Charge Carrier Transfer in Ta3N5 Photoanodes Prepared by Different Methods for Solar Water Splitting

The preparation method of a photoanode can affect its water splitting property. Here, as examples, we prepared Ta3N5 photoanodes by an electrophoresis deposition (EPD) method and an oxidation and nitridation of Ta foil (ONTF) method. The light harvest, interfacial charge transfer, and charge separation of the two Ta3N5 photoanodes were analysed to gain insight into the role of the preparation method on the water splitting property. The results suggested that the ONTF-prepared Ta3N5 showed a higher solar energy conversion efficiency, arising from its better interfacial charge transfer efficiency and higher charge separation efficiency. The higher charge separation efficiency was mainly attributed to good electron transfer, and the inter-particle connectivity was key for the electron transfer in the photoanodes. Especially, the dense, small particle structure of ONTF-prepared Ta3N5 was beneficial for increasing the connectivity between inter-particles. This comparison of preparation methods can be used as a reference for future photoanode preparation to improve the water splitting property of photoelectrochemical cells.

The social acceptance of artificial photosynthesis: towards a conceptual framework

Advancements in artificial photosynthesis have the potential to radically transform how societies convert and use energy. Their successful development, however, hinges not only on technical breakthroughs, but also acceptance and adoption by energy users. This article introduces a conceptual framework enabling analysts, planners and even investors to determine environments where artificial photosynthesis may thrive, and those where it may struggle. Drawn from work looking at the barriers and acceptance of solar photovoltaic and wind energy systems, the article proposes that social acceptance has multiple dimensions-socio-political, community and market-that must be met holistically in order for investors and users to embrace new technologies. The article argues that any future market acceptance for artificial photosynthesis will depend upon the prevalence of nine factors, which create conducive environments; the lack of the conditions engenders environments where they will likely be rejected. The conditions are (i) strong institutional capacity; (ii) political commitment; (iii) favourable legal and regulatory frameworks; (iv) competitive installation and/or production costs; (v) mechanisms for information and feedback; (vi) access to financing; (vii) prolific community and/or individual ownership and use; (viii) participatory project siting; and (ix) recognition of externalities or positive public image.