Toward Practical Photoelectrochemical Fuel Production

Photoelectrochemical water splitting technology, mimicking natural photosynthesis, stands out as one of the most promising technologies for solar hydrogen production. For this technology to become commercially viable, it must meet three critical criteria: efficiency, stability, and scalability. Notably, the solar-to-hydrogen conversion (STH) efficiency must reach at least 10%. Two primary strategies are key to achieving these goals. The first strategy involves enhancing the efficiency of stable inorganic materials such as TiO₂, Fe₂O₃, and BiVO₄. The second strategy focuses on stabilizing high-efficiency materials. In this presentation, I will explore both approaches, with particular emphasis on the latter. I will introduce methods for stabilizing efficient organic or inorganic-organic hybrid-based semiconductors possessing superior charge-transfer characteristics, lower band gap, and tunable energy levels. Moreover, I will discuss several strategies for scaling up photoelectrodes while minimizing losses in STH efficiency. Finally, I will extend these approaches to the production of other solar fuels, such as hydrogen peroxide (H₂O₂) and ammonia (NH₃).<br/><br/><b><i>References</i></b><br/>J.-W. Jang <i>et al.</i> “Photoelectrochemical water splitting with high performance and stable Organic based photoanode.” <i><b>Nat. Commun</b></i>. 2020<i>, </i><i>11, </i>5509<br/>J.-W. Jang <i>et al.</i> “Bias-free solar hydrogen production at 19.8 mA cm⁻² using perovskite photocathode and lignocellulosic biomass.” <b><i>Nat. Commun. </i></b>2022, <i>13</i><i>, </i>5709<br/>J.-W. Jang <i>et al. </i>“All-perovskite-based unassisted photoelectrochemical water splitting system for efficient, stable, and scalable solar hydrogen production.”<b> <i>Nature Energy</i></b> 2024, <i>9</i>, 272-284<br/>J.-W. Jang <i>et al.</i> “Direct propylene epoxidation with oxygen by photo-electro-heterogeneous catalytic system.” <b><i>Nature</i></b> <b><i>Catalysis</i></b> 2022, <i>5</i>,37<br/>J.-W. Jang <i>et al.</i> “Bias-free high-performance solar NH₃ production by perovskite-based photocathode and <i>in situ</i> valorization of glycerol.” <b><i>Nature Catalysis</i></b> 2024, <i>7</i>, 510–521