Highly stable and durable ZnIn2S4 nanosheets wrapped oxygen deficient blue TiO2(B) catalyst for selective CO2 photoreduction into CO and CH4

D Praveen Kumar; Khai H Do; A Putta Rangappa; Jehee Lee; Jinming Wang; Ramireddy Boppella; Madhusudana Gopannagari; K Arun Joshi Reddy; D Amaranatha Reddy; Tae Kyu Kim

doi:10.1016/j.jcis.2023.07.197

Highly stable and durable ZnIn₂S₄ nanosheets wrapped oxygen deficient blue TiO₂(B) catalyst for selective CO₂ photoreduction into CO and CH₄

J Colloid Interface Sci. 2023 Dec:651:264-272. doi: 10.1016/j.jcis.2023.07.197. Epub 2023 Jul 30.

Affiliations

¹ Department of Chemistry, Yonsei University, Seoul 03722, Republic of Korea.
² Department of Sciences, Indian Institute of Information Technology Design and Manufacturing, Kurnool 581007, Andhra Pradesh, India.
³ Department of Chemistry, Yonsei University, Seoul 03722, Republic of Korea. Electronic address: tkkim@yonsei.ac.kr.

PMID: 37542901
DOI: 10.1016/j.jcis.2023.07.197

Abstract

Developing new and highly stable efficient photocatalysts is crucial for achieving high performance and selective photocatalytic CO₂ conversion. In this paper, we designed a one-dimensional oxygen-deficient blue TiO₂(B) (BT) catalyst for improved electron mobility and visible light accessibility. In addition, hexagonal ZnIn₂S₄ (ZIS) nanosheets with a low bandgap and great visible light accessibility are employed to produce effective heterostructures with BT. The synthesized materials are tested for photocatalytic conversion of CO₂ into solar fuels (H₂, CO and CH₄). The optimized composite yields 71.6 and 10.3 μmol g^-1h^-1 of CO and CH₄, three and ten times greater than ZIS, respectively. When ZIS nanosheets are combined with a one-dimensional oxygen-deficient BT catalyst, improved electron mobility and visible light accessibility are achieved, charge carriers are effectively segregated, and the transfer process is accelerated, resulting in efficient CO₂ reduction. The photocatalytic CO₂ conversion activity of the constructed BT/ZIS heterostructures is very stable over a 10-day (240-hour) period, and CO and CH₄ production rates increase linearly with time; however, as time goes on, the rates of H₂ production decrease. Further, a five-time recycling test confirmed this, revealing essentially equal activity and selectivity throughout the experiment. As a result, CO₂ to CO and CH₄ conversion has high selectivity and longer durability. The band structure of the BT/ZIS composite is determined using Mott-Schottky measurement, diffuse reflectance spectroscopy, and valence band X-ray photoelectron spectroscopy. This research demonstrates a novel approach to investigating effective, stable, and selective photocatalytic CO₂ reduction systems for solar-to-chemical energy conversion.

Keywords: Blue TiO(2); CO(2) conversion; Nanocavity; Photocatalyst; ZnIn(2)S(4) nanosheets.