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The molecular single-source precursor (SSP) route has emerged as a promising avenue for synthesizing highly efficient electro(pre)catalysts tailored for both oxygen evolution (OER) and organic electrooxidation reactions. This study introduces a novel [CoII(PyHS)4(OTf)2] molecular complex, offering a facile route to access the nanocrystalline Co9S8 phase. Upon application in alkaline OER, Co9S8 displayed remarkably high electrocatalytic activity across various metrics, including overpotentials, Tafel slopes, faradaic efficiency, charge transfer resistance, turnover frequency, electrochemical surface area, Co-redox active sites, and long-term stability at industrially relevant current densities (for 80 h at 100 mA cm−2) outperforming its Co-based counterparts under identical conditions. In-depth analysis employing several ex situ techniques revealed the complete leaching of sulfur and irreversible reconstruction of Co9S8 into a cobalt oxyhydroxide active phase during the OER. Moreover, quasi in situ Raman spectroscopy provided insights into the presence of CoIVO2 active species under operational OER conditions, along with the formation of the Co superoxide intermediate. Beyond OER applications, the Co9S8-derived active phase demonstrated notable efficiency in catalyzing the selective oxidation of biomass-derived glycerol and furan-2-carboxaldehyde to formate and furan-2-carboxylic acid, respectively, achieving yields exceeding 80%, with excellent reusability. A full hybrid-water electrolysis cell has been developed, wherein biomass valorization with Co9S8, coupled with H2 production, resulted in a significant improvement in energy efficiency compared to conventional water-splitting. [ABSTRACT FROM AUTHOR]

The suitability of electron‐rich bis‐silylenes, specifically the neutral chelating [SiII(Xant)SiII] ligand (SiII=PhC(NtBu)2Si, Xant=9,9‐dimethylxanthene) and the anionic [SiII(NAcrid)SiII)]− pincer ligand (NAcrid=2,7,9,9‐tetramethylacridane), has been successfully probed to stabilize monovalent bis‐silylene‐supported aluminium complexes (aluminylenes). At first, the unprecedented aluminium(III) iodide precursors [SiII(Xant)SiII]AlI2+ I−1 and [SiII(NAcrid)SiII)]AlI22 were synthesized using AlI3 and [SiII(Xant)SiII] or [SiII(NAcrid)SiII)]Li(OEt2)], respectively, and structurally characterized. While reduction of 1 with KC8 led merely to unidentified products, the dehalogenation of 2 afforded the dimer of the desired {[SiII(NAcrid)SiII)]Al:} aluminylene with a four‐membered SiIV2AlIII2 ring. Remarkably, the proposed aluminylene intermediates [SiII(Xant)SiII]AlII and {[SiII(NAcrid)SiII)]Al:} could be produced through reaction of 1 and 2 with Collman's reagent, K2Fe(CO)4, and trapped as AlI:→Fe(CO)4 complexes 5 and 6, respectively. While 6 is stable in solution, 5 loses one CO ligand in solution to afford the silylene‐ and aluminylene‐coordinated iron(0) complex 7 from an intramolecular substitution reaction. The electronic structures of the novel compounds were investigated by Density Functional Theory calculations. [ABSTRACT FROM AUTHOR]

Transition‐metal nanoparticles hold great promise as electrocatalysts for alkaline hydrogen evolution reaction (HER), however, addressing the simultaneous challenges of ensuring sufficient active sites, promoting favorable water dissociation, and optimizing binding energy toward hydrogen intermediates remains a formidable task. To overcome these hurdles, a novel gaseous hydrogen engineering strategy is proposed by in situ embedding cobalt nanoparticles within a samarium hydride matrix (Co/SmH2) via hydrogen‐induced disproportionation of SmCo5 particles for efficient alkaline HER. The as‐designed Co/SmH2 delivered an overpotential as low as 252 mV at 100 mA cm−2, surpassing the performance of pristine Co by 100 mV. Notably, this catalyst lasts remarkably long maintaining a durability at ≈500 mA cm−2 for 120 h. A combination of in situ Raman spectroscopy, in situ X‐ray absorption spectroscopy, density functional theory calculation and post‐HER characterizations unambiguously unveiled that the surface SmH2 transforms into samarium (hydr)oxide during electrocatalysis. This transformation not only inhibits the aggregation of the ultrafine cobalt nanoparticles but also significantly enhances the water dissociation and optimizes the binding energy of active cobalt species toward hydrogen intermediate, resulting in concurrent improvement of kinetics, thermodynamics, and stability of the HER process. [ABSTRACT FROM AUTHOR]

The urgent need for efficient oxygen evolution reaction (OER) catalysts has led to the development and publication of many heterostructured catalysts. The application of such catalysts with multiple phases tremendously increases the material design dimensions, and numerous interface‐related effects can tune the OER performance. In this regard, multiple of these heterostructured electrodes show remarkable OER activities. However, it is not clear if these carefully designed interfaces remain under prolonged OER conditions. Herein, a molecular approach is used to synthesize four different nickel‐iron phosphide (heterostructured) materials and deposit them on fluorine‐doped tin oxide and nickel foam electrodes. The OER performance of the eight electrodes and the reconstruction of the four materials is investigated by in‐situ spectroscopy after one day of operation, enabled by a freeze‐quench approach. The most active electrode is also applied under industrial OER conditions and for the value‐added oxidation of alcohols to ketones. Before catalysis, this electrode comprises crystalline 4 nm nickel phosphide particles on an amorphous iron phosphide matrix. However, after 24 h, a homogenous nickel‐iron oxyhydroxide phase has formed. This work questions to which extent the design of heterostructures is a suitable strategy for non‐noble metal OER catalysis. [ABSTRACT FROM AUTHOR]

Nickel mesh (NM) is used in industrial alkaline water electrolyzers due to its cost‐effectiveness and conductivity. However, the decisive factors that advance the efficiency and sustainability of such electrodes are only partially understood. Herein, an efficient NM‐based electrocatalyst for the oxygen evolution reaction is developed via a single‐step nitridation route on a commercially used NM substrate and sheds light on the role of reconstruction and iron content to boost catalyst performance and durability. Remarkably, the activated Ni3N/NM catalyst required an overpotential of 0.46 V to deliver 1 A cm−2 in ambient conditions (1 M KOH, 25 °C). This overpotential decreases substantially to 0.28 V in industrially relevant conditions (6 M KOH, 85 °C) and is maintained for 235 h. Ni3N/NM partially transformed into NiFe layered (oxy)hydroxide in both conditions, while the active structure's Fe content is reconstruction condition dependent (temperature and KOH concentration). Electrodes reconstructed under industrially relevant conditions performed better than ambient reconstructed ones due to a more pronounced iron‐incorporation from KOH and the evolution of porous morphologies. In industrial environments, activated Ni3N/NM excels in selectively converting benzyl alcohol to benzoic acid, achieving an impressive yield of 96%. [ABSTRACT FROM AUTHOR]

Atomic layer deposition was applied on mesoporous silica to synthesize a highly dispersed gallium oxide catalyst. This system was used as starting material to investigate different loadings of nickel in the dehydrogenation of propane under industrially relevant, Oleflex‐like conditions. The formation of NiGa alloys was confirmed by X‐ray diffraction analysis and electron microscopy. Surprisingly, the nanoalloys enhanced the selectivity towards C3H6 while decreasing the tendency for coking. Herein, in situ thermogravimetry, and measured mass fractions of carbon revealed that the coking rate was reduced by over 50 % compared to the pristine gallium oxide. Generally, the increased selectivity can be explained by the partial hydrogenation and reduction of the gallium oxide surface. The optimum temperature for the removal of deposited carbon was evaluated by a temperature programmed oxidation. Finally, the best‐performing Ni−GaOx catalyst was employed in a cycled experiment with periodic reaction and regeneration tests. After regeneration, the selected Ni−GaOx catalyst provided a higher yield of propylene compared to the unmodified gallium oxide. [ABSTRACT FROM AUTHOR]

Iron‐based (pre)catalysts have attracted enormous attention for various electrooxidation reactions due to the low cost, high abundance, and multiple accessible redox states of iron. Herein, a well‐defined helical iron borophosphate (LiFeBPO) is developed as an electro(pre)catalyst for the oxygen evolution reaction (OER) and selective alcohol oxidation. When deposited on nickel foam (NF), LiFeBPO exhibits an exceptional OER performance at ambient conditions attaining a current density of 100 mA cm−2 at ≈276 mV overpotential in 1 m KOH. Notably, this anode sustains durable alkaline water electrolysis at 500 mA cm−2 for over 330 h under industrial conditions (6 m KOH and 85 °C). In –situ and ex situ investigations reveal a deep reconstruction of LiFeBPO during OER, which transforms into a 3D open porous skeleton assembled by ultrasmall, low‐crystalline α‐FeOOH nanoparticles (interfacing with NiOOH of NF). This structure contributes to exposing accessible surface active sites, as well as accelerating mass transport and bubble detachment. Moreover, this electrode also catalyzes the electrooxidation of alcohols (methanol, ethylene glycol, and glycerol) to formic acid (FA) with high selectivity and full conversion. This study provides promising solutions for designing suitable anodes for the simultaneous production of green hydrogen fuel and value–added FA from electrooxidation reactions. [ABSTRACT FROM AUTHOR]

The quest to develop efficient electrocatalysts for water‐splitting is still an ongoing challenge. Intense efforts have been dedicated over the years to design effective methods to improve the electrocatalytic performances. In recent times, the single‐source (molecular) precursor (SSP) approach has gained enormous attention from the scientific community as it operates at low temperatures and leads to the formation of unique nanostructured materials, with fine‐tuned chemical and physical properties, resulting in high and stable catalytic activities. Herein, the recent developments in molecule‐to‐material chemistry and their applications toward the oxygen evolution reaction, hydrogen evolution reaction, and overall water‐splitting are summarized. Furthermore, the review focuses on understanding the reconstruction process of the SSP‐derived materials and the adopted techniques (in situ and ex situ) to obtain insights into the active structures for catalysis. The future possibilities of applying these materials for value‐added organic electro‐oxidation/reduction reactions are also explored. [ABSTRACT FROM AUTHOR]

Four commercial titanium dioxide (TiO2) photocatalysts, namely P25, P90, PC105, and PC500, were immobilized onto steel plates using a sol-gel binder and investigated for phenol degradation under 365 nm UV-LED irradiation. High-performance liquid chromatography (HPLC) and total organic carbon (TOC) analyses were performed to study the impact of three types of oxygen sources (air, dispersed synthetic air, and hydrogen peroxide) on the photocatalytic performance. The photocatalyst films were stable and there were significant differences in their performance. The best result was obtained with the P90/UV/H2O2 system with 100% degradation and about 70% mineralization within 3 h of irradiation. The operating conditions varied, showing that water quality is crucial for the performance. A wastewater treatment plant was developed based on the lab-scale results and water treatment costs were estimated for two cases of irradiation: UV-LED (about 600 EUR/m3) and sunlight (about 60 EUR/m3). The data show the high potential of immobilized photocatalysts for pollutant degradation under advanced oxidation process (AOP) conditions, but there is still a need for optimization to further reduce treatment costs. [ABSTRACT FROM AUTHOR]

Cobalt‐iron oxyhydroxides (CoFeOOHx) are among the most active catalysts for the oxygen evolution reaction (OER). However, their redox behavior and the electronic and chemical structure of their active sites are still ambiguous. To shed more light on this, the complete and rapid reconstruction of four helical cobalt‐iron borophosphates with different Co:Fe ratios into disordered cobalt‐iron oxyhydroxides can be achieved, which are electrolyte‐penetrable and thus most transition metal sites can potentially participate in the OER. To track the redox behavior and to identify the active structure, quasi in situ X‐ray absorption spectroscopy is applied. Iron in high oxidation states ≥ IV (Fe4+) and its substantial redox behavior with an average oxidation state of around 2.8 to above 3.2 is detected. Furthermore, a 6% contraction of the Fe‐O bond length compared to Fe3+OOH references is observed during OER and a strong distortion of the [MO6] octahedra is identified. It is hypothesized that this bond contraction is caused by the presence of oxyl radicals and that di‐µ‐oxyl radical bridged cobalt‐iron centers are the active sites. It is anticipated that the detailed electronic and structural description can substantially contribute to the debate on the nature of the active site in bimetallic iron‐containing OER catalysts. [ABSTRACT FROM AUTHOR]

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Diiron cofactors in enzymes perform diverse challenging transformations. The structures of high valent intermediates (Q in methane monooxygenase and X in ribonucleotide reductase) are debated since Fe−Fe distances of 2.5–3.4 Å were attributed to "open" or "closed" cores with bridging or terminal oxido groups. We report the crystallographic and spectroscopic characterization of a FeIII2(μ‐O)2 complex (2) with tetrahedral (4C) centres and short Fe−Fe distance (2.52 Å), persisting in organic solutions. 2 shows a large Fe K‐pre‐edge intensity, which is caused by the pronounced asymmetry at the TD FeIII centres due to the short Fe−μ−O bonds. A ≈2.5 Å Fe−Fe distance is unlikely for six‐coordinate sites in Q or X, but for a Fe2(μ‐O)2 core containing four‐coordinate (or by possible extension five‐coordinate) iron centres there may be enough flexibility to accommodate a particularly short Fe−Fe separation with intense pre‐edge transition. This finding may broaden the scope of models considered for the structure of high‐valent diiron intermediates formed upon O2 activation in biology. [ABSTRACT FROM AUTHOR]

The direct hydrogenation of CO2 to methanol is an attractive approach to employ the greenhouse gas as a chemical feedstock. However, the commercial copper catalyst, used for methanol synthesis from CO‐rich syngas, suffers from deactivation at elevated CO2 partial pressure. An emerging alternative is represented by In2O3 as it withstands the hydrothermal conditions induced by the reverse water‐gas shift reaction. The active sites for the adsorption of CO2 and the subsequent conversion into methanol were shown to be oxygen vacancies on the surface of In2O3. In this study, N2O was utilized as a probe molecule to quantify the number of vacancies on indium oxide catalysts. The number of inserted oxygen atoms could be correlated to the respective CO2 hydrogenation activity. Furthermore, the atomic efficiency of indium was enhanced by applying atomic layer deposition of indium oxide on ZrO2. [ABSTRACT FROM AUTHOR]

For the transition towards greener biorefineries with reduced waste, valorization of lignin to drop‐in chemicals instead of their combustion for energy purposes is a key issue for future processes. In this context, lignin should be extracted from lignocellulosic biomass (LCB) and fragmented into smaller units, followed by catalytic funneling to fine chemicals. In this review, we report on the classical approaches for lignin valorization from LCB: thermal treatments, solvolytic valorization, acid‐catalyzed process, and base‐catalyzed process. We also provide the reader with the modern approach of lignin valorization that led to an integrated LCB biorefinery. The performance of different solid catalysts in lignin‐first approach via reductive or oxidative catalytic fractionation at different conditions is discussed in detail. [ABSTRACT FROM AUTHOR]

In this contribution, a simple method for the screening of photocatalytic activity of catalyst materials is presented. The method is based on two steps: the immobilization of the photocatalyst and the subsequent testing of their photocatalytic activity, using the gas evolution at the solid‐liquid interface. Up to four catalysts can be tested under the same conditions. The observed gas evolution for selected photocatalysts is consistent with trends reported in the literature from conventional photocatalytic reactors. [ABSTRACT FROM AUTHOR]

The oxygen evolution reaction (OER) and the value‐added oxidation of renewable organic substrates are critical to supply electrons and protons for the synthesis of sustainable fuels. To meet industrial requirements, new methods for a simple, fast, environmental‐friendly and cheap synthesis of robust, self‐supported and high surface area electrodes are required. Herein, a novel in‐liquid plasma (plasma electrolysis) approach for the growth of hierarchical nanostructures on nickel foam is reported on. Under morphology retention, iron can be doped into this high surface area electrode. For the oxidation of 5‐(hydroxymethyl)furfural and benzyl alcohol, the iron‐free, plasma‐treated electrode is more suitable reaching current densities up to 800 mA cm−2 with Faradaic efficiencies above 95%. For the OER, the iron‐doped nickel foam electrode reaches the industrially relevant current density of 500 mA cm−2 at 1.473 ± 0.013 VRHE (60 °C) and shows no activity decrease over 140 h. The different effects of iron doping are rationalized using methanol probing and in situ Raman spectroscopy. Furthermore, the intrinsic activity is separated from the number of active sites, and, for the organic oxidation reactions, diffusion limitations are revealed. The authors anticipate that the plasma modified nickel foam will be suitable for various (electro)catalytic processes. [ABSTRACT FROM AUTHOR]

The elusive plumbylone {[SiII(Xant)SiII]Pb0} 3 stabilized by the bis(silylene)xanthene chelating ligand 1, [SiII(Xant)SiII=PhC(NtBu)2Si(Xant)Si(NtBu)2CPh], and its isolable carbonyl iron complex {[SiII(Xant)SiII]Pb0Fe(CO)4} 4 are reported. The compounds 3 and 4 were obtained stepwise via reduction of the lead(II) dibromide complex {[SiII(Xant)SiII]PbBr2} 2, prepared from the bis(silylene)xanthene 1 and PbBr2, employing potassium naphthalenide and K2Fe(CO)4, respectively. While the genuine plumbylone 3 is rather labile even at −60 °C, its Pb0→Fe(CO)4 complex 4 turned out to be relatively stable and bottleable. However, solutions of 4 decompose readily to elemental Pb and {[SiII(Xant)SiII]Fe(CO)3} 5 at 80 °C. Reaction of 4 with [Rh(CO)2Cl]2 leads to the formation of the unusual dimeric [(OC)2RhPb(Cl)Fe(CO)4] complex 6 with trimetallic Rh−Pb−Fe bonds. The molecular and electronic structures of 3 and 4 were established by Density Functional Theory (DFT) calculations. [ABSTRACT FROM AUTHOR]

White phosphorus (P4) undergoes degradation to P2 moieties if exposed to the new N,N‐bis(silylenyl)aniline PhNSi21 (Si=Si[N(tBu)]2CPh), furnishing the first isolable 2,5‐disila‐3,4‐diphosphapyrrole 2 and the two novel functionalized Si=P doubly bonded compounds 3 and 4. The pathways for the transformation of the non‐aromatic 2,5‐disila‐3,4‐diphosphapyrrole PhNSi2P22 into 3 and 4 could be uncovered. It became evident that 2 reacts readily with both reactants P4 and 1 to afford either the polycyclic Si=P‐containing product [PhNSi2P2]2P23 or the unprecedented conjugated Si=P−Si=P−Si=NPh chain‐containing compound 4, depending on the employed molar ratio of 1 and P4 as well as the reaction conditions. Compounds 3 and 4 can be converted into each other by reactions with 1 and P4, respectively. All new compounds 1–4 were unequivocally characterized including by single‐crystal X‐ray diffraction analysis. In addition, the electronic structures of 2–4 were established by Density Functional Theory (DFT) calculations. [ABSTRACT FROM AUTHOR]

Based on the low‐cost and relatively high catalytic activity, considerable efforts have been devoted towards developing redox‐active transition metal (TM)‐oxygen electrocatalysts for the alkaline oxygen evolution reaction (OER) while the role of redox‐inactive alkaline earth metals has often been neglected in OER. Herein, for the first time, we developed a novel ternary intermetallic CaFe6Ge6 precatalyst, whose surface rapidly transforms into a porous ultrathin Ca−Fe−O heteroshell structure during alkaline OER through the oxidative leaching of surficial Ge. Benefiting from synergistic effects, this highly efficient OER‐active material with distinct Ca−Fe−O layers has a large electrochemical surface area and more exposed active Fe sites than a Ca‐free FeOx phase. Also, the presence of Ca in Ca−Fe−O is responsible for the enhanced transport and activation of hydroxyls and related OER reaction intermediate as unequivocally illustrated by a combination of quasi in‐situ Raman spectroscopy and various ex‐situ methods. [ABSTRACT FROM AUTHOR]

New types of metal‐free white phosphorus (P4) activation are reported. While the phosphine‐silylene‐substituted dicarborane 1, CB‐SiP (CB=ortho‐C,C′‐C2B10H10, Si=PhC(tBuN)2Si, P=P[N(tBu)CH2]2), activates white phosphorus in a 2 : 1 molar ratio to yield the P5‐chain containing species 2, the analogous bis(silylene)‐substituted compound 3, CB‐Si2, reacts with P4 in the molar ratio of 2 : 1 to furnish the first isolable 1,3‐diphospha‐2,4‐disilabutadiene (Si=P−Si=P‐containing) compound 4. For the latter reaction, two intermediates having a CB‐Si2P4 and CB‐Si2P2 core could be observed by multinuclear NMR spectroscopy. The compounds 2 and 4 were characterized including single‐crystal X‐ray diffraction analyses. Their electronic structures and mechanisms were investigated by density functional theory calculations. [ABSTRACT FROM AUTHOR]

The development of novel earth‐abundant metal‐based catalysts to accelerate the sluggish oxygen evolution reaction (OER) is crucial for the process of large‐scale production of green hydrogen. To solve this bottleneck, herein, a simple one‐pot colloidal approach is reported to yield crystalline intermetallic nickel silicide (Ni2Si), which results in a promising precatalyst for anodic OER. Subsequently, an anodic‐coupled electrosynthesis for the selective oxidation of organic amines (as sacrificial proton donating agents) to value‐added organocyanides is established to boost the cathodic reaction. A partial transformation of the Ni2Si intermetallic precatalyst generates a porous nickel(oxy)hydroxide phase modified with oxidic silicon species as unequivocally demonstrated by a combination of quasi in situ Raman and X‐ray absorption spectroscopy as well as ex situ methods. The activated form of the catalyst generates a geometric current density of 100 mA cm−2 at an overpotential (η100) of 348 mV displaying long‐term durability over a week and high efficiency in paired electrolysis. [ABSTRACT FROM AUTHOR]

The atomic layer deposition of gallium and indium oxide was investigated on mesoporous silica powder and compared to the related aluminum oxide process. The respective oxide (GaOx, InOx) was deposited using sequential dosing of trimethylgallium or trimethylindium and water at 150 °C. In-situ thermogravimetry provided direct insight into the growth rates and deposition behavior. The highly amorphous and well-dispersed nature of the oxides was shown by XRD and STEM EDX-mappings. N2 sorption analysis revealed that both ALD processes resulted in high specific surface areas while maintaining the pore structure. The stoichiometry of GaOx and InOx was suggested by thermogravimetry and confirmed by XPS. FTIR and solid-state NMR were conducted to investigate the ligand deposition behavior and thermogravimetric data helped estimate the layer thicknesses. Finally, this study provides a deeper understanding of ALD on powder substrates and enables the precise synthesis of high surface area metal oxides for catalytic applications. [ABSTRACT FROM AUTHOR]

Herein, we report the efficient degradation of N2O with a well‐defined bis(silylene)amido iron complex as catalyst. The deoxygenation of N2O using the iron silanone complex 4 as a catalyst and pinacolborane (HBpin) as a sacrificial reagent proceeds smoothly at 50 °C to form N2, H2, and (pinB)2O. Mechanistic studies suggest that the iron–silicon cooperativity is the key to this catalytic transformation, which involves N2O activation, H atom transfer, H2 release and oxygenation of the boron sites. This approach has been further developed to enable catalytic reductions of nitro compounds, producing amino‐boranes with good functional‐group tolerance and excellent chemoselectivity. [ABSTRACT FROM AUTHOR]

The monoatomic zero‐valent tin complex (stannylone) {[SiII(Xant)SiII]Sn0} 5 stabilized by a bis(silylene)xanthene ligand, [SiII(Xant)SiII=PhC(NtBu)2Si(Xant)Si(NtBu)2CPh], and its bis‐tetracarbonyliron complex {[SiII(Xant)SiII]Sn0[Fe(CO)4]2} 4 are reported. The stannylone 5 bearing a two‐coordinate zero‐valent tin atom is synthesized by reduction of the precursor 4 with potassium graphite. Compound 4 results from the SnII halide precursor {[SiII(Xant)SiII]SnIICl}Cl 2 or {[SiII(Xant)SiII]SnBr2} 3 through reductive salt‐metathesis reaction with K2Fe(CO)4. According to density functional theory (DFT) calculations, the highest occupied molecular orbital (HOMO) and HOMO‐1 of 5 correspond to a π‐type lone pair with delocalization into both adjacent vacant orbitals of the SiII atoms and a σ‐type lone pair at the Sn0 center, respectively, indicating genuine stannylone character. [ABSTRACT FROM AUTHOR]

The reactivity of the 1,4‐substituted bis(silylenyl)terphenylene 1, 1,4‐[ortho‐(LSi)C6H4]2C6H4, (L=RC(NtBu)2, R=Ph, Mes) towards CS2 is reported. It results in a dearomatization of the phenylene ring, affording the 1,3‐substituted cyclohexadiene derivative 2. According to DFT calculations, a transient silene containing a Si=C bond capable of π(C=C) addition at the aromatic phenylene ring is a key intermediate. In contrast, addition of CS2 to the biphenyl‐substituted mono‐silylene ortho‐(LSi)C6H4‐C6H53 leaves the aromatic π‐system intact and forms, in a [1+2] cycloaddition reaction, the corresponding thiasilirane 4 with a three‐membered SiSC ring. Further experimental studies led to the isolation of the novel mesoionic five‐membered Si2S2C heterocycle 6, which reacts with CS2 under C−C bond formation. All isolated new compounds were fully characterized and their molecular structures determined by single‐crystal X‐ray diffraction analyses. [ABSTRACT FROM AUTHOR]

Following the example of photovoltaics, one approach to large‐scale photocatalytic hydrogen production is the irradiation of a correspondingly large catalyst area. Paper production is a process in which large areas can already be produced based on the main component: cellulose. Herein, the TiO2 photocatalyst modification PC500, which also uses platinum nanoparticles as a cocatalyst, is supported in two different ways using cellulose. On the one hand, the catalyst is fixed to the surface of a commercial filter paper and, on the other hand, a photocatalytic paper is produced. For comparison, the catalyst is immobilized by means of drop coating using Nafion and measured as a suspension. The cellulose‐stabilized films are active and hydrogen production is comparable with the activity obtained from the drop‐coating method. The experiments show that the aggregation behavior of cellulose can be used to produce photocatalytically active films. The preparation is easy and can be applied to different kinds of (photo)catalysts. Although the films are very active, their stability during reaction due to swelling and hydrogen production must be further improved. [ABSTRACT FROM AUTHOR]