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The co‐electroreduction of CO2 and NOx⁻ (NO3⁻/NO2⁻) to generate formamide (HCONH2) offers an opportunity for downstream chemical and polymer manufacturing decarbonization; however, significant challenges lie in the C‒N coupling and the associated low product selectivity. Herein, p‐block metal oxides are incorporated in copper oxides to provide more accessible active sites for reactant adsorption and activation, tuning the reaction selectivity toward the formamide production. Through in situ Raman and synchrotron‐based infrared spectroscopy measurements, C─N bond formation is demonstrated in real‐time with the CuOx/BiOx catalyst, where the C─N bond is detected via a *CHO and *NH2 intermediates formation, in agreement with the density functional theory calculations. When tested in a flow electrolyzer, a formamide yield rate of 134 ± 11 mmol h−1 gcat−1 is reported, the first report of co‐electroreduction of CO2 and NOx⁻ to formamide beyond conventional H‐cell measurements. These new insights on the C‒N coupling mechanisms and scale‐up capability provide directions for further development of electrocatalysts for the formamide production. [ABSTRACT FROM AUTHOR]

Over 79 % of 6.3 billion tonnes of plastics produced from 1950 to 2015 have been disposed in landfills or found their way to the oceans, where they will reside for up to hundreds of years before being decomposed bringing upon significant dangers to our health and ecosystems. Plastic photoreforming offers an appealing alternative by using solar energy and water to transform plastic waste into value‐added chemical commodities, while simultaneously producing green hydrogen via the hydrogen evolution reaction. This review aims to provide an overview of the underlying principles of emerging plastic photoreforming technologies, highlight the challenges associated with experimental protocols and performance assessments, discuss recent global breakthroughs on the photoreforming of plastics, and propose perspectives for future research. A critical assessment of current plastic photoreforming studies shows a lack of standardised conditions, hindering comparison amongst photocatalyst performance. Guidelines to establish a more accurate evaluation of materials and systems are proposed, with the aim to facilitate the translation of promising fundamental discovery in photocatalysts design. [ABSTRACT FROM AUTHOR]

Perovskite solar cell (PSC) technology is a promising candidate for space applications because of its high power‐to‐weight ratio, low‐cost fabrication process, and good tolerance to high‐energy particle radiation. In this work, perovskite films and resultant high‐efficiency PSCs are assessed under 10 MeV proton radiation at fluences in the range 1e12–1e14 p cm−2, which are equivalent to 1 to 100 years in geostationary orbit (GEO) without any shielding or cover. For the first time, void formation and material ablation are detected on perovskite films, indicating structural damage of the materials under the proton radiation. Furthermore, ions inside the devices especially Au and Pb ions are displaced to underlying layers under the proton bombardment. These lead to the degradation of PSCs to ≈89% of the initial performance (from 24.1% to 21.4%) at the highest dose. The experimental results are supported by previous simulation works with a good fit in all optoelectronic parameters. This study provides insights into the degradation mechanism of PSCs under proton radiation and paves the way for the utilization of PSCs in space applications. [ABSTRACT FROM AUTHOR]

Coupling the hydrogen evolution reaction with plastic waste photoreforming provides a synergistic path for simultaneous production of green hydrogen and recycling of post‐consumer products, two major enablers for establishment of a circular economy. Graphitic carbon nitride (g‐C3N4) is a promising photocatalyst due to its suitable optoelectronic and physicochemical properties, and inexpensive fabrication. Herein, a mechanistic investigation of the structure‐activity relationship of g‐C3N4 for poly(ethylene terephthalate) (PET) photoreforming is reported by carefully controlling its fabrication from a subset of earth‐abundant precursors, such as dicyandiamide, melamine, urea, and thiourea. These findings reveal that melamine‐derived g‐C3N4 with 3 wt.% Pt has significantly higher performance than alternative derivations, achieving a maximum hydrogen evolution rate of 7.33 mmolH2 gcat−1 h−1, and simultaneously photoconverting PET into valuable organic products including formate, glyoxal, and acetate, with excellent stability for over 30 h of continuous production. This is attributed to the higher crystallinity and associated chemical resistance of melamine‐derived g‐C3N4, playing a major role in stabilization of its morphology and surface properties. These new insights on the role of precursors and structural properties in dictating the photoactivity of g‐C3N4 set the foundation for the further development of photocatalytic processes for combined green hydrogen production and plastic waste reforming. [ABSTRACT FROM AUTHOR]

Implementation of proton-exchange membrane water electrolyzers for large-scale sustainable hydrogen production requires the replacement of scarce noble-metal anode electrocatalysts with low-cost alternatives. However, such earth-abundant materials often exhibit inadequate stability and/or catalytic activity at low pH, especially at high rates of the anodic oxygen evolution reaction (OER). Here, the authors explore the influence of a dielectric nanoscale-thin oxide layer, namely Al 2 O 3 , SiO 2 , TiO 2 , SnO 2 , and HfO 2 , prepared by atomic layer deposition, on the stability and catalytic activity of low-cost and active but insufficiently stable Co 3 O 4 anodes. It is demonstrated that the ALD layers improve both the stability and activity of Co 3 O 4 following the order of HfO 2 > SnO 2 > TiO 2 > Al 2 O 3 , SiO 2 . An optimal HfO 2 layer thickness of 12 nm enhances the Co 3 O 4 anode durability by more than threefold, achieving over 42 h of continuous electrolysis at 10 mA cm -2 in 1 m H 2 SO 4 electrolyte. Density functional theory is used to investigate the superior performance of HfO 2 , revealing a major role of the HfO 2 |Co 3 O 4 interlayer forces in the stabilization mechanism. These insights offer a potential strategy to engineer earth-abundant materials for low-pH OER catalysts with improved performance from earth-abundant materials for efficient hydrogen production., (© 2023 The Authors. Small published by Wiley‐VCH GmbH.)

Coupling the hydrogen evolution reaction with plastic waste photoreforming provides a synergistic path for simultaneous production of green hydrogen and recycling of post-consumer products, two major enablers for establishment of a circular economy. Graphitic carbon nitride (g-C 3 N 4 ) is a promising photocatalyst due to its suitable optoelectronic and physicochemical properties, and inexpensive fabrication. Herein, a mechanistic investigation of the structure-activity relationship of g-C 3 N 4 for poly(ethylene terephthalate) (PET) photoreforming is reported by carefully controlling its fabrication from a subset of earth-abundant precursors, such as dicyandiamide, melamine, urea, and thiourea. These findings reveal that melamine-derived g-C 3 N 4 with 3 wt.% Pt has significantly higher performance than alternative derivations, achieving a maximum hydrogen evolution rate of 7.33 mmol H2  g cat -1  h -1 , and simultaneously photoconverting PET into valuable organic products including formate, glyoxal, and acetate, with excellent stability for over 30 h of continuous production. This is attributed to the higher crystallinity and associated chemical resistance of melamine-derived g-C 3 N 4 , playing a major role in stabilization of its morphology and surface properties. These new insights on the role of precursors and structural properties in dictating the photoactivity of g-C 3 N 4 set the foundation for the further development of photocatalytic processes for combined green hydrogen production and plastic waste reforming., (© 2023 The Authors. Small Methods published by Wiley-VCH GmbH.)