Direct ethanol fuel cells (DEFCs) have drawn attention for their simplicity, rapid start-up, high power density and environmental friendliness. Despite these advantages, the widespread application of DEFCs faces challenges, primarily due to the inadequate performance of anode and cathode catalysts. Pd-based materials have shown exceptional catalytic activity for both the ethanol oxidation reaction (EOR) and the oxygen reduction reaction (ORR). Alloying noble metals with rare earth elements has emerged as an effective strategy to further enhance the catalytic activity by modulating the electronic structure. In this study, we synthesized a series of palladium-rare earth (Pd₃RE) alloys supported on carbon to serve as bifunctional catalysts that efficiently promote both ORR and EOR. Compared to Pd/C, the Pd₃Tb/C catalyst exhibits 3.1-fold and 1.8-fold enhancement in activity for ORR and EOR, respectively. The charge transfer in the Pd₃Tb/C results in an electron-rich Pd component, thereby weakening the binding energy with oxygen species and facilitating the two reactions.

Currently, dual atomic catalysts (DACs) with neighboring active sites for oxygen reduction reaction (ORR) still meet lots of challenges in the synthesis, especially the construction of atomic pairs of elements from different blocks of the periodic table. Herein, a “rare earth (Ce)-metalloid (Se)” non-bonding heteronuclear diatomic electrocatalyst has been constructed for ORR by rational coordination and carbon support defect engineering. Encouraging, the optimized Ce-Se diatomic catalysts (Ce-Se DAs/NC) displayed a half-wave potential of 0.886 V vs. reversible hydrogen electrode (RHE) and excellent stability, which surpass those of separate Ce or Se single atoms and most single/dual atomic catalysts ever reported. In addition, a primary zinc-air battery constructed using Ce-Se DAs/NC delivers a higher peak power density (209.2 mW·cm⁻²) and specific capacity (786.4 mAh·g_Zn⁻¹) than state-of-the-art noble metal catalysts Pt/C. Theoretical calculations reveal that the Ce-Se DAs/NC has improved the electroactivity of the Ce-N₄ region due to the electron transfer towards the nearby Se specific activity (SA) sites. Meanwhile, the more electron-rich Se sites promote the adsorptions of key intermediates, which results in the optimal performances of ORR on Ce-Se DAs/NC. This work provides new perspectives on electronic structure modulations via non-bonded long-range coordination micro-environment engineering in DACs for efficient electrocatalysis.

Rare-earth (RE) halide solid electrolytes (HSEs) have been an emerging research area due to their good electrochemical and mechanical properties for all-solid-state lithium batteries (ASSBs). However, only very limited types of HSEs have been reported with high performance. In this work, tens of grams of RE-HSE Li₃TbBr₆ (LTbB) was synthesized by a vacuum evaporation-assisted method. The as-prepared LTbB displays a high ionic conductivity of 1.7 mS·cm⁻¹, a wide electrochemical window, and good formability. Accordingly, the assembled solid lithium-tellurium (Li-Te) battery based on the LTbB HSE exhibits excellent cycling stability up to 600 cycles, which is superior to most previous reports. The processes and the chemicals during the discharge/charge of Li-Te batteries have been studied by various in situ and ex situ characterizations. Theoretical calculations have demonstrated the dominant conductivity contributions of the direct [octahedral]–[octahedral] ([Oct]–[Oct]) pathway for Li ion migrations in the electrolyte. The Tb sites guarantee efficient electron transfer while the Li 2s orbitals are not affected during migration, leading to a low activation barrier. Therefore, this successful fabrication and application of LTbB have offered a highly competitive solution for solid electrolytes in ASSBs, indicating the great potential of RE-based HSEs in energy devices.

Currently, single-atom combo catalysts (SACCs) for carbon dioxide reduction reaction (CO₂RR) to the formation of HCOOH are still very limited, especially the lanthanide-based SACCs. In this work, the novel SACCs with atomically dispersed In and Ce active sites were successfully prepared on the nitrogen-doped carbon matrix (InCe/CN). Both aberration-corrected high-angle annular dark-field scanning transmission electron microscopy (AC-HAADF-STEM) images and the extended X-ray absorption fine structure (EXAFS) spectra proved the well-isolated In and Ce atoms. The as-prepared InCe/CN shows a high Faradaic efficiency (FE) (77%) and current density of HCOOH formation (j_HCOOH) at −1.35 V vs. reversible hydrogen electrode (RHE), much higher than the single atom catalysts. Theoretical calculations have indicated that the introduced Ce single atom sites not only significantly promote electron transfer but also optimize the In-5p orbitals towards higher selectivity towards the HCOOH formation. This work innovatively extends the design of SACCs towards the main group and Ln metals for more applications.

Controlled synthesis of transition metal dichalcogenide (TMD) monolayers with unusual crystal phases has attracted increasing attention due to their promising applications in electrocatalysis. However, the facile and large-scale preparation of TMD monolayers with high-concentration unusual crystal phase still remains a challenge. Herein, we report the synthesis of MoX₂ (X = Se or S) monolayers with high-concentration semimetallic 1Tx phase by using the 4H/face-centered cubic (fcc)-Au nanorod as template to form the 4H/fcc-Au@MoX₂ nanocomposite. The concentrations of 1Tx phase in the prepared MoSe₂ and MoS₂ monolayers are up to 86% and 81%, respectively. As a proof-of-concept application, the obtained Au@MoS₂ nanocomposite is used for the electrocatalytic hydrogen evolution reaction (HER) in acid medium, exhibiting excellent performance with a low overpotential of 178 mV at the current density of 10 mA/cm², a small Tafel slope of 43.3 mV/dec, and excellent HER stability. This work paves a way for direct synthesis of TMD monolayers with high-concentration of unusual crystal phase for the electrocatalytic application.

Developing a reliable system to efficiently and safely deliver peptide drugs into tumor tissues still remains a great challenge since the instability of peptide drugs and low ability to traverse the cell membrane. Herein, we constructed a multifunctional nanoplatform based on porous europium/gadolinium (Eu/Gd)-doped NaLa(MoO₄)₂ nanoparticles (NLM NPs) to deliver antitumor peptide of B-cell lymphoma/leukemia-2-like protein 11 (BIM) for cancer therapy. The porous NLM NPs exhibited inherent photoluminescent, magnetic and X-ray absorbable properties, which enable them for triple-modal bioimaging, including fluorescence, magnetic resonance imaging (MRI) and computed tomography (CT). This triple-modal bioimaging can contribute to monitoring NLM NPs biodistribution and guiding therapy in vitro and in vivo. Furthermore, the NLM NPs showed negligible cytotoxicity in vitro and tissue toxicity in vivo. Importantly, NLM NPs could load the antitumor peptide of BIM and efficiently improve the resistance of peptide drugs to proteolysis. The BIM peptide was efficiently delivered into the tumor cells by NLM NPs, which can inhibit the growth and promote the apoptosis of cancer cells in vitro, significantly inhibit the tumor growth in vivo. Notably, NLM-BIM theranostic nanoplatform exhibits low systemic toxicity and fewer side effects in vivo. The NLM NPs can serve as a promising multifunctional peptide delivery nanoplatform for multi-modal bioimaging and cancer therapy.