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Atmospheric pollution has been recognized as a primary global emergency, especially in large cities and industrial areas. Among the most common harmful pollutants, nitrogen oxides (NOx) are responsible for a plethora of adverse effects, and their effective elimination from air has become an imperative task. In this regard, photocatalysis stands as an attractive technology for NOx degradation, provided that low‐cost and efficient visible ‐light photocatalysts are developed. In this regard, the construction of heterojunctions between energy band‐matched semiconductors is an effective strategy to boost the ultimate material photoactivity. In the present study, green heterocomposites based on MgAlTi layered double hydroxides (LDHs) and graphitic carbon nitride (gCN) are prepared using an amenable and cost‐effective route. A proper modulation of the system characteristics, as demonstrated by a comprehensive investigation, enabled to obtain very attractive DeNOx performances thanks to the efficient construction of MgAlTi/gCN heterojunctions with tailored features. The formation of the target heterocomposites significantly enhances the visible light photoactivity of the pristine LDH, boosting nitrogen monoxide transformation to nitrites/nitrates with a remarkable recycling stability. Overall, the presently reported results open the door to a profitable system exploitation for air purification under real‐world conditions, with considerable impact on both human wellbeing and environmental protection. [ABSTRACT FROM AUTHOR]

In this work, we report the x-ray photoelectron spectroscopy characterization of a novel nanocomposite (photo)electrocatalyst for the oxygen evolution reaction, based on amorphous carbon nitride (aCN) functionalized with CuxO nanoparticles (NPs). The specimen has been fabricated employing two sequential plasma-assisted processes, involving the initial aCN deposition onto conductive glass via magnetron sputtering, followed by carbon nitride functionalization with CuxO (x = 1, 2) NPs by radio frequency-sputtering. The results reported herein include the survey spectrum and the high-resolution C 1s, N 1s, O 1s, Cu 2p, and Cu LMM signals. The most significant spectral features are analyzed and critically discussed. [ABSTRACT FROM AUTHOR]

Layered double hydroxides (LDHs) and graphitic carbon nitride (gCN) are burgeoning multifunctional materials that have attracted a considerable interest as heterogeneous catalysts for environmental remediation. In the present work, we report on the x-ray photoelectron spectroscopy characterization of a representative MgAlTi-LDH/gCN heterocomposite, obtained by a simple mixing of single powdered constituents. Monochromated Al Kα radiation (1486.6 eV) was used as the source of x-ray excitation to acquire both wide-scan spectra and high-resolution signals of the principal element core levels. The main spectral features of the target system are critically examined and discussed in relation to the data related to the pristine MgAlTi-LDH. The obtained results highlight the occurrence of an electronic interplay between the single material constituents, anticipating an enhanced separation of photogenerated charge carriers and an improved activity for photocatalytic applications. The present reported data will serve as comparison for LDH-based materials obtained under various processing conditions for different end-uses. [ABSTRACT FROM AUTHOR]

Nanocomposites based on Pt nanoparticles (NPs) and graphitic carbon nitride (gCN) have emerged as promising (photo)electrocatalysts for sustainable energy production, thanks to the synergistical combination of Pt NPs catalytic performances with the favorable gCN chemicophysical properties. In this work, we have focused on electrophoretic deposition of graphitic carbon nitride on carbon paper and subsequent system functionalization with Pt NPs by means of radio frequency sputtering under mild conditions. A final thermal treatment was performed both in air and under inert atmospheres to assess its influence on Pt oxidation states and the related interplay with ultimate functional performances. The present study is focused on x-ray photoelectron spectroscopy characterization of two representative gCN-Pt nanocomposite specimens, annealed in Ar and in air. In particular, we report the survey spectra and the detailed scans for C 1s, N 1s, O 1s, and Pt 4f regions, analyzing the principal spectral features and comparatively discussing the resulting material properties. [ABSTRACT FROM AUTHOR]

The design and synthesis of low-cost oxygen evolution reaction (OER) photoelectrocatalysts endowed with high activity and durability is of utmost importance for sustainable energy generation via solar-assisted water splitting. In this regard, and in the framework of our recent activities, we have focused on the electrophoretic deposition of graphitic carbon nitride (gCN) specimens containing dispersed NiO nanoaggregates on carbon cloth substrates. In the present study, the attention is devoted to the x-ray photoelectron spectroscopy characterization of a representative gCN–NiO specimen. In particular, we provide an analysis of C 1s, N 1s, O 1s, and Ni 2p regions, discussing in detail the main spectral features. The obtained results, that provide evidence for a direct electronic interplay between the single material components, may serve as a useful comparison for additional research on analogous materials for energy and environmental applications. [ABSTRACT FROM AUTHOR]

Significant efforts have been continuously devoted to the mastering of green catalysts for the oxygen evolution reaction (OER), whose sluggish kinetics prevents a broad market penetration of water splitting as a sustainable route for large-scale hydrogen production. In this extensive scenario, carbon nitride (CN)-based systems are in focus thanks to their favorable characteristics, and, whereas graphitic CN has been largely investigated, the potential of amorphous carbon nitride (a-CNx) systems remains almost entirely unexplored. In this regard, our study presents a novel two-step plasma-assisted route to a-CNx systems comprising ultra-dispersed, i.e. "quasi-atomic" CuxO (x = 1, 2). The target materials were fabricated using an original strategy consisting in the magnetron sputtering of a-CNx on conducting glasses at room temperature, followed by functionalization with low CuxO amounts by radio frequency (RF)-sputtering, and final annealing under an inert atmosphere. The tailoring of the CuxO co-catalyst content and spatial dispersion, as well as the overall composite features as a function of preparative conditions, enabled a direct modulation of the resulting OER performances, rationalized based on the formation of p-n CuxO/a-CNx heterojunctions. The amenable and scalable synthesis approach underscores the practicality of this method to develop (photo)electrocatalysts synergistically integrating the advantages of both constituents, yielding low-cost, green, and stable functional platforms that could contribute to the broader adoption of sustainable energy solutions. [ABSTRACT FROM AUTHOR]

The development of low‐cost and high‐efficiency oxygen evolution reaction (OER) photoelectrocatalysts is a key requirement for H2 generation via solar‐assisted water splitting. In this study, we report on an amenable fabrication route to carbon cloth‐supported graphitic carbon nitride (gCN) nanoarchitectures, featuring a modular dispersion of NiO as co‐catalyst. The synergistic interaction between gCN and NiO, along with the tailoring of their size and spatial distribution, yield very attractive OER performances and durability in freshwater splitting, of great significance for practical end‐uses. The potential of gCN electrocatalysts containing ultra‐dispersed, i. e. "quasi‐atomic" NiO, exhibiting a higher activity than the ones containing nickel oxide nanoaggregates, is further highlighted by their activity even in real seawater. This work suggests that efficient OER catalysts can be designed through the construction of optimized interfaces between transition metal oxides and carbon nitride, yielding inexpensive and promising noble metal‐free systems for real‐world applications. [ABSTRACT FROM AUTHOR]

In the present work, exfoliated graphitic carbon nitride (g‐CN) is immobilized on carbon paper substrates by a simple electrophoretic route, and subsequently decorated with ultra‐low amounts (≈μg/cm2) of Pt nanoparticles (NPs) by cold plasma sputtering. Optimization of preparative conditions allowed a fine tuning of Pt NPs size, loading and distribution and thus a controlled tailoring of g‐CN/Pt interfacial interactions. Modulation of such features yielded g‐CN‐Pt‐based anode materials with appealing activity and stability towards the ethanol oxidation reaction (EOR) in alkaline aqueous solutions, as revealed by electrochemical tests both in the dark and under irradiation. The present results provide new insights on the design of nano‐engineered heterocomposites featuring improved performances thanks to Pt coupling with g‐CN, a low‐cost and environmentally friendly visible light‐active semiconductor. Overall, this work might open attractive avenues for the generation of green hydrogen via aqueous ethanol electrolysis and the photo‐promoted alcohol electrooxidation in fuel cells. [ABSTRACT FROM AUTHOR]

Nanocomposite systems based on iron(III) oxide (Fe2O3) and graphitic carbon nitride (gCN) possess a great potential as photo(electro)catalysts for environmental remediation and energy generation. In this field, a key issue is the fabrication of supported materials directly grown onto suitable substrates and possessing tailored features. In the present study, Fe2O3–gCN nanomaterials are prepared by an innovative two-step strategy, consisting of initial plasma assisted-chemical vapor deposition of iron(III) oxide on conducting glass substrates and subsequent functionalization with low amounts of gCN by a facile electrophoretic deposition process. Attention is dedicated to the use of two different forms of carbon nitride, obtained from melamine or melamine + cyanuric acid, in order to finely tune the resulting material composition. In this work, x-ray photoelectron spectroscopy was used to characterize the pristine Fe2O3 deposit as well as two Fe2O3–gCN composite materials prepared starting from different gCN powders. A detailed analysis of the obtained spectroscopic data reveals the occurrence of a direct electronic interplay between single constituents, dependent on material characteristics. The related results may act as useful guidelines for the design of photo(electro)catalysts endowed with specific properties, of importance for sustainable applications. [ABSTRACT FROM AUTHOR]

Composite materials based on MnO2 deposits functionalized with graphitic carbon nitride (gCN) nanostructures are promising (photo)electrocatalysts for oxygen evolution reaction (OER). Besides the individual properties of the two electrode components, mutual interactions at their interface can also exert a significant influence on functional performances. In this work, MnO2 deposits are synthesized by plasma enhanced-chemical vapor deposition on Ni foam supports and subsequently decorated with two different forms of carbon nitride via electrophoretic deposition. Structural and morphological analyses revealed the formation of β-MnO2 2D structures hierarchically assembled into flowerlike architectures, whose surface appeared decorated by 3D particles built up from gCN nanoflakes. Based on the intimate contact between the two semiconductors, an effective electronic and chemical coupling was established at their interface. In the following, we report on a comparative XPS characterization of a bare MnO2 electrode material and of two MnO2-gCN composite systems prepared from different carbon nitride powders. Survey spectra as well as detailed scans for C 1s, N 1s, O 1s, and Mn 2p regions are presented and critically discussed. [ABSTRACT FROM AUTHOR]

Materials based on graphitic carbon nitride (gCN) have drawn a great deal of attention as (photo)electrocatalysts triggering the oxygen evolution reaction (OER) in H2O splitting processes to yield hydrogen fuel. In this work, nonmonochromatized Mg Kα radiation (1253.6 eV) was used to acquire photoelectron spectroscopy data on gCN-containing composite systems supported on fluorine-doped tin oxide. The investigated materials were prepared via a straightforward decantation route to yield carbon nitride, followed by functionalization with low amounts of nanostructured co-catalysts (CoO, CoFe2O4) through radio frequency-sputtering, and final thermal treatment under an inert atmosphere. Structural and morphological analyses highlighted the formation of composite systems, in which the single constituents, featuring an intimate contact, maintained their chemical identity. This work proposes a data record including both survey scans and high-resolution spectra of C 1s, N 1s, O 1s, Co 2p, and Fe 2p core-levels for three representative specimens comprising bare and functionalized graphitic carbon nitride (gCN, gCN-CoO, and gCN-CoFe2O4). The obtained results, discussed in relation to the different chemical environments for the various elements, will be useful as a comparison for further studies in related fields. [ABSTRACT FROM AUTHOR]