Li-CO2 batteries are widely studied as a promising technology for greenhouse-gas CO2 fixation as well as for energy conversion and storage devices. Their further development, however, is hindered by the refractory discharge products, leading to large polarization voltage and low round-trip efficiency. Here, W2C nanoparticles embedded in the walls of carbon nanotubes (W2C-CNTs) are prepared successfully. An efficient Li-CO2 battery with a W2C-CNTs cathode displays ultralow charge voltage (3.2 V) and high round-trip efficiency (90.1%). The low polarization comes from electron-rich W atoms that break the stable triangle of CO3 2– via W–O bonds. The resulting amorphous discharge products could be readily and reversibly decomposed during charging. Raman and XAS spectra provide direct and solid evidence for the W–O bonds. Also, DFT calculations show there is electron transfer between the W2C surface and Li2CO3, resulting in a low decomposition barrier for Li2CO3 on the W2C substrate.

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Subnanometric metal clusters have attracted extensive attention because of their unique properties as heterogeneous catalysts. However, it is challenging to obtain uniformly distributed metal clusters under synthesis and reaction conditions. Herein, we report a template‐guidance protocol to synthesize subnanometric metal clusters uniformly encapsulated in beta‐zeolite, with the metal ions anchored to the internal channels of the zeolite template via electrostatic interactions. Pt metal clusters with a narrow size range of 0.89 to 1.22 nm have been obtained on the intersectional sites of beta‐zeolite (Pt@beta) with a broad range of Si/Al molar ratios (15–200). The uniformly distributed Pt clusters in Pt@H‐beta are subject to strong electron withdrawal by the zeolite, which promotes transfer of active hydrogen, providing excellent activity and stability in hydrodeoxygenation reactions. A general strategy is thus proposed for the encapsulation of subnanometric metal clusters in zeolites with high thermal stability.

Doping in carbon anodes can introduce active sites, usually leading to extra capacity in Li-ion batteries (LIBs), but the underlying reasons have not been uncovered deeply. Herein, the dodecahedral carbon framework (N-DF) with a low nitrogen content (3.06 wt %) is fabricated as the anode material for LIBs, which shows an extra value of 298 mA h g –1 during 250 cycles at 0.1 A g –1 . Various characterizations and theoretical calculations demonstrate that the essence of the extra capacity mainly stems from non-coplanar sp 2 /sp 3 hybridized orbital controlling non-Euclidean geometrical structure, which acts as new Li-ion active sites toward the excess Li + adsorption. The electrochemical kinetics and in situ transmission electron microscope further reveal that the positive and negative curvature architectures not only provide supernumerary Li + storage sites on the surface but also hold an enhanced (002) spacing for fast Li + transport. The sp 2 /sp 3 hybridized orbital design concept will help to develop advanced electrode materials.