Photocatalysis has emerged as a promising method for industrial sewage elimination. The main bottleneck of this process is the development of an efficient, stable, and cost-effective catalyst that can oxidize pollution under visible light. Herein, surface disorders and Bi nanoparticles are successfully introduced into BiOCl_xI_1−x nanosheets using low-cost NaBH₄ as a reductant in a liquid-phase environment. Benefiting from the enhanced charge separation, transfer, and donor density resulting from the formation of surface disorders, and Bi deposition as cocatalyst, the photocatalytic performance of the reductive BiOCl_xI_1−x nanosheets is fivefold higher than that of the untreated BiOCl_xI_1−x nanosheets for phenol degradation under visible light irradiation. Additionally, the reductive BiOCl_xI_1−x nanosheets have a superior stability after five cycles.

A facile fabrication route towards a titanium-modified hematite photoanode has been developed, and the photoelectrochemical properties of this anode have been evaluated. Compared to pristine hematite, the activity of the modified photoanode in this work delivered almost twofold higher photocurrent under Air Mass 1.5G illumination. Further research revealed that the enhanced performance of the hematite photoanode with a titanium-modified surface resulted from the dominant impact of heterojunction formation and suppressed surface recombination, supplemented by a slightly improved light-harnessing ability.

BiVO₄ is one of the most promising candidates for photoanodes in solar water splitting. However, the poor charge-separation yield in BiVO₄ has limited its photochemical activity. Here, we overcome this limitation by constructing a nanoporous morphology that effectively inhibits bulk carrier recombination as well as undergoes controlled introduction of oxygen vacancies through hydrogenation. In comparison to pristine BiVO₄, hydrogen-treated BiVO₄ (H-BiVO_4−x) exhibits a superior photocurrent and electron-hole separation yield, owing to enhanced carrier density and conductivity. In addition, we adopt a layer of nickel–borate (Ni–B_i) complex on the H-BiVO_4−x surface as an oxygen evolution catalyst to improve the water oxidation kinetics. The Ni–B_i/H-BiVO_4−x photoanode results in a large cathodic shift (350 mV) in the onset potential for water oxidation at pH 9. Moreover, the photoanodes exhibit high performance in the low-bias regime and achieve a maximum power point of 0.82 % (photon-to-current efficiency) for solar water oxidation at potentials as low as 0.79 V versus RHE with a photocurrent of 2.26 mA cm⁻². We attribute these improved photoelectrochemical performances to the enhanced charge separation, higher carrier density, better conductivity of H-BiVO_4−x, and the role of Ni–B_i as a hole conductor, facilitating photogenerated electron mobilization.

After long electrochemical cycles, the continuous loss in the capacity of nickel oxide (NiO) hinders its practical application as anode material for lithium-ion batteries. The need to improve the lithium-storage performance of NiO becomes essential for the accomplishment of high-performance lithium-ion batteries. In this respect, a new form of 3D NiO, which comprises TiO₂ nanoparticles, has been fabricated and used as anode for lithium-ion storage. The as-prepared 3D NiO–TiO₂ nanocomposites achieved areal discharge capacities of 1.49 and 0.78 mAh cm⁻² at current densities of 1.0 and 6.0 mA cm⁻², respectively. The improvement in the lithium-storage properties of the NiO/TiO₂ nanocomposite is attributed to the TiO₂ nanoparticles creating rational interfaces with the NiO, which incredibly supports the NiO surface and improves the structural stability.

Flexible energy-storage devices are attracting increasing attention as they show unique promising advantages, such as flexibility, shape diversity, light weight, and so on; these properties enable applications in portable, flexible, and even wearable electronic devices, including soft electronic products, roll-up displays, and wearable devices. Consequently, considerable effort has been made in recent years to fulfill the requirements of future flexible energy-storage devices, and much progress has been witnessed. This review describes the most recent advances in flexible energy-storage devices, including flexible lithium-ion batteries and flexible supercapacitors. The latest successful examples in flexible lithium-ion batteries and their technological innovations and challenges are reviewed first. This is followed by a detailed overview of the recent progress in flexible supercapacitors based on carbon materials and a number of composites and flexible micro-supercapacitors. Some of the latest achievements regarding interesting integrated energy-storage systems are also reviewed. Further research direction is also proposed to surpass existing technological bottle-necks and realize idealized flexible energy-storage devices.

Bimetallic core-shell nanostructures are emerging as more important materials than monometallic nanostructures, and have much more interesting potential applications in various fields, including catalysis and electronics. In this work, we demonstrate the facile synthesis of core-shell nanotube array catalysts consisting of Pt thin layers as the shells and Ni nanotubes as the cores. The porous Ni@Pt core-shell nanotube arrays were fabricated by ZnO nanorod-array template-assisted electrodeposition, and they represent a new class of nanostructures with a high electrochemically active surface area of 50.08 m² (g Pt)⁻¹, which is close to the value of 59.44 m² (g Pt)⁻¹ for commercial Pt/C catalysts. The porous Ni@Pt core-shell nanotube arrays also show markedly enhanced electrocatalytic activity and stability for methanol oxidation compared with the commercial Pt/C catalysts. The attractive performances exhibited by these prepared porous Ni@Pt core-shell nanotube arrays make them promising candidates as future high-performance catalysts for methanol electrooxidation. The facile method described herein is suitable for large-scale, low-cost production, and significantly lowers the Pt loading, and thus, the cost of the catalysts.

Herein Ce_1−xFe_xO_2−δ nanocomposites were investigated for dilute magnetic semiconductor (DMS) properties. Ce_1−xFe_xO_2−δ nanospheres and porous nanostructures with high surface areas have been successfully prepared by electrochemical deposition at room temperature and atmospheric pressure. The structures and morphologies of Ce_1−xFe_xO_2−δ deposits were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and N₂ adsorption–desorption techniques. The magnetic properties of the prepared Ce_1−xFe_xO_2−δ nanospheres and porous nanostructures were studied, and they showed room-temperature ferromagnetism and giant magnetic moments. In addition, the effects of morphologies and compositions on the magnetic properties of Ce_1−xFe_xO_2−δ deposits were studied.