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The notorious polysulfide shuttle effect is a crucial factor responsible for the degradation of Li-S batteries. A good way to suppress the shuttle effect is to effectively anchor dissoluble lithium polysulfides (LPSs, Li 2 S n ) on appropriate substrates. Previous studies have revealed that Li of Li 2 S n is prone to interact with the N of N-containing materials to form Li–N bonds. In this work, by means of density functional theory (DFT) computations, we explored the possibility to form Li bonds on ten different N-containing monolayers, including BN, C 2 N, C 2 N 6 S 3 , C 9 N 4 , a covalent triazine framework (CTF), g -C 3 N 4 , p -C 3 N 4 , C 3 N 5 , S -N 2 S, and T -N 2 S, by examining the adsorption behavior of Li 2 S n ( n = 1, 2, 3, 4, 6, 8) on these two-dimensional (2D) anchoring materials (AMs), and investigated the performance of the formed Li bonds (if any) in inhibiting the shuttle effect. By comparing and analyzing the nitrogen content, the N-containing pore size, charge transfer, and Li bonds, we found that the N content and N-containing pore size correlate with the number of Li bonds, and the formed Li–N bonds between LPSs and AMs correspond well with the adsorption energies of the LPSs. The C 9 N 4 and C 2 N 6 S 3 monolayers were identified as promising AMs in Li-S batteries. From the view of Li bonds, this work provides guidelines for designing 2D N-containing materials as anchoring materials to reduce the shuttle effect in Li-S batteries, and thus improving the performance of Li-S batteries. 

Efficient control of photons is enabled by hybridizing light with matter. The resulting light-matter quasi-particles can be readily programmed by manipulating either their photonic or matter constituents. Here, we hybridized infrared photons with graphene Dirac electrons to form surface plasmon polaritons (SPPs) and uncovered a previously unexplored means to control SPPs in structures with periodically modulated carrier density. In these periodic structures, common SPPs with continuous dispersion are transformed into Bloch polaritons with attendant discrete bands separated by bandgaps. We explored directional Bloch polaritons and steered their propagation by dialing the proper gate voltage. Fourier analysis of the near-field images corroborates that this on-demand nano-optics functionality is rooted in the polaritonic band structure. Our programmable polaritonic platform paves the way for the much-sought benefits of on-the-chip photonic circuits.