Direct‐Laser‐Writing of Metal Sulfide‐Graphene Nanocomposite Photoelectrode toward Sensitive Photoelectrochemical Sensing

• Published in: Advanced functional materials 2019-09, Vol.29 (38), p.n/a
• Main Authors: Ge, Lei, Hong, Qing, Li, Hui, Liu, Changchun, Li, Feng
• Format: Article
• Language: English
• Subjects: Carbon dioxide; Carbon dioxide lasers; Carbothermic reactions; Coordination compounds; Copper; copper ion; Crystallization; Glass; Graphene; hybrid nanocomposite; Indium tin oxides; Lasers; laser‐induced graphene; Materials science; metal sulfide; Nanocomposites; Nanocrystals; Photoelectric effect; Photoelectric emission; photoelectrochemical sensing; Polyethersulfones; Selectivity; Tin oxides
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.201904000

Here, a facile approach for the in situ fabrication of metal sulfide (MS)‐graphene (G) nanocomposite, CdS‐G and PbS‐G, on indium−tin oxide (ITO) glass is demonstrated using a simple and scalable direct‐laser‐writing method in ambient air. Through the CO2 laser irradiation of a metal‐complex‐containing polyethersulfone layer on ITO glass, both the crystallization of laser‐induced MS (LIMS) and the formation of laser‐induced graphene (LIG) are synchronously achieved in one step, giving rise to a laser‐induced MS‐G nanocomposite photoelectrode, denoted as LI‐MS‐G@ITO. In such a laser‐scribing process, polyethersulfone not only acts as the carbon source to grow LIG but also provides an in situ source of S2− to produce LIMS with the aids of carbothermic reduction of sulfur element in polyethersulfone. The obtained LI‐MS‐G@ITO inherits the porous network architecture of polyethersulfone‐derived LIG, in which the LIMS nanocrystals uniformly decorate the multilayered graphene sheets with good dispersion, presenting a fast and stable photocurrent response with high reproducibility, which, as a proof‐of‐concept, further facilitates the use of a LI‐CdS‐G@ITO photoanode as an efficient transducer for photoelectrochemical detection of Cu2+ with high sensitivity and selectivity. This work can offer a universal and versatile protocol for the in situ and synchronous fabrication of novel MS‐G nanocomposites for sensitive photoelectrochemical analysis. Direct laser writing of a metal sulfide‐graphene nanocomposite on indium‐tin oxide glass is successfully demonstrated to fabricate unique photoelectrodes with a rapid and stable photocurrent response under visible light irradiation. Both the in situ generation of laser‐induced metal sulfide and the formation of laser‐induced graphene are synchronously achieved in one step with the aid of carbothermic reduction of sulfur in polyethersulfone.