Small 2013, 9:1686–1690.CrossRef Competing interests The authors declare that they have no competing interests. Authors’ contributions WW carried out the immunoassays, participated in the design of the study, drafted the manuscript, and performed the statistical analysis. ZL carried out the materials study, participated in the design of the study, and drafted the

manuscript. JD carried out the cell culture. CW and YF provided the graphene, participated in the design of the study, and helped to draft the manuscript. X-DY conceived of the study, participated in its design and coordination, and helped to draft the manuscript. All authors read and approved the final manuscript.”
“Background Transparent electrodes

are a required component of many buy Alvocidib devices such as organic solar cells, electronic displays, and touch screens. The most commonly used transparent conductor is indium tin oxide selleck compound (ITO). ITO, however, is expensive, not suitable for flexible applications, and requires sputtering, high temperatures, and vacuum for its deposition. Several materials have been proposed to replace ITO such as graphene [1], carbon nanotubes [2, 3], and copper [4, 5] and silver nanowires [6–8]. Of these, silver nanowire electrodes have been identified as the lead alternative because they have the lowest sheet S3I-201 in vitro resistance at a given transparency [9–11]. Not only can silver nanowire electrodes provide the same sheet resistance and transparency as ITO, but they are also highly flexible [12, 13] and inexpensive [11], and their fabrication is compatible with

roll-to-roll processes. In spite of all the advantages Celastrol of nanowire electrodes, there are certain issues that need to be addressed before their widespread use in devices. One of these most important issues is their surface roughness. Because there are typically junctions on an electrode where three or more nanowires are stacked on top of one another, maximum peak-to-valley values can reach three times the diameter of the nanowires or more [12, 14]. Nanowires with diameters of 90 nm are commonly used, and so, these electrodes have peak-to-valley values around or exceeding 270 nm. This is problematic for many devices, especially ones that consist of thin layers. In organic electronic devices, for example, the low electron mobility and fast recombination times require organic layers to be less than 100-nm thick (typically 40 to 80 nm depending on the device and materials used) [15, 16]. Several reports where silver nanowire electrodes have been used in organic solar cells have reported lower efficiencies than equivalent devices built on ITO. The rough surface of the nanowire electrodes causes a lower shunt resistance, which increases the dark current and hinders the efficiency of the solar cells [17–19].