SUPPLEMENTARY INFORMATION D0:10.1038/NMAT3228 (1)Advancing and receding contact angles In addition to the sessile drop (as in Fig.2a in manuscript),we also studied the wetting transparency with respect to the advancing and receding contact angles.Typical results are shown below for baseline silicon and silicon with monolayer graphene coating.The measured advancing contact angle for silicon(~36 deg:Fig.Sla)was very similar to monolayer graphene coated silicon(~35 deg:Fig.SIb).Similarly the receding water contact angle on silicon(~30 deg: Fig.S1c)was also similar to that of monolayer graphene coated silicon(~31 deg:Fig.S1d).The difference between the advancing and receding contact angles(i.e.the contact angle hysteresis) for the samples were in the range of 4 to 6 degrees. (a) (b) Figure S1:Advancing water front for baseline silicon(a)and the monolayer graphene coated silicon (b).Corresponding images for the receding water front for silicon(c)and monolayer graphene coated silicon(d). 2 NATURE MATERIALS www.nature.com/naturematerials 2012 Macmillan Publishers Limited.All rights reserved.(1) Advancing and receding contact angles In addition to the sessile drop (as in Fig. 2a in manuscript), we also studied the wetting transparency with respect to the advancing and receding contact angles. Typical results are shown below for baseline silicon and silicon with monolayer graphene coating. The measured advancing contact angle for silicon (~36 deg: Fig. S1a) was very similar to monolayer graphene coated silicon (~35 deg: Fig. S1b). Similarly the receding water contact angle on silicon (~30 deg: Fig. S1c) was also similar to that of monolayer graphene coated silicon (~31 deg: Fig. S1d). The difference between the advancing and receding contact angles (i.e. the contact angle hysteresis) for the samples were in the range of 4 to 6 degrees. (a) (b) (c) (d) Figure S1: Advancing water front for baseline silicon (a) and the monolayer graphene coated silicon (b). Corresponding images for the receding water front for silicon (c) and monolayer graphene coated silicon (d). 2 NATURE MATERIALS | www.nature.com/naturematerials SUPPLEMENTARY INFORMATION DOI: 10.1038/NMAT3228 © 2012 Macmillan Publishers Limited. All rights reserved