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Here we report an Ag-modified Cu/CuO (Cu/CuO–Ag) catalyst with a porous 3D structure, which can efficiently electrochemically reduce CO2 to ethylene and other C2+ products.

In this study, microstructural evolution and strengthening of commercial purity Ti (CP-Ti)/Ti–0.4Ni graded material (GM) fabricated by laser melting deposition (LMD) is elucidated. Compared with the coarse α-grains of CP-Ti, fine α-lath and Ti2Ni phase was obtained in Ti–0.4Ni in LMD CP-Ti/Ti–0.4Ni GM. Precipitation strengthening and microstructural refining led to significant increase in strength from ~ 479 MPa for CP-Ti to ~ 882 MPa for Ti–0.4 Ni. The CP-Ti/Ti–0.4Ni GM was combined at the atomic level such that the interface of coarse-α grains and α-lath shared identical parent β-Ti grain. Microalloying with Ni in the GM avoided issues of composition reapportionment and deterioration of mechanical properties at the interface of GM. This study underscores that microalloyed Ti–0.4Ni has the potential to provide high-performance graded material by LMD.

As a new two-dimensional material, MXene has attracted extensive attention because of its unique structure and electrochemical properties. MXene-based self-supporting films have been widely studied due to their flexibility, light weight and lack of need for adhesives and conductive agents. In the present work, we used facile ultrasonic and annealing methods to fabricate MnO2/MXene–Ti3C2Tx foam hybrids for lithium storage. In the hybrid material, MnO2 nanoparticles expand the MXene lamellar spacing, provide tunnels for lithium ion shuttling and accelerate the transport speed of lithium ions, thus improving the rate performance of the electrode materials. The existence of the MXene nanosheets can release the internal stress due to the volume expansion of MnO2 during charging/discharging, reduce the electrode resistivity and improve the cycling stability of materials. The initial discharge capacity can reach 1203 mA h g−1 and the capacity can be maintained at about 600 mA h g−1 after 200 cycles. Moreover, the capacity of the electrode attenuates less at a large current and the capacity is about 350 mA h g−1 at 5 A g−1.

The application of silicon-based anode remains a serious challenge due to its intrinsic volumetric expansion effect and low conductivity. In our work, a novel CNT-interspersed hierarchical carbon shell structure (denoted as PDA@CoZn-NC@Si) is synthesized by wrapping Si uniformly in the bimetallic zeolite imidazolate frameworks (ZIFs) and then encapsulated with a dopamine-derived carbon shell. The PDA@CoZn-NC@Si anode delivers better cycle stability of 814 mAh/g at 0.5C for 400 cycles (only −0.14% capacity reduction per cycle) and possesses excellent rate capability, which benefits from the inner porous buffer spaces, interspersed CNT, and solid heterogeneous carbon shells. In addition, the full cell is assembled by pairing a solution-based chemically prelithiated PDA@CoZn-NC@Si anode with a Li(Ni1/3Co1/3Mn1/3)O2 (NCM111) cathode, and it presents an improved initial coulombic efficiency (88.3%) and a high energy density (419.8 Wh/kg). This study provides effective guidance for optimizing the microstructure design and prelithium of Si-based anodes.