Biomass-derived carbon deposited TiO2 nanotube photocatalysts for enhanced hydrogen production

Shaeel Ahmed Althabaiti; Zaheer Khan; Maqsood Ahmad Malik; Salem Mohamed Bawaked; Soad Zahir Al-Sheheri; Mohamed Mokhtar; Sharf Ilahi Siddiqui; Katabathini Narasimharao

doi:10.1039/d3na00211j

Biomass-derived carbon deposited TiO₂ nanotube photocatalysts for enhanced hydrogen production

Nanoscale Adv. 2023 Jun 23;5(14):3671-3683. doi: 10.1039/d3na00211j. eCollection 2023 Jul 11.

Authors

Shaeel Ahmed Althabaiti¹, Zaheer Khan¹, Maqsood Ahmad Malik², Salem Mohamed Bawaked¹, Soad Zahir Al-Sheheri¹, Mohamed Mokhtar¹, Sharf Ilahi Siddiqui³, Katabathini Narasimharao¹

Affiliations

¹ Chemistry Department, Faculty of Science, King Abdulaziz University P.O. Box 80203 Jeddah 21589 Saudi Arabia nkatabathini@kau.edu.sa.
² Department of Chemistry, Faculty of Natural Sciences, Jamia Millia Islamia New Delhi 110025 India mamalik@jmi.ac.in.
³ Department of Chemistry, Ramjas College, University of Delhi Delhi-07 India.

Abstract

In this study, titanium oxide nanotubes (TiO₂NTs) were deposited on the surface of activated carbon (AC) by varying the wt% of AC. The physicochemical properties of synthesized TiO₂NTs-AC nanocomposites were analysed by various characterization techniques such as XRD, FT-IR, Raman, DRUV-vis, HR-TEM, XPS, PL, and N₂ physisorption. The FT-IR, EDX, and XPS analyses proved the existence of interaction between AC and TiO₂NTs. This study found that as the content of AC increases, the surface area and pore volume increase while the energy bandgap decreases. The TiO₂NTs-AC nanocomposite with 40% AC exhibited a surface area of 291 m² g^-1, pore volume of 0.045 cm³ g^-1 and half pore width = 8.4 Å and had a wide band gap energy (3.15 eV). In addition, the photocatalytic application of the prepared nanocomposites for photocatalytic H₂ production was investigated. The H₂ was produced via photo-reforming in the presence of a sacrificial agent (methanol) under sunlight irradiation. It was found that the prepared TiO₂NTs-AC nanocomposite with 40% AC acted as an efficient photocatalyst for aqueous-methanol reforming under various optimization conditions. Approximately 18 000 μmol^-1 hydrogen gas was produced via aqueous-methanol reforming under optimized conditions (catalyst dose = 100 mg, temperature = 25 °C, time = 12 hours, vol. of methanol = 20% (v/v), and pH = 7). The reusability of the TiO₂NTs-AC nanocomposite was also investigated for 5 consecutive cycles, and the results suggested only a slight decline in efficiency even after the fifth cycle. This study demonstrates the ability of an activated carbon deposited TiO₂NT catalyst to produce hydrogen effectively under sunlight.