Mariia V. Pavliuk

Two new star-shaped donor–acceptor oligomers, named TxBT and TxNT, with a truxene donor core and either 2,1,3-benzothiadiazole (BT) or a naphtho[1,2- c :5,6- c ′]bis[1,2,5]thiadiazole (NT) unit, respectively, have been developed for photocatalytic hydrogen production.

Organic nanorods have been prepared to be assembled with carbon monoxide dehydrogenase for photobiocatalytic CO₂ reduction. The surfactants used to synthesize organic nanorods have shown significant effect on the performance of biohybrid assemblies.

Photobiocatalytic CO2 reduction represents an attractive approach for conversion of solar light and abundant resources to value-added chemicals. However, the design of suitable systems requires a detailed understanding of the interaction between artificial photosensitizer and biocatalyst interface. In this work, we investigate the effect of surfactant charge utilized in the preparation of a phenoxazine-based organic molecule nanorods photosensitizer on the interaction with the carbon monoxide dehydrogenase II from Carboxydothermus hydrogenoformans within biohybrid assemblies for photobiocatalytic CO2 reduction into CO. Electrophoretic mobility shift assay in pair with cryogenic electron microscopy (Cryo-EM) and detailed physicochemical characterization are conducted to understand the interaction at the biohybrid interface in order to suggest the strategy for future functionalization of nanoparticles that fulfill the needs from biocatalyst for green fuel production.

Small molecule heterojunction nanoparticles based on a phenoxazine photosensitizer and a non-fullerene acceptor ITIC have been developed for photocatalytic hydrogen production.

Production of renewable fuels from solar energy and abundant resourses, such as water and carbon dioxide, via photocatalytic reactions is seen as a promising strategy to adequately address the climate challenge. Photocatalytic systems based on organic polymer nanoparticles (PNPs) are seen as one avenue to transform solar energy into hydrogen and other solar fuels. Semiconducting PNPs are light-harvesting materials with exceptional optical properties, photostability, low cost and low cytotoxity, whose performance surpasses conventional organic dyes and inorganic semiconductors. This review introduces the optimization strategies for the preparation methods of PNP via cocatalyst loading and morphology tuning. We present an analysis on how the preparative methods will impact the physico-chemical properties of these materials, and thus the catalytic activity. A list of experimental techniques is presented for characterization of the physico-chemical properties (optical, morphological, electrochemical and catalytic properties) of PNPs. We provide detailed analysis of PNP photochemistry during photocatalysis with focus on the mechanistic understanding of processes of internal charge generation and transport to the catalyst. This tutorial review provides the reader with the guidelines on current strategies used to optimize PNP performance highlighting the future directions of polymer nano-photocatalysts development.

A biomimetic model complex of the [FeFe]-hydrogenase active site (FeFeOH) with an ethylene bridge and a pendant hydroxyl group has been synthesized, characterized and evaluated as catalyst for the light-driven hydrogen production. The interaction of the hydroxyl group present in the complex with 3-isocyanopropyltriethoxysilane provided a carbamate triethoxysilane bearing a diiron dithiolate complex (NCOFeFe), thus becoming a potentially promising candidate for anchoring on heterogeneous supports. As a proof of concept, the NCOFeFe precursor was anchored by a grafting procedure into a periodic mesoporous organosilica with ethane bridges (EthanePMO@NCOFeFe). Both molecular and heterogenized complexes were tested as catalysts for light-driven hydrogen generation in aqueous solutions. The photocatalytic conditions were optimized for the homogenous complex by varying the reaction time, pH, amount of the catalyst or photosensitizer, photon flux, and the type of light source (light-emitting diode (LED) and Xe lamp). It was shown that the molecular FeFeOH diiron complex achieved a decent turnover number (TON) of 70 after 6 h, while NCOFeFe and EthanePMO@NCOFeFe had slightly lower activities showing TONs of 37 and 5 at 6 h, respectively.

The heterometallic complexes (NH₄)₂[Co(H₂O)₆]₂[V₁₀O₂₈]⋅4 H₂O (1) and (NH₄)₂[Co(H₂O)₅(β‐HAla)]₂[V₁₀O₂₈]⋅4 H₂O (2) have been synthesized and used for the preparation of mixed oxides as catalysts for water oxidation. Thermal decomposition of 1 and 2 at relatively low temperatures (2O₆/V₂O₅ (3) and Co₂V₂O₇/V₂O₅ (4). The complexes (1, 2) and heterogeneous materials (3, 4) act as catalysts for photoinduced water oxidation. A modification of the thermal decomposition procedure allowed the deposition of mixed metal oxides (MMO) on a mesoporous TiO₂ film. The electrodes containing Co/V MMOs in TiO₂ films were used for electrocatalytic water oxidation and showed good stability and sustained anodic currents of about 5 mA cm⁻² at 1.72 V versus relative hydrogen electrode (RHE). This method of functionalizing TiO₂ films with MMOs at relatively low temperatures (<500 °C) can be used to produce other oxides with different functionality for applications in, for example, artificial photosynthesis.

The influence of Mo content in the solid solutions of Bi_1−x/3V_1−xMo_xO₄ (x = 0.05–0.20) on the morphology, band gap, structure and light-driven water oxidation properties has been studied by SEM, powder XRD and vibrational spectroscopy.