selective oxidation of biomass derived compounds like aromatic alcohols to corresponding aldehyde by avoiding the harsh reaction conditions and the addition of reagents concentrate the focus of attention the last years. Hence, design and development of novel photocatalyst for the partial selective oxidation is highly desirable. In this research work, ultrasonication of different frequencies (22, 40, 80 kHz) and different amplitudes was utilized as synthesis tool in order to obtain novel materials by precipitation method. The synthesized samples were characterized by using different techniques such as N 2 sorption, TEM, XPS, XRD, thermal analysis, and diffuse reflectance spectroscopy. The synthesized sample by using low ultrasound frequency (22 kHz) and amplitude showed a mixed morphological and structural nature consisting of asymmetric 1-dimensional (nanorods-like), layered nano-structures and not well-defined areas, leading to elevate for metal oxide specific surface areas up to 155 m2/g. The observed 1-D nanostructures have diamentions in the range of 20–60 nm. This sample revealed the highest photo-oxidation efficiency for the selective conversion of two biomass-derived, and more specifically lignin-inspired model compounds, benzyl alcohol and cinnamyl alcohol to benzaldehyde and cinnamyl aldehyde, respectively, and hence the highest yield towards the desired aldehydes. The selective photo-oxidation activity was retained even after 5 photocatalytic cycles, while no leaching of Ti was recorded. [ABSTRACT FROM AUTHOR]

Selective upgrade of lignocellulosic biomass-derived aromatic compounds by photocatalytic oxidation is assumed as a prosperous, environmentally friendly, and cost-effective process. We present for the first time the application of various advantageous titanium oxide nano-photocatalysts for the additives-free selective partial oxidation of benzyl alcohol to benzaldehyde at ambient conditions. The two best-performing materials were found titanate nanotubes and nanocores of anatase surrounded by amorphous titanium hydroxide phase. The results obtained by scavenger tests on top of the DFT calculations led us to conclude that various reactions and active species are responsible by a complex way for materials' photoreactivity. Depending on nanocatalysts' physicochemical features as well as the light irradiation (ultraviolet vs. royal-blue), different mechanisms/oxidation-pathways are photo-catalyzed. Finally, we show that utilizing organic compounds like benzoquinone as scavenger hides risks due to the interactions with the targeted to be converted organic that results in elevated photolytic decomposition even under royal-blue light. [Display omitted] • Novel titanium oxide nanomaterials showed elevated photocatalytic benzyl alcohol oxidation. • The presence of the surface hydroxyl groups affects positively the selectivity. • DFT calculations and scavenger tests showed that various mechanisms are involved. [ABSTRACT FROM AUTHOR]

The designing and synthesis of novel photocatalysts are the most important parts, with TiO 2 -based materials to be consider as prosperous candidates for the selective photo-oxidation of aromatic alcohol. Herein, we established an ultrasound-assisted (500 kHz) precipitation synthetic protocol which led to titanate nanorods of 30 nm maximum length, decorated with nanoclusters of size 1–3 nm. The physicochemical features of the synthesized catalysts were characterized by various techniques. The 1-D nanomaterial obtained at low ultrasound power revealed highest yield towards selective photo-oxidation of benzyl alcohol to benzaldehyde comparing to the material synthesized at higher ultrasound power, in silent, and the commercial TiO 2 -P25. [Display omitted] • Synthesis of one-dimensional titanium dioxide nanorods by an ultrasound assisted precipitation method. • Different powers of ultrasound irradiation (at 500 kHz) led to different physicochemical features. • Photocatalytic selective partial oxidation of benzyl alcohol to benzaldehyde was studied. • The obtained nanocluster-decorated titania nanorods showed high selectivity towards benzaldehyde. [ABSTRACT FROM AUTHOR]