TY - JOUR
T1 - Tandem Cuprous Oxide/Silicon Microwire Hydrogen-Evolving Photocathode with Photovoltage Exceeding 1.3 v
AU - Vijselaar, Wouter
AU - Kunturu, Pramod Patil
AU - Moehl, Thomas
AU - Tilley, S. David
AU - Huskens, Jurriaan
N1 - ACS deal
PY - 2019/9/13
Y1 - 2019/9/13
N2 - Large research efforts have been devoted to optimizing the output of earth-abundant photoabsorbers in solar-to-fuel (S2F) devices. Here, we report a Cu2O/Ga2O3 heterojunction/Si microwire photocathode with an underlying buried radial Si p-n junction, which achieves efficient light harvesting across the visible spectrum to over 600 nm, reaching an external quantum yield for hydrogen generation close to 80%, with a photocurrent onset above +1.35 V vs RHE, a photocurrent density of ∼10 mA/cm2 at 0 V vs RHE, and an ideal regenerative efficiency of 5.51%. We show step-by-step the effects of every photocathode design element (i.e., Si p-n junction, Cu2O layer thickness, microwire length, microwire pitch, etc.) on the overall efficiency of our final microwire Si/Cu2O photocathode by comparing every addition to a baseline Cu2O photocathode. Lastly, we show a stable operation exceeding 200 h at a bias potential of +1.0 V vs RHE, with an average current density of 4.5 mA/cm2
AB - Large research efforts have been devoted to optimizing the output of earth-abundant photoabsorbers in solar-to-fuel (S2F) devices. Here, we report a Cu2O/Ga2O3 heterojunction/Si microwire photocathode with an underlying buried radial Si p-n junction, which achieves efficient light harvesting across the visible spectrum to over 600 nm, reaching an external quantum yield for hydrogen generation close to 80%, with a photocurrent onset above +1.35 V vs RHE, a photocurrent density of ∼10 mA/cm2 at 0 V vs RHE, and an ideal regenerative efficiency of 5.51%. We show step-by-step the effects of every photocathode design element (i.e., Si p-n junction, Cu2O layer thickness, microwire length, microwire pitch, etc.) on the overall efficiency of our final microwire Si/Cu2O photocathode by comparing every addition to a baseline Cu2O photocathode. Lastly, we show a stable operation exceeding 200 h at a bias potential of +1.0 V vs RHE, with an average current density of 4.5 mA/cm2
KW - UT-Hybrid-D
UR - http://www.scopus.com/inward/record.url?scp=85072584450&partnerID=8YFLogxK
U2 - 10.1021/acsenergylett.9b01402
DO - 10.1021/acsenergylett.9b01402
M3 - Article
AN - SCOPUS:85072584450
SN - 2380-8195
VL - 4
SP - 2287
EP - 2294
JO - ACS Energy Letters
JF - ACS Energy Letters
IS - 9
ER -
