The increasing diffusion of portable and wearable technologies results in a growing interest in electronic devices having features such as flexibility, lightness-in-weight, transparency and wireless operation. Organic electronics was proposed as a potential candidate to fulfill such needs, in particular targeting pervasive Radio-Frequency (RF) applications. Still, limitations in terms of device performances at RF, particularly severe when large-area and scalable fabrication techniques are employed, have largely precluded the achievement of such an appealing scenario. In this work, the rectification of an electromagnetic wave at 13.56 MHz with a fully inkjet printed polymer diode is demonstrated. The rectifier, a key enabling component of future pervasive wireless systems, is fabricated through scalable large-area methods on plastic. To provide a proof-of-principle demonstration of its future applicability, its adoption in powering a printed integrated polymer circuit is presented. The possibility of harvesting electrical power from RF waves and delivering it to a cheap flexible substrate through a simple printed circuitry paves the way to a plethora of appealing distributed electronic applications. Main text:The rising demand for automatic identification procedures has resulted in an increasing request of portable and pervasive devices, such Radio-Frequency IDentification (RFID) tags, which could be used, for example, to identify everyday objects through electronic serialization codes.In general, RFID devices can be classified depending on the frequency at which they operate.Low-frequency (LF) RFID tags work at 120-145 kHz (LF), high-frequency (HF) tags at 13.56 MHz (HF), and ultra high-frequency (UHF) tags operate at frequencies higher than 860 MHz. [1] Another typical classification of RFID devices is related to the presence or not of a power supply or battery. Active RFID tags contain their own power source giving them the ability to broadcast with a read range of up to 100 meters (far-field communication protocols), so they typically operate in the UHF regime. Passive RFIDs do not have any power supply: all the power required for operating the tag is generated by converting the alternating-current (AC) RF signal received from an antenna into a direct-current (DC) power supply. Thus, the RFID tag usually contains a low resistance antenna and a high-frequency rectifier for AC to DC conversion.Passive RFID tags usually can be read from few cm for proximity readers (near-field communication protocol) and up to 1 m for vicinity readers. Choice of the specific RFID device depends on the target application and it is typically a trade-off among required reading distance, costs and technological constraints. Cost-effective passive tags are more suited for high volume products of limited intrinsic value and the HF range is preferable where bulky coils, such as those required for LF, are not an option, and tag flexibility and ease of

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cost-effective manufacturing techniques. Organic materials can be processed from solution, mostly by means of printing and coating techniques, which are lowtemperature processes, enable mass production, and minimize the by-products. [4] Being these manufacturing techniques compatible with flexible, plastic and other low-cost substrates, there is a clear potential for the integration of additional electronic functionalities into mass-produced, consumer products. [5][6][7] In order to meet very stringent costs constraints, which do not allow integration of conventional electronic chips, all-organic circuits fabricated by means of scalable techniques are one of the best options.One of the main limitations hindering the adoption of all-organic printed circuits in real applications is related to their operating voltage. [8] In order to grant their portability and easy integration, these circuits need in fact to be powered by thin film batteries [9,10] and/or energy harvesters, such as plastic solar cells, [11,12] thus requiring maximum operation voltages of a few volts and low power consumption, while keeping reasonably high values of accumulated charge density and of current flowing into the circuits. Efficient low voltage operation can be achieved by acting on the capacitance of the dielectric layer, which should be as high as possible and at the same time guarantee optimal charge accumulation and transport at the semiconductor-dielectric interface of both holes and electrons, in order to enable complementary architectures to drastically reduce power consumption. [13,14] Many efforts have been recently devoted to the development of suitable polymer materials for gate dielectric applications, aiming at the achievement of the highest possible gate capacitance. [13] Two main strategies may be followed, either increasing the dielectric constant of the employed material or decreasing its thickness. The integration of high-k materials as dielectrics is not straightforward, as the energetic disorder at the interface might interfere with charge transport inside the semiconductor layer. [15,16] Multilayer structures combining low-k and high-k materials have been therefore introduced. [17,18] However, high-k materials typically show dielectric relaxations occurring at low frequency, [19,20] possibly limiting the maximum operation frequency of OFETs. Such limit is particularly severe in electrolyte gated transistors, [21] where huge capacitances are achieved at the expense of the switching speed because of ions motion, even in recent solidstate electrolytes. [22] To avoid such limitations, an obvious In the path toward the integration of organic field-effect transistors (OFETs) and logic circuits into low-cost and mass produced consumer products, all-organic devices based on printed semiconductors are one of the best options to meet stringent cost requirements. Within this framework, it is still challenging to achieve low voltage operation, as required by the use of thin film batteries and energy harvesters, for which a high c...