Volume 5 Issue 6, June 2020

Li₄Ti₅O₁₂ is a commonly used negative electrode material, but the origin of its fast rate capability has puzzled scientists for decades. Now, a facile Li-ion transport route featuring metastable intermediates is revealed to rationalize the fast-charging kinetics.

Light-driven production of hydrogen by coupling natural photosystems or photosensitizers with hydrogen-producing catalysts has been achieved in numerous in vitro systems. Now, a recombinant in vivo system is described that generates hydrogen using a hydrogenase enzyme directly coupled to a cyanobacterial photosystem.

Dye-sensitized solar cells are promising as power-generating solar windows yet their fixed transparency prevents control of indoor lighting and temperature. Researchers now present a device that dynamically self-adjusts its optical transmittance with sunlight intensity, opening up a way to energy-efficient self-powered building façades.

While the Pradhan Mantri Ujjwala Yojana has been instrumental in increasing India’s liquefied petroleum gas adoption, sustained use depends on factors such as regularity of income and ease of access to free-of-cost biomass. To ensure sustained use after adoption, interventions in clean cooking energy must tie in with broader rural development.

Despite its prevalence, energy poverty is not formally recognized in the US as a problem distinct from general poverty. This Review of two federally-funded programs focused on reducing high energy bills highlights the limitations of this approach for effectively responding to energy poverty.

Low energy density and limited cyclability are preventing the commercialization of aqueous Zn–MnO₂ batteries. Here, the authors combine the merits of operating Zn anodes in alkaline conditions and MnO₂ cathodes in acidic conditions, via an electrolyte-decoupling strategy, to realize high-performance batteries.

It is not clear what factors drive sustained use of clean cooking fuels after adoption in places such as India and China. With India achieving a liquified petroleum gas penetration of 95%, Mani et al. use longitudinal data from a survey of more than 8,000 rural households to identify the reasons for the uptake and sustained use of the clean fuel.

Using photosynthetic microorganisms may be a route to sustainable hydrogen production from solar energy, but hydrogen generation is typically short lived. Here the authors address this challenge by engineering cyanobacteria to construct photosystem I–hydrogenase fusions that produce hydrogen in vivo.

Building-integrated installation of semi-transparent solar cells is limited by a trade-off between transparency and efficiency. Now, Huaulmé et al. demonstrate dye-sensitized solar cells with photochromic sensitizers that adjust their light transmission and power conversion efficiency with light exposure.

The electroreduction of CO₂ to ethanol could enable the clean production of fuels using renewable power. This study shows how confinement effects from nitrogen-doped carbon layers on copper catalysts enable selective ethanol production from CO₂ with a Faradaic efficiency of up to 52%.