Rationally designing active and durable catalysts for the oxygen evolution reaction (OER) is of primary importance in water splitting. Perovskite oxides (ABO3) with versatile structures and multiple physicochemical properties have triggered considerable interest in the OER. The leaching of A site cations can create nanostructures and amorphous motifs on the perovskite matrix, thus facilitating the OER process. However, selectively dissolving A site cations and simultaneously obtaining more active amorphous motifs derived from the B site cations remains a great challenge. Herein, a top‐down strategy is proposed to transform bulk crystalline perovskite (LaNiO3) into a nanostructured amorphous hydroxide by FeCl3 post‐treatment, resulting in an extremely low overpotential of 189 mV at 10 mA cm−2. The top‐down‐constructed amorphous catalyst with a large surface area has dual NiFe active sites, where high‐valence Ni3+‐based edge‐sharing octahedral frameworks are surrounded by interstitial distorted Fe octahedra and contribute to the superior OER performance. This top‐down strategy provides a valid way to design novel perovskite‐derived catalysts.

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In this work, a novel porous nanoneedlelike MnO-FeO catalyst (MnO-FeO nanoneedles) was developed for the first time by rationally heat-treating metal-organic frameworks including MnFe precursor synthesized by hydrothermal method. A counterpart catalyst (MnO-FeO nanoparticles) without porous nanoneedle structure was also prepared by a similar procedure for comparison. The two catalysts were systematically characterized by scanning and transmission electron microscopy, X-ray diffraction, thermogravimetric analysis, X-ray photoelectron spectroscopy, hydrogen temperature-programmed reduction, ammonia temperature-programmed desorption, and in situ diffuse reflectance infrared Fourier transform spectroscopy (in situ DRIFT), and their catalytic activities were evaluated by selective catalytic reduction (SCR) of NO by NH. The results showed that the rationally designed MnO-FeO nanoneedles presented outstanding low-temperature NH-SCR activity (100% NO conversion in a wide temperature window from 120 to 240 °C), high selectivity for N (nearly 100% N selectivity from 60 to 240 °C), and excellent water resistance and stability in comparison with the counterpart MnO-FeO nanoparticles. The reasons can be attributed not only to the unique porous nanoneedle structure but also to the uniform distribution of MnO and FeO. More importantly, the desired Mn/Mn and O/(O + O) ratios, as well as rich redox sites and abundant strong acid sites on the surface of the porous MnO-FeO nanoneedles, also contribute to these excellent performances. In situ DRIFT suggested that the NH-SCR of NO over MnO-FeO nanoneedles follows both Eley-Rideal and Langmuir-Hinshelwood mechanisms.

This review summarizes the various structural modifications and photovoltaic properties of the benzodithiophene–benzothiadiazole conjugated polymers [P(BDT–DTBT)] and their derivatives.