William B. Ingler

A Self-Driven p ∕ n‐Fe2O3 Tandem Photoelectrochemical Cell for Water Splitting

It is desirable to fabricate self-driven photoelectrochemical cells (PECs) utilizing low cost, low bandgap, and stable materials for efficient splitting of water into hydrogen. We report here the spray pyrolytically fabricated self-driven tandem p/n-Fe 2 O 3 PECs for photoelectrochemical water splitting. The combination of p-Fe 2 O 3 synthesized by zinc doping using ethanol as the spray solvent and the undoped n-Fe 2 O 3 synthesized using 1-pentanol as the spray solvent generated the self-driven photoelectrochemical cell for water splitting.

A Single Chip Standalone Water Splitting Photoelectrochemical Cell

Water splitting photoelectrochemical cell (PEC) was fabricated in which the electrolyzer parts were made on a single chip. This was achieved by depositing an optically transparent Mn-oxide-TiO 2 thin layer on the front of a triple junction amorphous Si photovoltaic cell which acted as the anode and the back stainless steel layer acted as the cathode under illumination of light. This single chip water electrolysis cell operates like an artificial leaf. Water splitting was observed by simply submersing the device in a basic electrolyte solution under solar simulated light of 1 sun (0.1 W cm -2 ). This self-driven PEC was found to produce hydrogen gas at the rate of 12.42 L m -2 h -1 and a solar to hydrogen efficiency (STHE) of 3.25 % from the collected H 2 gas in 2.5 M KOH solution. No signs of degradation of this single chip PEC were observed during water splitting when the device was run continuously for 6 hours.

Efficient Anode and Cathode Materials for Amorphous Silicon Solar Cell Driven all Solar Electrolysis of Water

Abstract Few non-noble metal based anode and cathode materials were investigated for all solar electrolysis of water to hydrogen and oxygen gases powered by double junction amorphous silicon (Dj-a-Si) solar cell under solar simulated light of 1 sun. The highest hydrogen generation current efficiency of 58.68% was obtained when Pt wire was used as a cathode with the non-noble metal based Ni-Co3 O4 as an anode in the electrochemical cell. However, when Pt metal was replaced by a non-noble metal Ni as cathode, the maximum hydrogen generation current efficiency of 51.28% was observed. This corresponds to a 7.4% loss in current efficiency when Pt cathode was replaced by Ni. The percent solar to hydrogen conversion efficiencies (% STH) were found to be 8.66% and 7.57% for the Dj-a-Si solar cell driven electrolysis of water in the Ni-Co3O4‖Pt and non-noble metal based Ni-Co3O4‖Ni electrochemical cells respectively. Notably, the lowest hydrogen generation current efficiency of 36.33% and % STH efficiency of 5.36% were obtained when Pt metal was used as both anode and cathode in Pt‖Pt electrochemical cell.

In Search of Efficient Anode and Cathode Materials for Double Junction Amorphous Silicon Solar Cell Driven all Solar Electrolysis of Water to Hydrogen and Oxygen Gases

INTRODUCTION The best way to produce pure hydrogen is by electrolysis and photoelectrolysis of water. Much research activities are in progress for direct photoelectrolysis of water . For the solar cell driven electrolysis of water to be cost effective the solar cells must be efficient, low cost and most importantly the anode and cathode materials should be also cost effective and non-noble metal based. In this work we report the hydrogen generation current, hydrogen current efficiency and the photoconversion efficiency of combination of few anode and cathode materials for water electrolysis driven by double junction amorphous silicon solar cells (DJ-a-Si). Amorphous Si solar cells are more cost effective compared to single crystalline Si solar cells. In this study three different anode materials (Co-Cr, Co-Cr-RuO2, and Ti-RuO2) and cathodes (Pt, Ni, and Cu) were tested for water splitting in an electrolyzer biased by double junction a-Si solar cell.