Computer-based study on the sensing of formaldehyde using gold-decorated biphenylene monolayers

A first-principles DFT investigation was conducted to study the sensing of formaldehyde (CH₂O) via pure biphenylene monolayer (PBPML) and gold-decorated biphenylene monolayer (Au-BPML) monolayer. The PBPML exhibited superior adhesion of CH₂O molecule in comparison with other reported 2D materials, but it physiosorbed onto the PBPML with the adhesion energy of −0.409 eV. However, decorating the Au atom significantly improved the CH₂O adhesion capacity of BP and caused a notable change in its electronic attributes. The Au-BPML can be a suitable sensor for CH₂O with structural steadiness at ambient temperature, a reasonable charge transfer of 0.947 e, adhesion energy of −0.836 eV, and the recovery time of 1.03 s at 300 K. This study highlights the suitability of Au-BPML for CH₂O sensing and its practical application. It also presents a new approach for the design and development of efficient sensors for biomolecule.