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Photoinduced syntheses offer significant advantages over conventional thermal strategies, including improved control over reaction kinetics and low synthesis temperatures, affording nanoparticles with nontrivial and thermodynamically unstable structures. However, the photoinduced syntheses of non-metallic nanocrystalline products (such as metal sulfides) have not yet been reported. Herein, we demonstrate the first photoinduced synthesis of ultrafine (sub-2 nm) Ag 2 S quantum dots (QDs) from Ag nanoparticles at 10 °C. By thorough investigation of the mechanism for the transformation, a fundamental link was established between the intrinsic structures of the molecular intermediates and the final Ag 2 S products. Our results confirm the viability of low-temperature photochemical approaches in metal sulfide synthesis, and demonstrate a new rule which could be followed in it., (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Efficient capture of solar energy will be critical to meeting the energy needs of the future. Semiconductor photocatalysis is expected to make an important contribution in this regard, delivering both energy carriers (especially H 2 ) and valuable chemical feedstocks under direct sunlight. Over the past few years, carbon dots (CDs) have emerged as a promising new class of metal-free photocatalyst, displaying semiconductor-like photoelectric properties and showing excellent performance in a wide variety of photoelectrochemical and photocatalytic applications owing to their ease of synthesis, unique structure, adjustable composition, ease of surface functionalization, outstanding electron-transfer efficiency and tunable light-harvesting range (from deep UV to the near-infrared). Here, recent advances in the rational design of CDs-based photocatalysts are highlighted and their applications in photocatalytic environmental remediation, water splitting into hydrogen, CO 2 reduction, and organic synthesis are discussed., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Mesoporous carbon nanospheres containing porphyrin-like metal centers (denoted as "PMCS") are successfully synthesized by the pyrolysis of an imidazolate framework using a mesoporous-silica protection strategy. The PMCS allow infrared and photoacoustic imaging and synergetic photothermal therapy/photodynamic therapy derived from the porphyrin-like moieties, offering the possibility of real-time monitoring of therapeutic processes and image-guided precise conformal phototherapy. PMCS thus represent a novel multifunctional theranostic platform for improved treatment efficiencies., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A simple seaweed biomass conversion strategy is proposed to synthesize highly porous multishelled Ni-rich Li(Ni x Co y Mn z )O 2 hollow fibers with very low cation mixing. The low cation mixing results from the cation confinement by the novel "egg-box" structure in the alginate template. These hollow fibers exhibit remarkable energy density, high-rate capacity, and long-term cycling stability when used as cathode material for Li-ion batteries.

T. Zhang and co-workers report the synthesis of nitrogen-doped porous carbon nanosheets with extremely high nitrogen content and high surface areas using graphitic carbon nitride (g-C3 N4 ) as template, nitrogen source, and porogen. As described on page 5080, the nanosheets exhibit outstanding oxygen reduction catalytic activities which are comparable to commercial Pt/C catalysts in alkaline media., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Nitrogen-doped porous carbon nanosheets (N-CNS) are synthesized by hydrothermal carbon coating of g-C3 N4 nanosheets followed by high-temperature treatment in N2 . g-C3 N4 serves as a template, nitrogen source, and porogen in the synthesis. This approach yields N-CNS with a high nitrogen content and comparable oxygen reduction reaction catalytic activities to commercial Pt/C catalysts in alkaline media., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A well-dispersed Co,N co-doped carbon nanoframework (Co,N-CNF) with hierarchically porous structure is successfully synthesized from zeolitic imidazolate framework (ZIF) precursors via a mesoporous-silica-protected calcination strategy. By preventing the irreversible fusion and aggregation during the high-temperature pyrolysis step with this protection strategy, the Co,N-CNF exhibits comparable oxygen reduction reaction (ORR) catalytic activity to that of commercial Pt catalysts with the same loading., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Monovalent Zn + (3d 10 4s 1 ) systems possess a special electronic structure that can be exploited in heterogeneous catalysis and photocatalysis, though it remains challenge to synthesize Zn + -containing materials. By careful design, Zn + -related species can be synthesized in zeolite and layered double hydroxide systems, which in turn exhibit excellent catalytic potential in methane, CO and CO 2 activation. Furthermore, by utilizing advanced characterization tools, including electron spin resonance, X-ray absorption fine structure and density functional theory calculations, the formation mechanism of the Zn + species and their structure-performance relationships can be understood. Such advanced characterization tools guide the rational design of high-performance Zn + -containing catalysts for efficient energy conversion.

Defect-rich ultrathin ZnAl-layered double hydroxide nanosheets are successfully prepared. Under UV-vis irradiation, these nanosheets are superior efficient catalysts for the photoreduction of CO2 to CO with water. The formed oxygen vacancies lead to the formation of coordinatively unsaturated Zn(+) centers within the nanosheets, responsible for the very high photocatalytic activities., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The mixed-phase nature of P25 TiO2 (85 % anatase/15 % rutile) plays a key role in the high H2 production rates shown by Au/P25 TiO2 photocatalysts in alcohol/water systems. However, a full understanding of the synergistic charge transfer mechanisms between the TiO2 polymorphs that drive the high rates is yet to be realised. Here, we deconstruct P25 TiO2 into its component phases, functionalise the phases with Au nanoparticles and explore charge transfer in Au/TiO2 systems using EPR spectroscopy. EPR spectroscopy and photocatalytic data provide direct evidence that electrons excited across the rutile band gap move to anatase lattice traps through interfacial surface sites, which decreases electron-hole pair recombination and increases charge carrier availability for photoreactions. In particular, three-phase interfacial sites between Au, anatase and rutile appear to be H2 evolution "hot spots". The results isolate the origin of high photocatalytic H2 production rates seen in Au/P25 TiO2 systems., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)