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The present study proposes a laser irradiation method to superficially reduce BiVO4 photoelectrodes and boost their water oxidation reaction performance. The origin of this enhanced performance toward oxygen evolution reaction (OER) was studied using a combination of a suite of structural, chemical, and mechanistic advanced characterization techniques including X-ray photoelectron (XPS), X-ray absorption spectroscopy (XAS), electrochemical impedance spectroscopy (EIS), and transient absorption spectroscopy (TAS), among others. We found that the reduction of the material is localized at the surface of the sample and that this effect creates effective n-type doping and a shift to more favorable energy band positions toward water oxidation. This thermodynamic effect, together with the change in sample morphology to larger and denser domains, results in an extended lifetime of the photogenerated carriers and improved charge extraction. In addition, the stability of the reduced sample in water was also confirmed. All of these effects result in a two-fold increase in the photocurrent density of the laser-treated samples.

The design of an active, effective, and economically viable catalyst for CO 2 conversion into value-added products is crucial in the fight against global warming and energy demand. We have developed very efficient catalysts for reverse water-gas shift (rWGS) reaction. Specific conditions of the synthesis by combustion allow the obtention of macroporous materials based on nanosized Ni particles supported on a mixed oxide of high purity and crystallinity. Here, we show that Ni/La-doped CeO 2 catalysts�with the "right" Ni and La proportions�have an unprecedented catalytic performance per unit mass of catalyst for the rWGS reaction as the first step toward CO 2 valorization. Correlations between physicochemical properties and catalytic activity, obtained using a combination of different techniques such as X-ray and neutron powder diffraction, Raman spectroscopy, in situ near ambient pressure X-ray photoelectron spectroscopy, electron microscopy, and catalytic testing, point out to optimum values for the Ni loading and the La proportion. Density functional theory calculations of elementary steps of the reaction on model Ni/ ceria catalysts aid toward the microscopic understanding of the nature of the active sites. This finding offers a fundamental basis for developing economical catalysts that can be effectively used for CO 2 reduction with hydrogen. A catalyst based on Ni 0.07 / (Ce 0.9 La 0.1 O x ) 0.93 shows a CO production of 58 × 10 −5 mol CO •g cat −1•s −1 (700 °C, H 2 /CO 2 = 2; selectivity to CO > 99.5), being stable for 100 h under continuous reaction.

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Metal halide perovskites have shown great potential for lighting. However, their low stability under irradiation/thermal stress and/or ambient storage conditions are critical for light‐emitting diodes (LEDs). Among the stabilization strategies, ligand surface modification is effective toward stable perovskites, but the dynamic ligand adsorption/desorption process on the surface is a limiting factor. Herein, a new family of biogenic and amphiphilic capping agents, phosphatidyl‐L‐serine (Ptd‐L‐Ser), combining stronger multibinding motifs compared to conventional capping agents has led to superior CsPbBr3 (CsPbBr3‐Ptd‐L‐Ser) with significantly enhanced stability upon storage/heating/water, keeping excellent photoluminescence quantum yields of ≈80% over half year. Spectroscopic/theoretical studies reveal that the origin of this behavior is the increased exciton binding energy associated to the versatility of multiple bindings. This results in CsPbBr3‐Ptd‐L‐Ser nanocrystals‐based green‐LEDs featuring excellent stabilities of >700 h (20 mA) and >200 h (100 mA) that strongly contrast with the reference devices with pristine CsPbBr3 nanocrystals (120 h (20 mA) and 27 h (100 mA)). White LEDs (WLEDs) with chromaticity coordinates of (0.34, 0.33) and high luminous efficiency of 76 lm W–1, keeping stable over weeks, are further demonstrated under continuous operational conditions, thereby suggesting CsPbBr3‐Ptd‐L‐Ser nanocrystals can be a potential candidate for commercial WLED technology.