Low‐Thermal‐Budget Doping of 2D Materials in Ambient Air Exemplified by Synthesis of Boron‐Doped Reduced Graphene Oxide

• Published in: Advanced science Vol. 7; no. 7; pp. 1903318 - n/a
• Main Authors: Cha, Jun‐Hwe, Kim, Dong‐Ha, Park, Cheolmin, Choi, Seon‐Jin, Jang, Ji‐Soo, Yang, Sang Yoon, Kim, Il‐Doo, Choi, Sung‐Yool
• Format: Journal Article
• Language: English
• Published: Germany John Wiley & Sons, Inc 01.04.2020; John Wiley and Sons Inc; Wiley
• Subjects: Annealing; Energy; flash irradiation; gas sensors; Glass substrates; Graphene; graphene oxide; Light; low‐thermal‐budget doping; Morphology; Nanomaterials; Nanowires; Sensors; graphene oxide; low‐thermal‐budget doping; flash irradiation; gas sensors
• ISSN: 2198-3844; 2198-3844
• DOI: 10.1002/advs.201903318

Graphene oxide (GO) doping and reduction allow for physicochemical property modification to suit practical application needs. Herein, the challenge of simultaneous low‐thermal‐budget heteroatom doping of GO and its reduction in ambient air is addressed through the synthesis of B‐doped reduced GO (B@rGO) by flash irradiation of boric acid loaded onto a GO support with intense pulsed light (IPL). The effects of light power and number of shots on the in‐depth sequential doping and reduction mechanisms are investigated by ex situ X‐ray photoelectron spectroscopy and direct millisecond‐scale temperature measurements (temperature >1600 °C, < 10‐millisecond duration, ramping rate of 5.3 × 105 °C s−1). Single‐flash IPL allows the large‐scale synthesis of substantially doped B@rGO (≈3.60 at% B) to be realized with a thermal budget 106‐fold lower than that of conventional thermal methods, and the prepared material with abundant B active sites is employed for highly sensitive and selective room‐temperature NO2 sensing. Thus, this work showcases the great potential of optical annealing for millisecond‐scale ultrafast reduction and heteroatom doping of GO in ambient air, which allows the tuning of multiple physicochemical GO properties. Simultaneous heteroatom doping and reduction of graphene oxide (GO) in ambient air by a low‐thermal‐budget process is carried out through single‐shot irradiation using a Xe flash lamp. Compared to pristine reduced GO (rGO), B‐doped rGO features improve NO2 sensing performance (better response and reversibility), especially in a highly humid atmosphere.