Rechargeable zinc–air batteries show great potential in applications such as electric vehicles and wearable devices, especially for the flexible design. And the challenges and functional materials for each component are provided and discussed from air electrode, solid-state electrolyte to zinc anode, with perspectives of research directions.

2D materials are ideal for constructing flexible electrochemical energy storage devices due to their great advantages of flexibility, thinness, and transparency. Here, a simple one‐step hydrothermal process is proposed for the synthesis of nickel–cobalt phosphate 2D nanosheets, and the structural influence on the pseudocapacitive performance of the obtained nickel–cobalt phosphate is investigated via electrochemical measurement. It is found that the ultrathin nickel–cobalt phosphate 2D nanosheets with an Ni/Co ratio of 4:5 show the best electrochemical performance for energy storage, and the maximum specific capacitance up to 1132.5 F g−1. More importantly, an aqueous and solid‐state flexible electrochemical energy storage device has been assembled. The aqueous device shows a high energy density of 32.5 Wh kg−1 at a power density of 0.6 kW kg−1, and the solid‐state device shows a high energy density of 35.8 Wh kg−1 at a power density of 0.7 kW kg−1. These excellent performances confirm that the nickel–cobalt phosphate 2D nanosheets are promising materials for applications in electrochemical energy storage devices.

Light flux from LED must be redistributed to meet the needs of lighting in most cases, a new method is proposed for its secondary optic design. Based on refractive equation and energy conservation, a set of first-order partial differential equations which represent the characters of LED source and desired illumination were presented. The freeform lens was constructed by solving these equations numerically. The numerical results showed that we can get a freeform lens for the illumination of uniformity near to 90%, with considerable high computation speed. This method can shorten the designing time of the freeform lens with high accepted tolerance.

We have successfully synthesized an accordion-like Ni-MOF superstructure for high-performance flexible supercapacitors.

Controlled synthesis for electrode materials and excellent electrochemical performances were introduced for advanced supercapacitors.

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We extend the visible content of the standard model (SM) with a hidden sector composed of three right-handed singlet neutrinos and one singlet Higgs. These extra singlets are charged under a new U (1) X gauge symmetry while the SM particles are not. Two heavy scalar doublets are introduced to play the role of the messengers between the visible and hidden sectors. The neutrinos naturally acquire tiny Dirac masses because the ratio of weak scale over the heavy messenger masses is highly suppressed. Furthermore, the heavy messengers simultaneously generate baryon asymmetry of the universe through their out-of-equilibrium CP-violating decays. PACS: 98.80.-k; 11.30.Er, 14.60.Pq [ hep-ph/0610275 ] The tiny neutrino masses and the matter-antimatter asymmetry in the universe pose two major challenges to particle physics and cosmology. This indicates the necessity of supplementing to the existing theory certain new ingredients, which have been hidden from the direct experimental observations so far [1].In this paper, we propose a novel Dirac Seesaw model to obtain the tiny neutrino masses and generate the observed baryon asymmetry by extending the visible content of the standard model (SM) with a hidden sector which is prescribed by a U (1) X gauge symmetry and composed of three right-handed singlet neutrinos plus one singlet Higgs. Two heavy scalar doublets are introduced to play the role of messengers between the visible and hidden sectors.The field content of the proposed SU (2) L ⊗ U (1) Y ⊗ U (1) X model is defined in Table I, where ψ L , φ, ν R , χ, η are the left-handed lepton doublets, the Higgs doublet, the right-handed singlet neutrinos, the singlet Higgs and the heavy scalar doublets, respectively. All other unlisted SM fields are U (1) X singlets. In this Table we have also suppressed the generation indices for simplicity. It is clear that the conventional Yukawa couplings of the left-handed lepton doublets and the right-handed singlet neutrinos with the light Higgs doublet φ are forbidden because the right-handed neutrinos have U (1) X charge while all the SM particles do not. Namely, the sector composed of the right-handed neutrinos and the Higgs singlet is hidden from the visible SM sector. However, the heavy scalar doublets η, which join not only the SM gauge group SU (2) L ⊗ U (1) Y but also the new U (1) X , can bridge the two sectors. In this sense, we may regard the heavy scalar doublets as "messengers".We can thus write down the relevant interaction Lagrangian for generating the Dirac neutrino masses. It involves the messenger scalars η, the SM-like doublet φ and the singlet scalar χ , L ⊃ −y ψ L ην R + ρχη † φ + h.c. ,(1) *