Solar-Driven Ultrafast Production of Gram-Per-Litre Level Hydrogen Peroxide With 2.74% Solar-to-Chemical Efficiency via Synergistic Photothermal Catalysis by W-Based Amorphous Metal-Organic Polymers.

Abstract

Hydrogen peroxide (H₂O₂) is a critical industrial chemical traditionally produced via the energy-intensive anthraquinone process. Here, we report a low-cost (<$0.6/g), hydroxyl-functionalized metal-organic polymer (MIL-2OH-W) featuring abundant undercoordinated [WO₆]⁶ ^- centers for solar-driven H₂O₂ production. MIL-2OH-W achieves a record production rate of 11.25 mmol·g^- ¹·h^- ¹ in the first 10 min and becomes saturated to 3 mmol·g^- ¹·h^- ¹ in 1 h, reaching a concentration of 1.02 g·L^- ¹ (30 mmol·L^- ¹) with a 2.74% solar-to-chemical efficiency under mild conditions (40°C). Mechanistic studies from in-situ transient absorption, in-situ infrared, in-situ electron paramagnetic resonance and density functional theory reveal a synergistic photothermal pathway, where aromatic hydroxyl linkers mimic anthraquinone-like redox cycling, stabilize radical intermediates, and accelerate oxygen reduction. The catalyst exhibits exceptional stability (>40 days) and scalability, aligning with the United Nations decarbonization goals. This work provides a blueprint for sustainable H₂O₂ synthesis by integrating photothermal catalysis with waste-heat utilization.