A high-performance supercapacitor electrode NiCo ₂ S ₄ (NCS) nanosheet on SiO ₂ @C core-shell nanospheres (SiO ₂ @C-NCS nanocomposite) is prepared via simple an effective solution-based method. Benefiting from compositional and structural advantages, the as-prepared SiO ₂ @C-NCS nanocomposite exhibits a high specific capacitance (625 F g ⁻¹ at 1 mA cm ⁻² ) and a stable cycling performance. An asymmetric supercapacitor (ASC) assembled with SiO ₂ @C-NCS nanocomposite as a positive electrode and carbon nanotube paper as a negative electrode in aqueous KOH solution demonstrated a high energy density of 16 Wh kg ⁻¹ at an ultra-high specific power of 7200 W kg ⁻¹ . These promising results suggest the possible application of mixed transition metal sulfides-based composites as advanced electrode materials for high-performance ASCs.

In this study, one-dimensional porous silicon nanowire (1D–PSiNW) arrays were fabricated by one-step metal-assisted chemical etching (MACE) to etch phosphorus-doped silicon wafers. The as-prepared mesoporous 1D–PSiNW arrays here had especially high specific surface areas of 323.47 m²·g⁻¹ and were applied as anodes to achieve fast charge–discharge performance for lithium ion batteries (LIBs). The 1D–PSiNWs anodes with feature size of ~7 nm exhibited reversible specific capacity of 2061.1 mAh·g⁻¹ after 1000 cycles at a high current density of 1.5 A·g⁻¹. Moreover, under the ultrafast charge–discharge current rate of 16.0 A·g⁻¹, the 1D–PSiNWs anodes still maintained 586.7 mAh·g⁻¹ capacity even after 5000 cycles. This nanoporous 1D–PSiNW with high surface area is a potential anode candidate for the ultrafast charge–discharge in LIBs with high specific capacity and superior cycling performance.

Metal ion capacitors have gained a lot of interest as a new kind of capacitor-battery hybrid energy storage system because of their high power density while maintaining energy density and a long lifetime.

Nickel sulfide (Ni₃S₂) has been widely known in the energy storage field, owing to the high theoretical capacitance, low cost, and environmental friendliness. We reported simple, low-cost hydrothermal synthesis of Ni₃S₂ nanoparticles as a remarkable electrode material for symmetric supercapacitor (SSC) in this paper. The structural characterization confirms the successful formation of the sample with a nanoparticle-like morphology with good crystallinity. The unique structure is composed of plenty of ion mobilization channels that exhibits superb electrochemical performance. When employed as an electrode material for supercapacitors, the fabricated Ni₃S₂ nanoparticles displayed the typical features of battery-type faradic electrodes showing an ultra-high specific capacitance of 2495 F g⁻¹ at 1 A g⁻¹ and excellent cycling stability (92.2% capacitance retention after 5000 consecutive CV cycles) within the potential frame of −0.2 to 0.6 V in a three-electrode system, which surpasses many previous literature reports. In the end, a SSC device was assembled exhibiting an optimized and stable potential window of 1.8 V with a high specific capacitance of 116.6 F g⁻¹ at 5 A g⁻¹. Moreover, the Ragone plot shows a high energy density of 52.4 W h kg⁻¹ and an ultra-high power density of 13 500.0 W kg⁻¹, indicating excellent cycling stability (95% retention after 7000 cycles). Additionally, we demonstrated a coin-type SSC that provides sufficient energy to turn on the red LED, which emits light over a certain period to open up possible realistic applications. These results show the great potential of Ni₃S₂ nanoparticles in the development of high-performance electrode materials for energy storage and conversion systems.

Due to their promising properties such as low corrosion resistance, excellent strength, high‐temperature operation, simple formability and machining, and, most importantly, cost‐effectiveness in the industry, honeycomb‐based heterostructures have been widely used as energy storage and conversion systems for decades. Despite their low density, honeycomb structures also have strong out‐of‐plane compression and shear properties, resulting in very high unique strengths. The honeycomb‐based molded structure, which was inspired by bee honeycombs and provides a material with low density and high out‐of‐plane compression and shear properties, has found widespread use and now plays a critical role in energy conversion and storage technologies such as lithium‐ion batteries, solar cells, and supercapacitors. These materials have a lot of promise in terms of addressing and environmental concerns regarding power sources at a time when global energy demand is skyrocketing. In light of this, we contend in this research paper that complex honeycomb‐based architectures outperform conventional simple 2D designs in a wide variety of technological applications. We also go into the different synthetic methods used to make honeycomb structures and look at how these novel materials may be used for long‐term electrochemical energy transfer and storage. Finally, the current challenges and opportunities for the construction of honeycomb systems are discussed, as well as new research directions.