  Although photoelectrochemical water splitting is likely to be an important
and powerful tool to provide environmentally friendly hydrogen, most
developments in this field have been conducted on a laboratory scale so far. In
order for the technology to make a sizeable impact on the energy transition,
scaled up devices made of inexpensive and earth abundant materials must be
developed. In this work, we demonstrate a scalable (64 cm2 aperture area)
artificial photoelectrochemical device composed of triple-junction thin-film
silicon solar cells in conjunction with an electrodeposited bifunctional nickel
iron molybdenum water splitting catalyst. Our device shows a solar to hydrogen
efficiency of up to 4.67% (5.33% active area) without bias assistance and wire
connection. Furthermore, gas separation was enabled by incorporating a membrane
in a 3D printed device frame.
