Layered double hydroxides (LDHs) are ionic layered compounds characterized by anion-containing intermediate regions within positively charged brucite-like layers. LDHs have shown high electrochemical activity in energy conversion systems such as batteries and fuel cells. In this study, we developed a hierarchically porous nanostructure derived from zeolitic imidazolate framework-67, which was subsequently transformed into an LDH structure with varying Ni concentrations. We precisely controlled the Ni-to-Co ratio within the LDH structure and investigated how different mole fractions of Co and Ni influence catalytic activity and selectivity for the electrochemical urea oxidation reaction (UOR). LDH structures with low Ni content (up to 40%) demonstrated high activity and selectivity for O 2 due to their structural instability and the predominant oxygen evolution reaction (OER) originating from ZIF-67. In contrast, LDHs with high Ni content (over 60%) supressed OER and exhibited enhanced activity for UOR. The resulting hollow structure with an expanded electrochemically active surface in LDHs with high Ni content could improve mass transport and diffusion at the electrode interface, leading to better reaction kinetics and higher current densities. These findings provide a foundational design guideline for metal–organic framework-derived nanostructure in UOR.

Perovskite solar cells (PSCs) have attracted considerable attention in the field of photovoltaics owing to their high power conversion efficiency (PCE), cost-effective production methods, and versatile applications. However, the widespread use of lead (Pb)-based materials in PSCs poses challenges related to their toxicity and environmental sustainability. This review explores recent advances in the development of Pb-free perovskite materials, such as tin (Sn)-based, germanium (Ge)-based, and other B(IV) and B(III) cation alternatives, while assessing their electronic properties, stability, and performance-enhancing strategies. Additionally, we discuss the use of green solvents and fabrication techniques to minimize their environmental impact. This review aims to guide future research toward safe, efficient, and environmentally sustainable PSC technologies, ensuring that the benefits of solar energy can be harnessed without compromising human health or the environment.

Wearable photothermal materials can capture light energy in nature and convert it into heat energy, which is critical for flexible outdoor sports. However, the conventional flexible photothermal membranes with low specific surface area restrict the maximum photothermal capability, and loose structure of electrospun membrane limits durability of wearable materials. Here, an ultrathin nanostructure candle soot/ multi-walled carbon nanotubes / poly (l-lactic acid) (CS/MWCNTs/PLLA) photothermal membrane is first prepared via solvent-induced recrystallization. The white blood cell membrane-like nanowrinkles with high specific surface area are achieved for the first time and exhibit optimal light absorption. The solvent-induced recrystallization also enables the membrane to realize large strength and durability. Meanwhile, the membranes also show two-sided heterochromatic features and transparency in thick and thin situations, respectively, suggesting outstanding fashionability. Nanowrinkled photothermal membranes by novel solvent-induced recrystallization show high flexibility, fashionability, strength, and photothermal characteristics, which have huge potential for outdoor warmth.