We report the effect of n-n isotype organic heterojunction consisting of copper hexadecafluorophthalocyanine (F16CuPc) and phthalocyanatotin(IV) dichloride (SnCl2Pc). Their interfacial electronic structure was observed by Kelvin probe force microscopy (KPFM), and there is band bending in two materials, resulting in an electron accumulation region in F16CuPc layer and an electron depletion region in SnCl2Pc layer. The forming of organic heterojunction was explained by carriers flowing through the interface due to thermal emission of electrons. Furthermore, the carrier transport behavior parallel and vertical to heterojunction interface was also revealed by their heterojunction field-effect transistor with normally on operation mode and heterojunction diodes with rectifying property.
A high sensitive optical amplitude modulation magnetometer is investigated and demonstrated experimentally. We build an experimental platform for the atomic magnetometer and configure it as a Bell–Bloom magnetometer with amplitude modulation of 50% duty cycle square waveform. The open-loop input-output model is deduced from the Bloch equation and is verified experimentally. Instead of locking the frequency by using a voltage control oscillator, we realize a closed loop using the coils to generate a feedback field which avoids the stringent requirement of a high resolution frequency meter and markedly expands the dynamic range as well as the bandwidth. We realize an open loop sensitivity of 0.8 pT/Hz1/2 at 20 Hz using a single light beam, which exceeds that of the state-of-the-art Bell–Bloom magnetometers, and the corresponding closed loop sensitivity is 1.2 pT/Hz1/2.
Triboelectric nanogenerator (TENG) has attracted attention for flexible electronics in the past decade. MXene is gradually applied in TENGs for performance enhancement, but the surface triboelectrification mechanism still needs to be further investigated experimentally. Herein, an experimental approach of regulating MXene fluorine groups by alkalization as a contrast to validate the mechanism is proposed. The MXene film and alkalized MXene film are studied to exploit the surface state. Compared with alkalized MXene‐based TENGs, MXene‐based TENG obtains enhancement in open‐circuit voltage, short‐circuit current, and output power by 4.1 times, 4.6 times, and even 136.6 times, respectively. The excellent performance enables flexible sensing and energy harvesting. Notably, this work reveals MXene surface triboelectrification mechanism and might motivate a new approach for TENG performance enhancement.
We investigate the heterojunction effect between para-sexiphenyl (p-6P) and copper phthalocyanine (CuPc) using Kelvin probe force microscopy. CuPc films are grown on the inducing layer p-6P by a weak epitaxy growth technique. The surface potential images of Kelvin probe force microscopy indicate the band bending in CuPc, which reduces grain boundary barriers and lead to the accumulation of holes in the CuPc layer. The electrical potential distribution on the surface of heterojunction films shows negligible grain boundary barriers in the CuPc layers. The relation between band bending and grain boundary barrier in the weak epitaxy growth thin films is revealed.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.