Volume 1 Issue 8 August 2016

Volume 1 Issue 8

The many facets of efficiency

The local structural properties of organic–inorganic perovskites affect their photovoltaic response, but it is challenging to quantify such effects at the scale of single grains. Leblebici et al. show that such properties are heterogeneous within individual grains due to a facet-dependent density of trap states.

See Leblebici et al. 1, 16093 (2016).

Image: Sibel Leblebici. Cover design: Karen Moore.

Editorial

  • Editorial |

    Using hydrogen as an energy carrier has long been discussed as a route to a greener future, and although headway has been less significant than many hoped, recent developments point to tangible progress.

Feature

Research Highlights

News & Views

  • News and Views |

    Energy-saving programmes are increasingly targeted at children to encourage household energy conservation. A study involving the assignment of energy-saving interventions to Girl Scouts shows that a child-focused intervention can improve energy-saving behaviours among children and their parents.

    • Alice Grønhøj
  • News and Views |

    The electronic properties of halide perovskites vary significantly between crystalline grains, but the impact of this heterogeneity on solar cell performance is unclear. Now, this variability is shown to limit the photovoltaic properties of solar cells, and its origins are linked to differing properties between crystal facets.

    • Giles E. Eperon
    •  & David S. Ginger
  • News and Views |

    In the development of lithium–air batteries, managing the phase change between gaseous oxygen and crystalline lithium peroxide is a key challenge. Now, a high-performing sealed battery with an oxygen anion-redox electrode is presented that does not involve any gas evolution.

    • Laurence J. Hardwick
  • News and Views |

    Electricity distribution system planners rely on estimations of future energy demand to build adequate supply, but these are complicated to achieve. An approach that combines spatially resolved projections of population movement and climate change offers a method for building better demand maps to mid-century.

    • Anthony C. Janetos

Perspective

  • Perspective |

    Cheap energy can encourage economic growth but it can also force economies into specific energy-intensive futures. Roger Fouquet argues that path dependence in energy systems has profound implications for an economy and should be considered carefully before governments make choices about energy provision.

    • Roger Fouquet

Research

  • Article |

    Behavioural interventions targeting children can influence the whole family, making them attractive for energy-saving schemes. Boudet et al. use 30 Girl Scout groups to test interventions on residential and food and transport energy behaviours and find they have potential for increasing energy saving.

    • Hilary Boudet
    • , Nicole M. Ardoin
    • , June Flora
    • , K. Carrie Armel
    • , Manisha Desai
    •  & Thomas N. Robinson
  • Article |

    The photovoltaic properties of hybrid organic–inorganic perovskites are sensitive to the local microstructure, but difficult to quantify at the nanoscale. Leblebici et al. use conductive atomic force microscopy to map the local short-circuit current and open-circuit voltage, finding heterogeneity within individual grains.

    • Sibel Y. Leblebici
    • , Linn Leppert
    • , Yanbo Li
    • , Sebastian E. Reyes-Lillo
    • , Sebastian Wickenburg
    • , Ed Wong
    • , Jiye Lee
    • , Mauro Melli
    • , Dominik Ziegler
    • , Daniel K. Angell
    • , D. Frank Ogletree
    • , Paul D. Ashby
    • , Francesca M. Toma
    • , Jeffrey B. Neaton
    • , Ian D. Sharp
    •  & Alexander Weber-Bargioni
  • Article |

    A common problem for thick electrodes in lithium-ion batteries is slow ionic transport. Here, the authors present a particle-alignment method that uses a low magnetic field and show that the lithium diffusion path is improved for an aligned thick graphite electrode, leading to a better rate capability.

    • Juliette Billaud
    • , Florian Bouville
    • , Tommaso Magrini
    • , Claire Villevieille
    •  & André R. Studart
  • Article |

    Electrode materials with pores generally have high tortuosity, which is detrimental to battery performance. Here the authors develop a magnetic alignment approach that produces battery electrodes with low-tortuosity porosity and high capacity.

    • J. S. Sander
    • , R. M. Erb
    • , L. Li
    • , A. Gurijala
    •  & Y.-M. Chiang
  • Article |

    Future regional electricity demand will be affected by climate change and population migration. Allen et al. combine predictions of temperature rise and population shift, including in response to extreme weather, to map electricity demand and substation capability in the southern US to 2050.

    • Melissa R. Allen
    • , Steven J. Fernandez
    • , Joshua S. Fu
    •  & Mohammed M. Olama
  • Article |

    The significant phase change between gaseous and crystalline oxygen deteriorates the performance of lithium–air batteries. Here the authors report a battery with a cathode consisting of Li2O and Co3O4 nanocomposites, which displays stable cyclability and high energy density, without involving any gas evolution.

    • Zhi Zhu
    • , Akihiro Kushima
    • , Zongyou Yin
    • , Lu Qi
    • , Khalil Amine
    • , Jun Lu
    •  & Ju Li