The development of conductive inks is required to enable additive manufacturing of electronic components and devices. A gold nanoparticle (AuNP) ink is of particular interest due to its high electrical conductivity, chemical stability, and biocompatibility. However, a printed AuNP film suffers from thermally induced microcracks and pores that lead to the poor integrity of a printed electronic component and electrical failure under external mechanical deformation, hence limiting its application for flexible electronics. Here, we employ a multifunctional thiol as a cohesion enhancer in the AuNP ink to prevent the formation of microcracks and pores by mediating the cohesion of AuNPs via strong interaction between the thiol groups and the gold surface. The inkjet-printed AuNP electrode exhibits an electrical conductivity of 3.0 × 10 6 S/m and stable electrical properties under repeated cycles (>1000) of mechanical deformation even for a single printed layer and in a salt-rich phosphate-buffered saline solution, offering exciting potential for applications in flexible and 3D electronics as well as in bioelectronics and healthcare devices.

unique and outstanding optical properties such as high quantum yield (QY), strong absorption, and widely tunable band gap energy [8][9][10] accompanied by inexpensive solution processing techniques. [11][12][13] These PNCs have been successfully used in photon detectors operational in the visible wavelength range with photoresponsivity, R > 10 5 A W −1 , [14,15] and could offer further opportunities for UV applications. [16,17] Amongst device structures of particular interest are hybrid field effect transistors (FETs) that combine single-layer graphene (SLG) with PNCs. The performance of these devices, such as their response time, is affected by the slow, >1 s, redistribution of charge between the graphene layer and PNCs under light and/or electrostatic gating, [18,19] leading to the accumulation of a large amount of charge in the PNCs (7 × 10 12 cm −2 [19] ). This phenomenon can induce a range of interesting physical phenomena, such as an optically induced Stark effect, [20] large hysteresis on the gate voltage dependence of the graphene resistance, [19] and enhancement of the photoresponsivity. [21,22] However, to fully exploit the potential of perovskite/graphene structures, a comprehensive understanding of their properties is still needed. High magnetic fields are invaluable for interrogating fundamental physical processes Stable all-inorganic CsPbX 3 perovskite nanocrystals (PNCs) with high optical yield can be used in combination with graphene as photon sensors with high responsivity (up to 10 6 A W −1 ) in the VIS-UV range. The performance of these perovskite/graphene field effect transistors (FET) is mediated by charge transfer processes at the perovskite -graphene interface. Here, the effects of high electric (up to 3000 kV cm −1 ) and magnetic (up to 60 T) fields applied perpendicular to the graphene plane on the charge transfer are reported. The authors demonstrate electric-and magnetic-field dependent charge transfer and a slow (>100 s) charge dynamics. Magneto-transport experiments in constant (≈0.005 T s −1 ) and pulsed (≈1000 T s −1 ) magnetic fields reveal pronounced hysteresis effects in the transfer characteristics of the FET. A magnetic time is used to explain and model differences in device behavior under fast (pulsed) and slowly (continuous) changing magnetic fields. The understanding of the dynamics of the charge transfer in perovskite/graphene heterostructures developed here is relevant for exploitation of these hybrid systems in electronics and optoelectronics, including ultrasensitive photon detectors and FETs for metrology.

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All-inorganic perovskite nanocrystals (NCs) with enhanced environmental stability are of particular interest for optoelectronic applications. Here we report on the formulation of CsPbX3 (X is Br or I) inks for...