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Enhancing the lifetime of perovskite solar cells (PSCs) is one of the essential challenges for their industrialization. Although the external encapsulation protects the perovskite device from the erosion of moisture and oxygen under various harsh conditions. However, the perovskite devices still undergo static and dynamic thermal stress during thermal and thermal cycling aging, respectively, resulting in irreversible damage to the morphology, component, and phase of stacked materials. Herein, the viscoelastic polymer polyvinyl butyral (PVB) material is designed onto the surface of perovskite films to form flexible interface encapsulation. After PVB interface encapsulation, the surface modulus of perovskite films decreases by nearly 50%, and the interface stress range under the dynamic temperature field (−40 to 85 °C) drops from −42.5 to 64.8 MPa to −14.8 to 5.0 MPa. Besides, PVB forms chemical interactions with FA+ cations and Pb2+, and the macroscopic residual stress is regulated and defects are reduced of the PVB encapsulated perovskite film. As a result, the optimized device's efficiency increases from 22.21% to 23.11%. Additionally, after 1500 h of thermal treatment (85 °C), 1000 h of damp heat test (85 °C & 85% RH), and 250 cycles of thermal cycling test (−40 to 85 °C), the devices maintain 92.6%, 85.8%, and 96.1% of their initial efficiencies, respectively. [ABSTRACT FROM AUTHOR]

The high energy density and low-cost O3-layered NaNi1/3Fe1/3Mn1/3O2 (NFM) is a representative layered cathode for sodium-ion batteries (SIBs). However, its long-term cycling stability needs further improvement and its high voltage usage is highly desired, which is quite challenging. The lack of full understanding of the cycling-induced failures hinders material optimization. Herein, we utilize advanced microanalysis techniques to comprehensively investigate the failure mechanisms of the O3-NFM layered cathode upon low-voltage (2.0–4.0 V) and high-voltage (2.0–4.3 V) cycling. We found that surface degradations play a dominant role during low-voltage cycling, and bulk failures become prominent upon high-voltage cycling. Surface cracking, corrosion, and structure transition together lead to slow charge transfer kinetics, resulting in chronic capacity decay. Bulk degradations such as intragranular cracking, void formation, and interlayer cation mixing severely deteriorate Na storage performance and Na diffusion kinetics, causing rapid capacity decay and voltage fading issues, which are the main challenges of the NFM layered cathode for high voltage usage. High charging cutoff voltage activates the cation migration and condensation, causing a highly disordered layered structure but no phase transition occurs in the bulk. Synergistically stabilizing the surface and bulk structure of the high-voltage O3-layered cathode is essential for achieving superior electrochemical performance. [ABSTRACT FROM AUTHOR]

The tailoring of active sites is closely related to the substrate. Dual‐atom catalysts (DACs) have been achieved on doped carbon, oxides, and 2D materials, but are rarely reported on metals, due to the challenges of sintering and alloying using metal as the host. Herein, an innovative approach to anchor isolated single atoms as dual‐atomic‐site alloy (DASA) through two‐step pyrolysis of porous structure is proposed. Firstly, the role of Zn and Co in generating pores during the pyrolysis of zeolite imidazolate framework (ZIFs) is revealed, and a hierarchical porous structure with self‐supported Co particles is achieved by the first‐step pyrolysis. Diffusion‐controlled reduction of precursors containing target metals is then allowed through hierarchical structures by second‐step pyrolysis, so to address the challenge of sintering and alloying at pyrolysis of high temperatures. The approach is demonstrated by synthesizing Ir1Ni1@Co/N‐C DASA, with outstanding bifunctional oxygen reduction/evolution reaction (ORR/OER) performance in both acidic and alkaline media, which is rarely reported. The density functional theory (DFT) calculations represent that adsorption‐free energies of intermediates OH and O are regulated to nearly 0 eV by Ir1 and Ni1 on Co. This work demonstrates a new path of constructing DASA using the designed porous structure, inspiring catalysts design in a related field. [ABSTRACT FROM AUTHOR]

Single-atom catalysts show excellent catalytic performance because of their coordination environments and electronic configurations. However, controllable regulation of single-atom permutations still faces challenges. Herein, we demonstrate that a polarization electric field regulates single atom permutations and forms periodic one-dimensional Au single-atom arrays on ferroelectric Bi4Ti3O12 nanosheets. The Au single-atom arrays greatly lower the Gibbs free energy for CO2 conversion via Au-O=C=O-Au dual-site adsorption compared to that for Au-O=C=O single-site adsorption on Au isolated single atoms. Additionally, the Au single-atom arrays suppress the depolarization of Bi4Ti3O12, so it maintains a stronger driving force for separation and transfer of photogenerated charges. Thus, Bi4Ti3O12 with Au single-atom arrays exhibit an efficient CO production rate of 34.15 µmol·g−1·h−1, ∼18 times higher than that of pristine Bi4Ti3O12. More importantly, the polarization electric field proves to be a general tactic for the syntheses of one-dimensional Pt, Ag, Fe, Co and Ni single-atom arrays on the Bi4Ti3O12 surface. The authors report a study preparing single atom (M = Pt, Ag, Fe, Co, and Ni) arrays on Au/Bi4Ti3O12 nanosheets using electric field polarization techniques. Photocatalytic CO2 reduction is shown to proceed effectively over Au/Bi4Ti3O12. [ABSTRACT FROM AUTHOR]

Cycling-induced cathode interfacial degradations are usually attributed to chemical process, while the physical effect is overlooked to a large extent. Herein, we investigate the failure mechanism of LiCoO2 cathode and reveal that misfit strain plays a dominant role in the surface layer exfoliation process. We illustrate that highly strained LiCoO2 surface can initiate massive surface cracks, leading to the LiCoO2 surface layer broken and exfoliation. Mechanical cracking coupled with chemical etching aggravates the surface layer degradation, leading to a weathering-like degradation on LiCoO2 surface. Our work reveals that interfacial degradation of electrode materials is a complex physicochemical process. Impact Statement We declare that we have no financial and personal relationships with other people or organizations. [ABSTRACT FROM AUTHOR]