The metal-free porous organic catalyst was developed by the researchers from the Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), along with other institutions.
| Photo Credit: Freepik

In an interdisciplinary study, researchers from the Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), along with other institutions, have developed a novel, cost-effective, metal-free porous organic catalyst for efficient Hydrogen fuel production by harvesting mechanical energy.

According to the Department of Science and Technology, in order to reduce global warming and the related impact of fossil fuels, transition towards sustainable alternatives based on renewable energy becomes increasingly critical.

Game-changing source

“Green hydrogen (H₂) fuel has emerged as a game-changing renewable and clean-burning energy source, which generates no direct carbon emissions and only water as a by-product when used in fuel cells,” it said.

Professor Tapas K. Maji  from the Chemistry and Physics of Materials Unit at JNCASR and his research team have developed a metal-free donor-acceptor based covalent-organic framework (COF) for piezocatalytic water splitting.

This study published in Advanced Functional Materials demonstrates a Covalent organic framework (COF) built from imide linkages between organic donor molecule tris(4-aminophenyl)amine (TAPA) and acceptor molecule pyromellitic dianhydride (PDA) acceptor exhibiting unique ferrielectric (FiE) ordering, which showed efficient piezocatalytic activity for water splitting to produce H2.

“This discovery breaks the traditional notion of solely employing heavy or transition metal-based ferroelectric (FE) materials as piezocatalysts for catalyzing water splitting reaction,” the department stated.

Using a simple donor molecule like TAPA and an acceptor molecule like PDA, Prof. Maji and his research team have built a COF system that has strong charge transfer properties, which creates dipoles (separation between positive and negative charges).

Instability in structure

This causes instability in the lattice structure, leading to FiE ordering. These FiE dipoles interact with flexible twisting molecular motion in the material, making them responsive to mechanical pressure. As a result, the material can generate electron-hole pairs when mechanically stimulated, making it a highly efficient piezocatalyst for water splitting for H2 production. The team comprises four other researchers from JNCASR: Adrija Ghosh, Surabhi Menon, Dr. Sandip Biswas and Dr. Anupam Dey.

Apart from JNCASR, Dr. Supriya Sahoo and Prof. Ramamoorthy Boomishankar from  Indian Institute of Science Education and Research, Pune and Prof. Jan K. Zaręba from Wrocław University of Science and Technology, Poland made important contributions to the present interdisciplinary study.