CuO/TiO2/ZnO NPs Anchored Hydrogen Exfoliated Graphene: To Comprehend the Role of Graphene in Catalytic Reduction of p-Nitrophenol

Meerambika Behera; Fatimah Othman Alqahtani; Sankha Chakrabortty; Jayato Nayak; Shirsendu Banerjee; Ramesh Kumar; Byong-Hun Jeon; Suraj K Tripathy

doi:10.1021/acsomega.3c03859

CuO/TiO₂/ZnO NPs Anchored Hydrogen Exfoliated Graphene: To Comprehend the Role of Graphene in Catalytic Reduction of p-Nitrophenol

ACS Omega. 2023 Nov 1;8(45):42164-42176. doi: 10.1021/acsomega.3c03859. eCollection 2023 Nov 14.

Authors

Meerambika Behera¹, Fatimah Othman Alqahtani², Sankha Chakrabortty¹, Jayato Nayak³, Shirsendu Banerjee¹, Ramesh Kumar⁴, Byong-Hun Jeon⁴, Suraj K Tripathy¹

Affiliations

¹ School of Chemical Technology, Kalinga Institute of Industrial Technology, Bhubaneswar, Odisha 751024, India.
² Department of Chemistry, College of Science, King Faisal University, P.O. Box 380, Al-Ahsa 31982, Saudi Arabia.
³ Centre for Life Science, Mahindra University, Bahadurpally, Jeedimetla, Hyderabad, Telangana 500043, India.
⁴ Department of Earth Resources & Environmental Engineering, Hanyang University, 222-Wangsimni-ro, Seongdong-gu, Seoul 04763, Republic of Korea.

Abstract

The present study deals with sonochemically in situ synthesis of a novel functional catalyst using hydrogen exfoliated graphene (HEG) supported titanium dioxide (TiO₂) and copper sulfate (CuSO₄) doped with zinc oxide (ZnO) (abbreviated as Ti/Cu/Zn-HEG). The synthesis of the Ti/Cu/Zn-HEG nanocomposite (NCs) catalyst was confirmed through its characterizations by XRD, SEM-EDX, TEM, XPS, FTIR, and BET methods. It was assessed for catalytic conversion of a model aromatic compound para-nitrophenol (p-NP) in an aqueous solution. The p-NP is a nitroaromatic compound that has a toxic and mutagenic effect. Its removal from the water system is necessary to protect the environment and living being. The newly synthesized Ti/Cu/Zn-HEG NCs were applied for their higher stability and catalytic activity as a potential candidate for reducing p-NP in practice. The operating parameters, such as p-NP concentration, catalyst dosage, and operating time were optimized for 150 ppm, 400 ppm, and 10 min through response surface methodology (RSM) in Design-Expert software to obtain the maximum reduction p-NP up to 98.4% at its normal pH of 7.1 against the controls (using HEG, Ti/Cu-HEG, and Zn-HEG). Analysis of variance of the response suggested the regression equation to be significant for the process with a major impact on catalyst concentration and operating time. The model prediction data (from RSM) and experimental data were corroborated well as reflected through model's low relative error (RE < 0.10), high regression coefficient (R² > 0.97), and Willmott d-index (d_will-index > 0.95) values.