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To address the challenges of high error rates and poor generalization in current deep learning models for predicting lattice thermal conductivity (LTC), we introduce CrysGraphFormer, an innovative equivariant crystal graph transformer model tailored for this task. The model incorporates an improved multi-head self-attention mechanism and human-designed feature descriptors. By utilizing a message-passing mechanism to update node information, it introduces relative coordinate differences to represent crystal symmetry, avoiding the traditionally used complex and computationally expensive higher-order representations. We constructed a comprehensive dataset containing 5729 LTC data points (300 K), including 5477 materials from AFLOW, 112 MAX and MAB phase materials calculated using VASP, and 140 for half-Heusler alloys. Experimental results demonstrate that the CrysGraphFormer model achieves state-of-the-art performance in LTC prediction tasks and excels in predicting fundamental properties. The model offers good interpretability, providing insights from chemical and materials science perspectives. Furthermore, we validated the model's application potential in the field of thermoelectric materials by predicting the LTC of 59 thermoelectric materials and 55 ternary semiconductor materials, with results consistent with DFT calculations. Finally, the uncertainty of CrysGraphFormer was assessed using the Monte Carlo Dropout method. [ABSTRACT FROM AUTHOR]

The development of modern information technology has recently put forward higher requirements for the ingenious design of electromagnetic wave absorbing (EMA) materials with a broad bandwidth at a low filling ratio. Herein, three-dimensional (3D) S-doped Co3O4 microflowers@reduced graphene oxide (S-Co3O4@RGO) aerogels are successfully prepared by interface and defect engineering with superior EMA capability. The 3D structure with a high surface-to-volume ratio can effectively avoid the agglomeration of Co3O4 and enhance the RGO–Co3O4 heterointerfaces to implement multiple reflection mechanisms. The synergistic effect of atom and phase cross-hybridization can improve defect-induced polarization centres and coherent interface-induced interface polarization. Meanwhile, the defects located at the interface have more charge transfer to enhance interface polarization than that at the interior, which is first proposed and demonstrated by density functional theory (DFT) calculations. Thus, the minimal reflection loss value can reach −56.7 dB (3.6 mm, 5.44 GHz) and the maximum effective absorption bandwidth is 8.48 GHz (ranging from 9.28 to 17.76 GHz) at a matching thickness of 2.3 mm with a filling ratio of 5 wt%. This work opens a new pathway to synthesize electromagnetic wave absorbents with synergistic defect and interface induced polarization loss, and has tremendous potential for EMA applications. [ABSTRACT FROM AUTHOR]

The Ag–Cu2O/PANI composite material was synthesized using a simple, fast, and low-cost process, which is attractive for its many applications in the fields of photocatalysis, surface enhanced Raman scattering (SERS), and characterization. SEM, TEM, XRD, FT-IR, TG, UV-Vis and XPS measurements confirmed the successful synthesis of the Ag–Cu2O/PANI composite material. First-principles calculations on the basis of density functional theory (DFT) were used to analyze regulation of the work function of Cu2O. The results showed that Ag–Cu2O/PANI had an extremely high stability when exposed to oxygen, water, and light for a long period of time, which was attributed to the physical coating of Ag nanoparticles (Ag NPs) transferring the electrons (e−) and holes (h+) inside the Cu2O to the surface through the Schottky barrier to prevent photocorrosion. The deposition of Ag NPs also increased the intensity and time of the oxidative stress reaction of Cu2O, as evidenced by the reactive oxygen species (ROS) test. Ag NPs distributed on the surface of Cu2O particles formed many ion release channels, resulting in an excellent sustained release of Cu2+ ions. PANI as a protective barrier prevented Cu2O from directly contacting the external solution and releasing Cu2+ ions. PANI had an excellent e− transfer ability as a conductive polymer, which improved the efficiency of photogenerated e− and h+ separation of Cu2O. Our results showed that the Ag–Cu2O/PANI exhibited a high long-term antibacterial activity against S. aureus and P. aeruginosa, bacterial inhibition rates of which were maintained around 78% and 80% after being stored in phosphate buffer saline solution for 30 days. In this paper, Ag–Cu2O/PANI is proposed which can enhance the photocatalytic performance of Cu2O and long-term antibacterial activity. [ABSTRACT FROM AUTHOR]