Achieving both a low operating temperature for photovoltaic (PV) and a high heat collection temperature for photothermal (PT) conversion in full-spectrum solar energy utilization is challenging with traditional spectrum-splitting methods. Therefore, this study focuses on the full-spectrum solar utilization and proposes a novel multi-stage concentrating and spectrum-splitting coupling approach for complementary photovoltaic-thermophotovoltaic (PV-TPV) conversion. Multi-stage thermophysical models are developed based on thermodynamic analysis, Shockley-Queisser model coupling, and external quantum efficiency model coupling, incorporating cell combinations with different bandgaps and temperature coefficients, enabling performance analysis from idealized scenarios to realistic conditions. A single-stage spectrum splitting PV-TPV system is optimized as a baseline, and the impact of multi-stage spectrum coupling on system performance is investigated. Results show that low-bandgap cells with higher temperature coefficients can achieve superior performance at lower concentration ratios compared with high-bandgap cells at higher concentration ratios. Considering the practical external quantum efficiency (EQE) model, low-bandgap cells demonstrate additional advantages, achieving a maximum system efficiency of 41.82% at C₁ = 500 and C₂ = 300. The multi-stage spectrum-splitting design allows decoupling of the spectrum and concentration ratio, effectively reducing the system concentration ratio by more than 50% while maintaining high system performance. This not only facilitates device design and practical implementation but also enhances theoretical efficiency, demonstrating significant application potential. The study provides valuable insights for the development of full-spectrum PV-TPV conversion methods.

Aqueous zinc-ion batteries (AZIBs) have emerged as promising candidates for large-scale energy storage systems in the post-lithium era, owing to their inherent safety and cost-effectiveness. However, their practical implementation faces significant challenges, including chemical corrosion, uncontrolled dendrite formation, and hydrogen evolution reactions (HER). To address these limitations, an innovative “hydrophobic-zincophilic” Pd/g-C₃N₄ composite coating was developed for Zn anodes by atomic-layer-deposition (ALD). The g-C₃N₄ matrix serves as an ion flux regulator, while uniformly dispersed Pd nanoparticles function as zincophilic nucleation sites, enabling homogeneous Zn deposition. In situ optical characterization demonstrates the coating’s dual functionality: the hydrophobic component effectively minimizes water contact, while the zincophilic phase guides ordered Zn plating, jointly suppressing parasitic reactions. The modified Pd/g-C₃N₄@Zn anode achieves exceptional cycling stability (> 2500 h) and maintains a remarkable Coulombic efficiency of 99.56% over 5000 cycles at 2 A/g, representing a significant advancement in AZIB anode engineering. This work provides a generalizable interfacial design strategy for developing high-performance AZIB systems.