The design of an environmentally benign cost-effective adsorbent for superfast removal of phosphate from wastewater is vital but remains a huge challenge.

No abstract

Solid electrolytes have attracted much attention due to their great prospects in a number of energy- and environment-related applications including fuel cells. Fast ion transport and superior mechanical properties of solid electrolytes are both of critical significance for these devices to operate with high efficiency and long-term stability. To address a common tradeoff relationship between ionic conductivity and mechanical properties, electrolyte membranes with proton-conducting 2D channels and nacre-inspired architecture are reported. An unprecedented combination of high proton conductivity (326 mS cm at 80 °C) and superior mechanical properties (tensile strength of 250 MPa) are achieved due to the integration of exceptionally continuous 2D channels and nacre-inspired brick-and-mortar architecture into one materials system. Moreover, the membrane exhibits higher power density than Nafion 212 membrane, but with a comparative weight of only ≈0.1, indicating potential savings in system weight and cost. Considering the extraordinary properties and independent tunability of ion conduction and mechanical properties, this bioinspired approach may pave the way for the design of next-generation high-performance solid electrolytes with nacre-like architecture.

No abstract

We report results of large-scale ground-state density matrix renormalization group (DMRG) calculations on t-t′-J cylinders with circumferences 6 and 8. We determine a rough phase diagram that appears to approximate the two-dimensional (2D) system. While for many properties, positive and negative t′ values (t′/t=±0.2) appear to correspond to electron- and hole-doped cuprate systems, respectively, the behavior of superconductivity itself shows an inconsistency between the model and the materials. The t′<0 (hole-doped) region shows antiferromagnetism limited to very low doping, stripes more generally, and the familiar Fermi surface of the hole-doped cuprates. However, we find t′<0 strongly suppresses superconductivity. The t′>0 (electron-doped) region shows the expected circular Fermi pocket of holes around the (π,π) point and a broad low-doped region of coexisting antiferromagnetism and d-wave pairing with a triplet p component at wavevector (π,π) induced by the antiferromagnetism and d-wave pairing. The pairing for the electron low-doped system with t′>0 is strong and unambiguous in the DMRG simulations. At larger doping another broad region with stripes in addition to weaker d-wave pairing and striped p-wave pairing appears. In a small doping region near x=0.08 for t′∼−0.2, we find an unconventional type of stripe involving unpaired holes located predominantly on chains spaced three lattice spacings apart. The undoped two-leg ladder regions in between mimic the short-ranged spin correlations seen in two-leg Heisenberg ladders.

No abstract

The normal state of cuprate superconductors exhibits many exotic behaviors qualitatively different from the Fermi liquid, the foundation of condensed matter physics. Here we demonstrate that non-Fermi liquid behaviors emerge naturally from scattering against an emergent Bose liquid. Particularly, we find a finite zero-energy scattering rate at the low-temperature limit that grows linearly with respect to temperature, against clean fermions' generic nondissipative characteristics. Surprisingly, three other seemingly unrelated experimental observations are also produced, including the well-studied "kink" in the quasiparticle dispersion, as well as the puzzling correspondences between the normal and superconducting state. Our findings provide a general route for fermionic systems to generate non-Fermi liquid behavior and suggest that by room temperature large number of the doped holes in the cuprates have already formed an emergent Bose liquid of tightly bound pairs, whose low-temperature condensation gives unconventional superconductivity.

No abstract