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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]

Solar-driven seawater electrolysis for hydrogen fuel production holds an outstanding potential towards the development of a carbon-neutral and sustainable energy infrastructure, but the development of green, efficient and stable photoelectrocatalysts selectively promoting oxygen evolution remains a formidable challenge. Motivated by this issue, in this work we propose a tailored combination of two economically viable materials, α-Fe2O3 and graphitic carbon nitride (gCN), to fabricate promising anodes – eventually decorated with cobalt phosphate (CoPi) particles – for alkaline seawater photosplitting. The target systems were fabricated via an original multi-step route, involving the plasma-enhanced chemical vapor deposition of iron(III) oxide on conducting glasses, the introduction of gCN in very small amounts by a rapid and facile electrophoretic process, and final annealing in air. A comprehensive characterization revealed the successful fabrication of composites featuring a tailored surface defectivity, a controlled nano-organization, and a close Fe2O3/gCN interfacial contact. After decoration with CoPi, the best performances corresponded to a Tafel slope of ≈100 mV dec−1 and overpotential values enabling us to rule out the competitive hypochlorite formation. In addition, photocurrent densities at 1.23 V vs. RHE showed a nearly 7-fold increase upon Fe2O3 functionalization with both gCN and CoPi. These amenable results, directly dependent on the electronic interplay at Fe2O3/gCN heterojunctions and on CoPi beneficial effects, are accompanied by a remarkable long-term stability, and may open up attractive avenues for clean energy production using natural resources. [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]

In the present contribution, x-ray photoelectron spectroscopy was used to characterize the surface composition and elemental chemical states of graphitic carbon nitride (g-C3N4) materials decorated with highly dispersed noble metals (Au, Ag, or Au + Ag). Samples were prepared through electrophoretic deposition of g-C3N4 on fluorine-doped tin oxide substrates and annealed at 500 °C in Ar. The resulting systems were subsequently functionalized by radio frequency-sputtering and finally annealed again under an Ar atmosphere. Material's structural and morphological characterization revealed an intimate contact of the introduced noble metals with the underlying g-C3N4 matrix. Survey spectra as well as detailed scans for C 1s, N 1s, O 1s, Au 4f, Ag 3d, and Sn 3d regions are presented and critically discussed. The obtained results evidence the presence of highly defective carbon nitride matrices functionalized by low-sized Au nanoaggregates, atomically dispersed Ag, or partially alloyed Au-Ag core/shell nanoparticles. [ABSTRACT FROM AUTHOR]

This article, published in ChemSusChem, discusses a method for creating electrocatalysts for the ethanol oxidation reaction. The researchers used plasma-assisted dispersion to incorporate small amounts of platinum nanoparticles onto graphitic carbon nitride. The resulting system showed enhanced photoactivity and operational stability, which could have implications for sustainable energy production. The article provides more detailed information on the research conducted by A. Gasparotto, C. Maccato, and their colleagues. [Extracted from the article]

In this work, we propose an original and potentially scalable synthetic route for the fabrication of Cu x O-gCN-TiO 2 -Au ( x = 1,2) nanoarchitectures, based on Cu foam anodization, graphitic carbon nitride liquid-phase deposition, and TiO 2 /Au sputtering. A thorough chemico-physical characterization by complementary analytical tools revealed the formation of nanoarchitectures featuring an intimate contact between the system components and a high dispersion of gold nanoparticles. Modulation of single component interplay yielded excellent functional performances in photoactivated hydrogen evolution, corresponding to a photocurrent of ≈-5.7 mA cm -2 at 0.0 V vs. the reversible hydrogen electrode (RHE). These features, along with the very good service life, represent a cornerstone for the conversion of natural resources, as water and largely available sunlight, into added-value solar fuels., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The design and fabrication of eco-friendly and cost-effective (photo)electrocatalysts for the oxygen evolution reaction (OER) is a key research goal for a proper management of water splitting to address the global energy crisis. In this work, we focus on the preparation of supported MnO 2 /graphitic carbon nitride (g-CN) OER (photo)electrocatalysts by means of a novel preparation strategy. The proposed route consists of the plasma enhanced-chemical vapor deposition (PE-CVD) of MnO 2 nanoarchitectures on porous Ni scaffolds, the anchoring of controllable g-CN amounts by an amenable electrophoretic deposition (EPD) process, and the ultimate thermal treatment in air. The inherent method versatility and flexibility afforded defective MnO 2 /g-CN nanoarchitectures, featuring a g-CN content and nano-organization tunable as a function of EPD duration and the used carbon nitride precursor. Such a modulation had a direct influence on OER functional performances, which, for the best composite system, corresponded to an overpotential of 430 mV at 10 mA/cm 2 , a Tafel slope of ≈70 mV/dec, and a turnover frequency of 6.52 × 10 -3 s -1 , accompanied by a very good time stability. The present outcomes, comparing favorably with previous results on analogous systems, were rationalized on the basis of the formation of type-II MnO 2 /g-CN heterojunctions, and yield valuable insights into this class of green (photo)electrocatalysts for end uses in solar-to-fuel conversion and water treatment.