Rebounding Droplet‐Droplet Collisions on Superhydrophobic Surfaces: from the Phenomenon to Droplet Logic

When water droplets impact each other while traveling on a superhydrophobic surface, we demonstrate that they are able to rebound like billiard balls. We present elementary Boolean logic operations and a flip-flop memory based on these rebounding water droplet collisions. Furthermore, bouncing or coalescence can be easily controlled by process parameters. Thus by the controlled coalescence of reactive droplets, here using the quenching of fluorescent metal nanoclusters as a model reaction, we also demonstrate an elementary operation for programmable chemistry.

[1]  Ya-Pu Zhao,et al.  The head-on colliding process of binary liquid droplets at low velocity: high-speed photography experiments and modeling. , 2008, Journal of colloid and interface science.

[2]  I. Mahboob,et al.  Bit storage and bit flip operations in an electromechanical oscillator. , 2008, Nature nanotechnology.

[3]  N. Gershenfeld,et al.  Microfluidic Bubble Logic , 2006, Science.

[4]  Toshinori Munakata,et al.  Micro/nanofluidic computing , 2007, CACM.

[5]  Robin H. A. Ras,et al.  Fluorescent silver nanoclusters. , 2011, Nanoscale.

[6]  George M. Whitesides,et al.  Coding/Decoding and Reversibility of Droplet Trains in Microfluidic Networks , 2007, Science.

[7]  Svend Tollak Munkejord,et al.  Transition between coalescence and bouncing of droplets on a deep liquid pool , 2011 .

[8]  D. Quéré.  Wetting and Roughness , 2008 .

[9]  Michael Newton,et al.  Progess in superhydrophobic surface development. , 2008, Soft matter.

[10]  J. Rühe,et al.  Some thoughts on superhydrophobic wetting , 2009 .

[11]  Michael A. Nilsson,et al.  The effect of contact angle hysteresis on droplet coalescence and mixing. , 2011, Journal of colloid and interface science.

[12]  H. Klauk,et al.  Ultralow-power organic complementary circuits , 2007, Nature.

[13]  Andrew Adamatzky,et al.  Robust Soldier Crab Ball Gate , 2011 .

[14]  B K Jenkins,et al.  Sequential optical logic implementation. , 1984, Applied optics.

[15]  Eric Lauga,et al.  A smooth future? , 2011, Nature materials.

[16]  A. P. de Silva,et al.  Molecular logic and computing. , 2007, Nature nanotechnology.

[17]  B. Bhushan,et al.  Energy transitions in superhydrophobicity: low adhesion, easy flow and bouncing , 2008 .

[18]  Dim-Lee Kwong,et al.  Digital microfluidics: Droplet based logic gates , 2007 .

[19]  S. Bell,et al.  Remarkably simple fabrication of superhydrophobic surfaces using electroless galvanic deposition. , 2007, Angewandte Chemie.

[20]  Lei Jiang,et al.  Recent developments in bio-inspired special wettability. , 2010, Chemical Society reviews.

[21]  Magnus Berggren,et al.  Iontronics : Ionic Carriers in Organic Electronic Materials and Devices , 2010 .

[22]  J. Zou,et al.  Experimental study of a drop bouncing on a liquid surface , 2011 .

[23]  Abraham Marmur,et al.  Biological and Synthetic Self-Cleaning Surfaces , 2008 .

[24]  Chung King Law,et al.  Regimes of coalescence and separation in droplet collision , 1997, Journal of Fluid Mechanics.

[25]  Limu Wang,et al.  Microdroplet-based universal logic gates by electrorheological fluid , 2011 .

[26]  Biao Zhou,et al.  Experimental and mechanistic description of merging and bouncing in head-on binary droplet collision , 2008 .

[27]  R. Forchheimer,et al.  Towards woven logic from organic electronic fibres. , 2007, Nature materials.

[28]  Chung King Law,et al.  An experimental investigation on the collision behaviour of hydrocarbon droplets , 1992, Journal of Fluid Mechanics.

[29]  Michele Zagnoni,et al.  A microdroplet-based shift register. , 2010, Lab on a chip.

[30]  Olli Ikkala,et al.  Superhydrophobic Tracks for Low‐Friction, Guided Transport of Water Droplets , 2011, Advanced materials.