Self-Heating Graphene Oxide Composite Membranes for Desalination via Photothermal Membrane Distillation

Oct 3, 2026

Develop stable, scalable self-heating membranes for photothermal membrane distillation by combining graphene oxide’s high light-to-heat conversion with polyvinyl alcohol’s hydrophilicity. Janus composites with a GO-loaded PVA hydrogel coating on a porous PVDF support deliver localized light-driven heating and scaling resistance, while the hydrophobic substrate improves wetting resistance and supports evaporation under thermal gradients. A 190% flux increase with 99.99% salt rejection is achieved using 1-sun irradiation on 35 g L−1 NaCl, reaching ~70% conversion efficiency. CFD modeling quantifies temperature polarization across the module (TPC 0.8–1.2, light ON) and highlights tradeoffs between solution velocity and GO loading for desalination performance.

LanguageEnglish

CategoryResearch & Report

FormatPDF

Pages13

Reading Time33 min

AccessFree to download

Introduction

Context: global freshwater scarcity

Main desalination approaches and limitations

Membrane distillation and practical challenges

Role of temperature polarization and energy considerations

Advanced Functional Materials [www.afm-journal.de](www.afm-journal.de) RESEARCH ARTICLE Self-Heating Graphene Oxide Composite Membranes for Desalination via Photothermal Membrane Distillation Michela Romeo1 Elvira Pantuso1 Daniela Ricca1 Enrica Fontananova1 Evangelos P. Kouvelos2 Giuseppe Prenesti3 Alessio Caravella3 Andreas A. Sapalidis2 Gianluca Di Profio1 1 Istituto Per La Tecnologia delle Membrane (ITM), Consiglio Nazionale delle Ricerche (CNR), Rende, Italy 2 Institute of Nanoscience and Nanotechnology, National Centre for Scientific Research “Demokritos”, Athens, Greece 3 Department of Computer Engineering, Modelling, Electronics and Systems Engineering (DIMES), University of Calabria, Rende, Italy Correspondence: Gianluca Di Profio (g.diprofio@itm.cnr.it) Received: 31 October 2025 Revised: 5 February 2026 Accepted: 6 February 2026 Keywords: graphene oxide nanosheets | light to heat conversion | photothermal membrane distillation | self-heating membranes | water bankruptcy | water desalination ABSTRACT In this work, we develop a simple and scalable fabrication method for the preparation of stable and efficient self-heating membranes that combine the excellent photothermal conversion efficiency of graphene oxide (GO) and the hydrophilic properties of polyvinyl alcohol (PVA) for photothermal membrane distillation (PMD) applications. Our results demonstrated that Janus composite membranes comprising a thin layer of GO-loaded PVA hydrogel on a porous polyvinylidene fluoride (PVDF) support can offer a dual advantage: the hydrophilic GO-loaded hydrogel provides localized heating under light irradiation and resistance to scaling, while the hydrophobic substrate offers excellent wetting resistance and allows water evaporation under thermal gradients. As a result, a 190% flux increase with 99.99% salt rejection was achieved for a 35 g L−1 NaCl feed solution under 1 sun irradiation with 2 wt.% GO-filled composites, achieving a photothermal conversion efficiency of 70% and a specific thermal energy consumption approximately 25% lower than the latent heat of evaporation of water at the operating temperature. Detailed computational fluid dynamics (CFD) simulations allowed us to evaluate the thermal profiles across the membrane module and calculate the temperature polarization coefficient (TPC) that ranged from 0.8 to 1.2 for the light ON-state. Our results also demonstrated the fundamental dependence of process performance on solution velocity and GO loading, which establishes a key tradeoff for the efficient applicability of this technology to water desalination. 1 Introduction In the era of global water bankruptcy [1], freshwater can no longer be considered a renewable natural resource given the current excessive water stress caused by population growth, climate change, and intense industrial activities that are causing water shortages in ever larger areas of the planet [2, 3] . Therefore, ongoing research efforts are focused on the development of environmentally and economically sustainable technologies for water purification and desalination, which have become essential for increasing freshwater supply in the near future [4] . The most widely used desalination technology today is reverse osmosis (RO), known for its energy efficiency and scalability compared to traditional thermal methods such as multi-stage flash evaporation (MSF) and multi-effect distillation (MED) [5] . | Michela Romeo and Elvira Pantuso contributed equally to this work.
| | --- | | © 2026 Wiley-VCH GmbH | Advanced Functional Materials, 2026; 36:e29125 1 of 13 [https://doi.org/10.1002/adfm.202529125](https://doi.org/10.1002/adfm.202529125) However, this technology suffers from several limitations, such as the high (electrical) pumping energy (50–60 bar) [6] required for water permeation through dense RO membranes, and the serious ecological impact of large amounts of brine if released in the environme

FAQs

What membranes are developed for desalination in this study?

Stable self-heating membranes are built by integrating graphene oxide with polyvinyl alcohol to enable photothermal membrane distillation, using a Janus structure with a GO-loaded PVA hydrogel on a porous PVDF support.

How do the composite membrane components contribute to performance?

The GO-loaded hydrophilic hydrogel provides localized heating under light and resists scaling, while the hydrophobic PVDF substrate offers strong wetting resistance and facilitates evaporation under thermal gradients.

What quantitative desalination results and simulations are reported?

Under 1 sun irradiation, a 190% flux increase with 99.99% salt rejection is reported for 35 g L−1 NaCl, with ~70% photothermal conversion efficiency. CFD simulations estimate temperature polarization coefficient values ranging from 0.8 to 1.2 in the light ON state.

Oct 3, 2026

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