From leaf to tree: upscaling of artificial photosynthesis

TL;DR

This paper presents a scalable, integrated artificial photosynthesis device compatible with thin-film photovoltaics, demonstrating stable operation and a 3.9% solar-to-hydrogen efficiency, advancing large-scale renewable energy storage.

Contribution

Introduces a novel scalable design for artificial photosynthesis devices that can be independently optimized and easily expanded for large-area applications.

Findings

Achieved a 3.9% solar-to-hydrogen efficiency.

Demonstrated stable, bias-free operation for 40 hours.

Scalable design with 13 base units over 64 cm² area.

Abstract

Energy storage becomes crucial for energy systems with an increasing share of renewable energy sources. Artificial photosynthesis, in particular photovoltaic water splitting, provides both sustainable energy generation and energy storage in the form of hydrogen. However, only a few concepts for scalable devices were reported in the literature. Here, we introduce a new concept which, by design, is scalable and compatible with every thin-film photovoltaic technology. The concept allows for independent geometrical optimization of the photovoltaic and the electrochemical part. The scalability is achieved by continuous mirroring of a base unit. We demonstrate a fully integrated, wireless device with a stable and bias-free operation for 40 hours. The concept was scaled to an area of 64 cm2 comprising 13 base units and exhibited a solar-to-hydrogen efficiency of 3.9%. The concept and its successful realization is an important contribution towards the large scale application of artificial photosynthesis.