ZnO/Ni₃ZnC_0.7/x% CNT (x = 0, 2, 5, 10) urchin-like structures have been synthesized using a facile method based on metal-organic frameworks (MOFs) and applied as the electromagnetic absorber. The results of the experiments demonstrate that the content of multi-wall carbon nanotubes (MWCNT) has a great influence on the absorbing performance of the hybrid material. Conduction loss, interfacial polarization and ferromagnetic resonance all contribute to the electromagnetic absorption. The urchin-like ZnO/Ni₃ZnC_0.7/5% CNT composite presents excellent absorbing properties. When the filler loading of ZnO/Ni₃ZnC_0.7/5% CNT composite in paraffin matrix is only 10 wt.%, a minimum reflection loss of −33.2 dB is achieved at a layer thickness of 4.9 mm.

Photocatalysis is a green technique that can convert solar energy to chemical energy, especially in H₂ production from water splitting. In this study, ZnO and red phosphorus (ZnO/RP) heterostructures were fabricated through a facile calcination method for the first time, which showed the considerable photocatalytic activity of H₂ evolution. The photocatalytic activities of heterostructures with different ratios of RP have been investigated in detail. Compared to bare ZnO, ZnO/RP heterostructures exhibit a 20.8-fold enhancement for H₂ production and furthermore overcome the photocorrosion issue of ZnO. The improved photocatalytic activities highly depend on the synergistic effect of the high migration efficiency of photo-induced electron–hole pairs with the inhibited charge carrier recombination on the surface. The presented strategy can also be applied to other semiconductors for various optoelectronics applications.

Novel fibrous graphitic carbon nitride (g-C₃N₄) derivatives prepared from metal organic frameworks (MOFs) were doped with Ce³⁺ (Ce-C₃N₄) as photocatalytic materials. Ce-C₃N₄ was characterized using various techniques, revealing its high specific surface area, excellent photocatalytic activity, and stability for H₂ evolution under visible light irradiation. The fluorine modified samples show superior photocatalytic activity under visible light irradiation, which is due to the presence of more active sites and enhanced absorption of solar energy. This work provides a new synthetic route for MOF-derived g-C₃N₄ that can be doped with different metal ions. The fluorine modified Ce-C₃N₄ is an efficient photocatalyst with potential for many applications related to energy and the environment.

Interfacial solar water evaporation has emerged as an effective technique for converting solar energy to thermal energy, which can then be applied to clean water production and sewage treatment. This review discusses the primary characterization techniques used to evaluate the key aspects of interfacial solar water evaporators: the intrinsic and performance evaluation. Each technique is discussed with a brief explanation of its foundations, followed by carefully selected examples. This review is aimed at assisting materials chemists and physicists, particularly students, in choosing the most appropriate techniques for characterizing photothermal materials.

An effective strategy for significantly enhancing photocatalytic activity of composite materials is to construct heterojunctions. Herein, a series of imidazole-modified heterostructured g-C₃N₄/SnO (CNIS) Z-scheme photocatalysts were prepared by calcination methods, leading to superior photocatalytic performance than pure SnO and imidazole-modified g-C₃N₄. Rhodamine B (Rh B) aqueous solution was taken as the target pollutant, and the result presented that both imidazole modification and the Z-scheme heterojunction construction benefited from significant enhancement in photocatalytic activity. Moreover, it is revealed that electrons were transferred from imidazole-modified g-C₃N₄ to SnO through the interface of the composite by XPS analysis. Under visible light (>420 nm) irradiation, the built-in electric field, band edge bending, and Coulomb interaction work synergistically to drive the recombination of relatively useless electrons and holes in the hybrid. As a result, the residual electrons and holes, which possess enhanced reducibility and oxidizability, endow the composite with exceptional redox capability. This research can not only deepen our comprehension of designing and fabricating innovative Z-scheme heterojunction photocatalysts but also presents an effective approach to tackle environmental pollution issues in the future.