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We have performed ab-initio band structure calculations on more than two thousand half-Heusler compounds in order to search for new candidates for topological insulators.Herein, LiAuS and NaAuS are found to be the strongest topological insulators with the bulk band gap of 0.20 and 0.19 eV, respectively, different from the zero band gap feature reported in other Heusler topological insulators. Due to the inversion asymmetry of the Heusler structure, their topological surface states on the top and bottom surfaces exhibit p-type and n-type carriers, respectively. Thus, these materials may serve as an ideal platform for the realization of topological magneto-electric effects as polar topological insulators. Moreover, these topological surface states exhibit the right-hand spin-texture in the upper Dirac cone, which distinguish them from currently known topological insulator materials. Their topological nontrivial character remains robust against in-plane strains, which makes them suitable for epitaxial growth of films.3

Machine learning (ML) methods were applied to predict the capacitance of carbon-based supercapacitors.

With the coming of the "energy internet," the pursuit of ultralong-life electrode materials has triggered the unprecedented scientific research toward novel energy storage systems, instead of the conventional lithium-ion batteries (LIBs). Owing to the limited Li resources and unsatisfactory poor cycling performance, [1][2][3][4] the development of high-capacity electrode materials with ultrastable cycling performance is the key for the next generation of energy storage battery. To this end, sodium-ion batteries (SIBs) and lithium-sulfur (Li-S) batteries are emerging as competitive alternatives because of the abundant resources of Na and S. [5][6][7][8] Great effort have been devoted to exploring new electrode materials in SIBs. [9] Among them, titanium dioxide (TiO 2 ) has been intensively studied as anode material for SIBs, due to its relatively little volume expansion. [10][11][12] Nevertheless, its slow sodium diffusion and relatively low intrinsic electronic conductivity hinder its implementation in SIBs,The development of electrode materials with superior cycling stability is currently receiving intensive research for next-generation portable electronic equipment. Herein, a novel 3D hierarchical architecture composed of TiO 2 /epitaxially aligned MoS 2 -carbon coupled interface nanosheets is reported for boosting sodium-ion storage and lithium-sulfur batteries, in which the MoS 2 nanosheets are epitaxially aligned grown on the surface of carbon nanosheets through a simple calculation conversion process. The resulting hybrid demonstrates ultralong-life performance for sodium-ion storage and lithium-sulfur batteries, owing to synergistic effects among the stable TiO 2 nanowires, the high-conductivity carbon nanosheets, and the vertical MoS 2 nanostructure. Even at a high current density of 8 A g −1 , the capacity can be maintained at 169 mA h g −1 after 15 000 cycles, one of the highest values for TiO 2 -based electrodes. Moreover, such peculiar sheet-onsheet structure also brings benefits for lithium-sulfur batteries, providing an effective physical shield against polysulfide shuttling and chemical adsorption of polysulfides, with a low fading rate (0.039% per cycle over 1500 cycles). The present work highlights that this rationally designed hybrid nanoarchitecture is an effective strategy to boost the stability of electrochemical energy storage.

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