Artificial Leaf for Water Splitting Based on a Triple‐Junction Thin‐Film Silicon Solar Cell and a PEDOT:PSS/Catalyst Blend

Abstract

An integrated water‐splitting device based on a triple‐junction silicon‐based solar cell (a‐Si:H/a‐Si:H/μc‐Si:H; a‐Si=amorphous silicon, μc‐Si=microcrystalline) in superstrate configuration modified with catalysts at the back and front contacts is described. In this configuration, the solar cell is illuminated by the glass substrate, while the back and front contacts are arrayed laterally at the opposite side of the cell. Therefore, neither shadowing nor light scattering by evolved gas bubbles can detrimentally affect the solar‐to‐hydrogen efficiency of this artificial leaf. By modifying the contact layers of the cell, its chemical stability in acid electrolyte is significantly improved. To test the system, RuO2 and Pt black catalysts are fixed on the contacts as a blend by using a conductive polymer [poly(3,4‐ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS)]. A solar‐to‐hydrogen efficiency of 3.4 % is obtained under AM1.5G illumination and 1000 W m−2 in 0.5 M H2SO4 without applying any external bias. The device shows only 6 % loss of efficiency within 17 h of operation.

Evaluation of electrodeposited α-Mn 2 O 3 as a catalyst for the oxygen evolution reaction

“…This is clearly a non-tolerable loss of efficiency. However, for application as a catalyst on the backcontact of a photoelectrode in superstrate geometry [31], highly porous α-Mn 2 O 3 electrodes could be a promising and cheap alternative to noble metal-and even nickelbased catalysts.…”

Toward a Low‐Cost Artificial Leaf: Driving Carbon‐Based and Bifunctional Catalyst Electrodes with Solution‐Processed Perovskite Photovoltaics

“…In this challenging context, researchers have found inspiration in the process of natural photosynthesis when they attempt to convert the plentiful, but intermittent, solar irradiation incident on the Earth's surface into a storable fuel, using a range of methods commonly coined as artifi cial photosynthesis. [1][2][3][4][5][6][7][8][9] One emerging technology to achieve such solar-to-fuel conversion is the "artifi cial-leaf device", which essentially comprises an assembly of photovoltaics (PVs) that drives two electrocatalyst electrodes immersed in water. [10][11][12] This device produces molecular hydrogen and oxygen using only sunlight and water as the input, and during the past few years its performance has improved drastically, with the current record for the solar-to-hydrogen (STH) conversion efficiency being above 10%.…”

Architectures for scalable integrated photo driven catalytic devices-A concept study

“…catalysts [28]. Stellmach et al have reached 2.5% with the noble metal free HER catalyst MoS 2 catalyst in a complete wireless 'artificial leaf' configuration [29]. According to the classification of Modestino and Haussener, such a device would be labeled a PV/electrolysis device [12], although it could be in principle fabricated entirely monolithic.…”