Quinoxaline‐6,7‐dicarboxylate‐based Photothermal Polymers Inspired Multifunctional Hydrogels for High‐Efficient Solar‐Driven Water Purification

Why It Matters

Coupling high‑efficiency solar desalination with on‑site electricity generation provides a compact, off‑grid solution for water‑energy challenges in remote regions.

Key Takeaways

• Record 10.18 kg m⁻² h⁻¹ water production
• Photothermal efficiency reaches 26.71 % under 1 sun
• Generates 55 mV electricity while evaporating
• Hydrogel stable over multiple cycles
• Portable system removes contaminants effectively

Pulse Analysis

Solar‑driven water purification has emerged as a promising route to address global freshwater scarcity, yet most technologies struggle to balance high evaporation rates with durability and contaminant removal. Traditional inorganic photothermal materials often require complex fabrication or suffer from limited light absorption, while organic systems have lagged behind in efficiency. By engineering the electronic structure of diketopyrrolopyrrole‑based polymers and incorporating strong electron‑withdrawing benzo‑thiadiazole units, the new PDPP‑SeQ polymer extends absorption into the near‑infrared and suppresses radiative losses, achieving a conversion efficiency of 26.71 % under one sun.

The integration of PDPP‑SeQ micelles into a polyethyleneimine/polyvinyl alcohol matrix creates a multifunctional hydrogel that not only maximizes solar‑thermal conversion but also supports simultaneous electricity generation. The reported evaporation rate of 10.18 kg m⁻² h⁻¹ surpasses previous organic photothermal benchmarks, while the 55 mV electrical output demonstrates the feasibility of harvesting low‑grade solar energy for auxiliary power needs. Importantly, the hydrogel maintains performance over repeated cycles, indicating robust thermal stability and resistance to fouling—critical factors for real‑world deployment.

From a market perspective, the SAG‑Se platform offers a portable, plug‑and‑play solution for off‑grid communities, disaster relief zones, and military field operations where both clean water and modest power are essential. Its dual‑functionality reduces the need for separate desalination and power infrastructure, potentially lowering capital costs and simplifying logistics. Future research can expand the polymer library to tune voltage output, explore scalable manufacturing, and integrate additional treatment modalities such as antimicrobial agents, positioning photothermal hydrogels as a cornerstone of next‑generation water‑energy systems.