Solid polymer electrolytes (SPEs) are desirable in lithium metal batteries (LMBs) since they are nonflammable and show excellent lithium dendrite growth resistance. However, fabricating high performance polymer LMBs is still a grand challenge because of the complex battery system. In this work, a series of tailor-designed hybrid SPEs were used to prepare LMBs with a LiFePO 4 -based cathode. High performance LMBs with both excellent rate capability and long cycle life were obtained at 60 and 90 C. The well-controlled network structure in this series of hybrid SPEs offers a model system to study the relationship between the SPE properties and the LMB performance. We show that the cycle life of the polymer LMBs is closely correlated with the SPE|Li interface ionic conductivity, underscoring the importance of the solid electrolyte interface in LMB operation. LMB performance was further correlated with the molecular network structure.We anticipate that results from this study will shed light on designing SPEs for high performance LMB applications.

Precise synthesis of polymer brushes to modify the surface of nanoparticles and nanodevices for targeted applications has been one of the major focuses in the community for decades. Here we report a self-assembly-assisted-grafting-to approach to synthesize polymer brushes on flat substrates. In this method, polymers are pre-assembled into two-dimensional polymer single crystals (PSCs) with functional groups on the surface. Chemically coupling the PSCs onto solid substrates leads to the formation of polymer brushes. Exquisite control of the chain folding in PSCs allows us to obtain polymer brushes with well-defined grafting density, tethering points and brush conformation. Extremely high grafting density (2.12 chains per nm2) has been achieved in the synthesized single-tethered polymer brushes. Moreover, polymer loop brushes have been successfully obtained using oddly folded PSCs from telechelic chains. Our approach combines some of the important advantages of conventional ‘grafting-to' and ‘grafting-from' methods, and is promising for tailored synthesis of polymer brushes.

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We describe a previously not reported “one-pot” synthesis of nanocrystalline Ag(0)/CaTiO3 in aqueous suspension and the following in situ photocatalytic testing in the same suspension to generate hydrogen. The Ag(0)/CaTiO3 showed an enhancement of photocatalytic hydrogen generation rate vs CaTiO3 precursor. The obtained Ag(0)/CaTiO3 photocatalyst was ex situ characterized by XPS, XRD, UV–vis diffuse reflectance spectroscopy (DRS), and photoluminescence (PL) spectroscopy, and concluded to have metallic silver nanoparticles on the surface of calcium titanate nanocrystals. The three photocatalytic mechanisms in Ag(0)/CaTiO3 were considered: (a) bandgap narrowing in CaTiO3, (b) enhanced electron–hole separation in CaTiO3, and (c) excitation of surface plasmon resonance (SPR) in metallic Ag nanoparticles. In mechanistic studies, photocatalytic suspensions with CaTiO3 precursor, with silver precursor, and with both CaTiO3 and Ag precursors to form Ag(0)/CaTiO3 were illuminated, flash-frozen to 77 K, and characterized by in situ “conventional” PL spectroscopy and in situ synchronous luminescence spectroscopy. On the basis of the complementary ex situ and in situ studies, an enhanced electron–hole separation in Ag(0)/CaTiO3 is suggested.

For the sustainable production of hydrogen by photocatalysis, the use of renewable resources such as water, organic compounds from plant biomass and earth abundant metal promoters is desired. We herein describe the previously not reported "one-pot" photoassisted synthesis of a binary metal-nitrogen promoted Cu(0)-N-TiO photocatalyst from a N-TiO precursor by photodeposition of copper directly in the photocatalytic suspension. The N-TiO contains nanocrystalline anatase as found by XRD and Raman spectroscopy. X-ray Photoelectron Spectroscopy (XPS) and Electron Spin Resonance (ESR) spectroscopy indicate that a nitrogen promoter is present as a substitutional site. The scheme of relaxation of a photoexcited charge through a substitutional nitrogen induced midgap states in N-TiO is proposed. The binary promoted Cu(0)-N-TiO photocatalyst prepared from N-TiO by "one-pot" photodeposition of copper in the suspension showed a high activity in the in situ hydrogen generation under near-UV/visible light with glycerol in water, up to 675 μmol g h. The "one-pot" photoassisted synthesis and mechanism of operation of the Cu(0)-N-TiO photocatalyst are studied by the complementary in situ spectroscopic methods.