Park, Jaemin Rhee, Jin Hyeong Kim, Youngeun Kim, Min Jae Park, Junbeom Barma, Sunil V. Seok, Jun Ho Lee, Sang Uck Shin, Eul-Yong Kim, Dong Su Cho, Hyung Koun Kim, Jin Young Jo, Sae Byeok Son, Hae Jung Yang, Wooseok 2025-04-25T08:01:24Z 2025-04-25T08:01:24Z 2025-04-25 2025-06 https://pubs.kist.re.kr/handle/201004/152345 The realization of practical solar hydrogen production relies on the development of efficient devices with nontoxic and low-cost materials. Since the predominant contributors for the performance and cost are the catalyst and the light absorber, it is imperative to develop cost-effective catalysts and absorbers that are compatible with each other for achieving high performance. In this study, a 10% efficient solar-to-hydrogen conversion device was developed through the meticulous integration of low-cost Ni Heazlewoodite-based catalysts for the hydrogen evolution reaction (HER) and ternary bulk heterojunction organic semiconductor (OS)-based light absorbers. Se-incorporated Ni3S2 was synthesized using a simple one-step hydrothermal method, which demonstrated a low overpotential and Tafel slope, indicating superior HER activity compared to Ni₃S₂. The theoretical calculation results validate the enhanced HER performance of the Se-incorporated Ni₃S₂ catalyst in alkaline electrolytes. The ternary phase organic light absorber is designed to generate tailored photovoltage and maximized photocurrent, resulting in a photocurrent density of 8.24 mA cm−2 under unbiased conditions, which corresponds to 10% solar to hydrogen conversion. Low-temperature photoluminescence spectroscopy results revealed that the enhanced photocurrent density originates from a reduction in both phonon- and vibration-induced inter- and intramolecular non-radiative decay. Our results establish a new benchmark for the emerging OS-based efficient solar hydrogen production based on nontoxic and cost-effective materials. English Wiley 10% Efficient Solar-to-Hydrogen Conversion via Ternary-Phase Organic Light Absorbers With Ni Heazlewoodite Electrocatalysts Article 10.1002/cey2.706 1 Carbon Energy, v.7, no.6 Carbon Energy 7 6 Y scie scopus 001458079800001 2-s2.0-105001934360 Chemistry, Physical Energy & Fuels Nanoscience & Nanotechnology Materials Science, Multidisciplinary Chemistry Energy & Fuels Science & Technology - Other Topics Materials Science Article COST SB2SE3 PHOTOCATHODES UNASSISTED SOLAR WATER EVOLUTION CATALYSTS CELLS hydrogen nickel sulfide organic semiconductor photoelectrochemical water splitting electrocatalyst