W@Ag dendrites as efficient and durable electrocatalyst for solar-to-CO conversion using scalable photovoltaic-electrochemical system

Photovoltaic-Powered Electrochemical CO2 Reduction: Benchmarking against the Theoretical Limit

“…Results show that the current density and voltage are stable at ∼16 mA cm –2 and 1.7 V, respectively, as designed; the Faradaic efficiency of CO is 91.2%. The corresponding STC efficiency is 21.3%, which represents the state-of-the-art in the literature − (see Figure and Table S1).…”

“…Another approach being explored is the individual CO 2 reduction to CO and water splitting to produce hydrogen, using a downstream Fischer–Tropsch process to make the desired hydrocarbons. , Since solar CO is the intermediate of these two approaches, photovoltaic-powered electrochemical (PEC ,, ) CO 2 reduction to CO is the central technology for both of them. Despite efforts toward the development of efficient and selective catalysts, − the most recently reported solar-to-chemical (STC) energy conversion efficiency was still below 20% . We believe it is the right time to address the fundamental issue, i.e., how close PEC CO 2 reduction can approach the theoretical limit.…”

“…In this work, a benchmarking device for photovoltaic-powered electrochemical CO 2 reduction (without a DC/DC converter) was built, and our experimentally demonstrated STC efficiency was benchmarked against the theoretical limit for the first time to the best of our knowledge. − The STC efficiency was also compared to the STH efficiency based on the same photoabsorber both experimentally and theoretically so that the potential of the solar fuel approach with either solar CO as the intermediate, or both solar CO and hydrogen as the intermediates, can be fully explored.…”

Operandocharacterization of continuous flow CO2electrolyzers: current status and future prospects

“…Silver is the state-of-the-art catalyst for CO 2 reduction to CO, but interestingly only a couple of studies aimed at its operando XAS investigation at high current densities. 115,122 A sputtered Ag catalyst was studied in a microfluidic flow cell at current densities between 1 and 200 mA cm −2 . 115 An increase in crystallite size and a decrease in Ag–Ag distance during CO 2 RR were found, compared to the as-prepared ( ex situ ) sample.…”

“…X-ray absorption spectroscopy is currently the most widely applied operando spectroscopy to study the evolution of catalyst structure during CO 2 RR under high current density conditions. 18,113,115,118–123 Because of its great compatibility with flow cell designs, the operando measurement requires only minor cell modifications (Fig. 5).…”