323 Pencil–paper on-skin electronics.
https://www.pnas.org/content/117/31/18292

322 Precious metal recovery from electronic waste by a porous porphyrin polymer.
https://www.pnas.org/content/117/28/16174

321 High-performance field-effect transistors are constructed from carbon nanotube arrays positioned with DNA templates.
https://science.sciencemag.org/content/368/6493/878

320 Aligned, high-density semiconducting carbon nanotube arrays for high-performance electronics.
https://science.sciencemag.org/content/368/6493/850

319 A silicon nanowire with an asymmetric shape preferentially directs charge carriers to produce a high-frequency geometric diode.
https://science.sciencemag.org/content/368/6487/177

318 Liquid-free, stretchable, non-faradaic ionic diodes, transistors, and transducers are developed using ionoelastomer junctions.
https://science.sciencemag.org/content/367/6479/773

317 A method of engineering efficient and stable InP/ZnSe/ZnS quantum dot light-emitting diodes (QD-LEDs) has improved their performance to the level of state-of-the-art cadmium-containing QD-LEDs, removing the problem of the toxicity of cadmium in large-panel displays.
https://www.nature.com/articles/s41586-019-1771-5

316 Large electrocaloric effects in oxide multilayer capacitors over a wide temperature range.
https://www.nature.com/articles/s41586-019-1634-0

315 A superconducting thermal switch with ultrahigh impedance for interfacing superconductors to semiconductors.
https://www.nature.com/articles/s41928-019-0300-8

314 Three-dimensional curvy electronics created using conformal additive stamp printing.
https://www.nature.com/articles/s41928-019-0304-4

313 Waterproof molecular monolayers stabilize 2D materials.
https://www.pnas.org/content/116/42/20844

312 Data storage in DNA with fewer synthesis cycles using composite DNA letters.
https://www.nature.com/articles/s41587-019-0240-x

311 CMOS-integrated memristive non-volatile computing-in-memory for AI edge processors.
https://www.nature.com/articles/s41928-019-0288-0

310 Nanoscale vacuum channel transistors fabricated on silicon carbide wafers.
https://www.nature.com/articles/s41928-019-0289-z

309 Graphene ribbons with suspended masses as transducers in ultra-small nanoelectromechanical accelerometers.
https://www.nature.com/articles/s41928-019-0287-1

308 Single-nanowire spectrometers.
https://science.sciencemag.org/content/365/6457/1017

307 The limitations of conventional chemical doping of polymeric semiconductors can be overcome by adding a second ionic species into the system, leading to enhanced doping, electrical conductivity and stability.
https://www.nature.com/articles/s41586-019-1504-9

306 Modern microprocessor built from complementary carbon nanotube transistors.
https://www.nature.com/articles/s41586-019-1493-8

305 An ultraflexible organic differential amplifier for recording electrocardiograms.
https://www.nature.com/articles/s41928-019-0283-5

304 A miniaturized multi-clamp CMOS amplifier for intracellular neural recording.
https://www.nature.com/articles/s41928-019-0285-3