Lithium-sulfur (Li-S) batteries depend on eco-friendly sulfur cathodes coupled with lithium metal anode that can attain ultra-high energy density. However, simultaneously inhibiting the shuttling effect, accelerating the redox kinetics and regulating Li⁺ uniform transport are critical for realizing the industrialization of Li-S batteries. Herein, a heterostructure construction and defect engineering synergistic strategy is put forward to synthesize the defect-rich Zn₂SnO_4−x/SnO_2−x heterostructure for both the sulfur cathode and lithium anode protection. Combined with theoretical calculations and experimental results, Zn₂SnO_4−x/SnO_2−x heterostructure with highly exposed active sites can realize high-efficient electron transfer and decreased reaction energy barriers, promoting the multi-phase catalytic conversion of lithium polysulfides. Meanwhile, the Zn₂SnO_4−x/SnO_2−x modified separator modulates the uniform Li⁺ distribution, thus suppressing dendrite growth at the anode region. As a result, the Li-S full battery based on Zn₂SnO_4−x/SnO_2−x exhibits good feedback in terms of cycling stability (787 mAh·g⁻¹ after 200 cycles at 0.2 C) at a high sulfur loading of 3.0 mg·cm⁻².

The photocatalytic degradation of plastic waste represents a pivotal strategy for mitigating the global plastic pollution and fostering resource-efficient utilization. Herein, a facile impregnation method was used to uniformly load various Ni-substituted polyoxometalates (Ni-POMs) onto CdS nanospheres and thus obtain a series of single-cluster Ni-POM@CdS photocatalysts. During visible-light irradiation for 10 h, the catalyst with the highest synergistic photoredox performance (Ni₉@CdS-10) achieved an exceptional extent of polylactic acid degradation and H₂ productivity (22.29 mmol·g_cat⁻¹) exceeding that of pristine CdS ~ 160-fold. The generation of pyruvate—a versatile and valuable chemical—as a degradation product (19.01 mmol·g_cat⁻¹) rendered the process highly economically viable. Systematic control experiments and comprehensive characterization analyses indicate that the photocatalytic degradation of plastic waste by Ni₉@CdS-10 proceeds via a charge transfer–mediated mechanism, with the Ni₉ clusters acting as electron sponges and efficiently extracting photogenerated electrons from CdS to promote H₂ evolution while facilitating hole-dominated plastic oxidation. This work provides valuable insights into the development of plastic waste degradation processes promoted by Ni-POM photocatalysts and establishes a practical strategy for converting plastic waste into fuels and chemicals.

Alkali-water electrolyzers and hydroxide exchange membrane fuel cells are emerging as promising technologies to realize hydrogen economy. Developing cost-effective electrode materials with high activities towards corresponding hydrogen evolution (HER) and oxidation (HOR) reactions plays a crucial role in commercial hydrogen production and utilization. Herein, we fabricated a V-doped Ni₃N/Ni heterostructure (V-Ni₃N/Ni) through a controlled nitridation treatment on a V-incorporated nickel hydroxide precursor. The resultant catalyst exhibits comparable catalytic activity and durability to commercial Pt/C in terms of both HER (a low overpotential of 44 mV at the current density of 10 mA·cm^-2) and HOR (a high current density of 1.54 mA·cm^-2 at 0.1 V versus reversible hydrogen electrode) under alkaline conditions. The superior activity of V-Ni₃N/Ni grown on different substrates further implies its intrinsic performance. Density functional theory (DFT) calculations reveal that the coupled metallic Ni and doped V can promote the water adsorption, accelerate the Volmer step of alkaline HER, as well as optimize the adsorption and desorption of hydrogen intermediate (H^*) to reach a balanced ΔG_H* value.

The high energy density of lithium-sulfur batteries (LSBs) is mainly based on the complex redox reactions and phase conversions. The sluggish redox kinetics and the large accumulation of soluble polysulfides in the electrolyte leads to low sulfur utilization and serious shuttle effect. Herein, an integrated sulfur cathode is constructed through a facile and large-scale method. It is composed of sulfur-N, S doped bamboo like CNTs@Co₃S₄ (NSC@Co₃S₄) composites on polypropylene separator. The immobilized polysulfides on the NSC@Co₃S₄ surface are further reduced/oxidized during the discharge/charge process via the efficient bi-functional catalytic effect of NSC@Co₃S₄, resulting in the rapid conversion of LiPSs. Consequently, the integrated sulfur cathode delivers a high initial reversible capacity of 1, 473.6 mAh·g^-1 at 0.2 C and a high specific capacity of 979 mAh·g^-1 at 1 C after 500 cycles as well as excellent cycling stability for 1, 000 cycles with a high specific capacity of 362.5 mAh·g^-1 at 5 C, which are superior to reported similar host materials.