10% Efficient Solar‐to‐Hydrogen Conversion via Ternary‐Phase Organic Light Absorbers With Ni Heazlewoodite Electrocatalysts

• DOI: 10.1002/cey2.706
• Publication Date: 2025-04-04T08:45:24Z
• Authors: Jaemin Park; Jin Hyeong Rhee; Youngeun Kim; Min Jae Kim; Junbeom Park; Sunil V. Barma; Jun Ho Seok; Sang Uck Lee; Eul‐Yong Shin; Dong Su Kim; Hyung Koun Cho; Jin Young Kim; Sae Byeok Jo; Hae Jung Son; Wooseok Yang

ABSTRACT The realization of practical solar hydrogen production relies on the development efficient devices with nontoxic and low‐cost materials. Since predominant contributors for performance cost are catalyst light absorber, it is imperative to develop cost‐effective catalysts absorbers that compatible each other achieving high performance. In this study, a 10% solar‐to‐hydrogen conversion device was developed through meticulous integration Ni Heazlewoodite‐based evolution reaction (HER) ternary bulk heterojunction organic semiconductor (OS)‐based absorbers. Se‐incorporated 3 S 2 synthesized using simple one‐step hydrothermal method, which demonstrated low overpotential Tafel slope, indicating superior HER activity compared Ni₃S₂. theoretical calculation results validate enhanced Ni₃S₂ in alkaline electrolytes. phase absorber designed generate tailored photovoltage maximized photocurrent, resulting photocurrent density 8.24 mA cm −2 under unbiased conditions, corresponds conversion. Low‐temperature photoluminescence spectroscopy revealed originates from reduction both phonon‐ vibration‐induced inter‐ intramolecular non‐radiative decay. Our establish new benchmark emerging OS‐based based