Graphene (Gr) has shown a significant role in photovoltaic applications due to its exclusive properties. In this study, we established a facile approach to fabricate p-Gr/HfO2/n-silicon, a metal–insulator–semiconductor (MIS) Schottky junction solar cell. Nevertheless, the poor work function of Gr and high-density defect states at the Gr/Si interface obstruct the efficiency of solar cells. To avoid this problem, the optimal thickness of the interfacial layer (HfO2) is employed, which circumvents the recombination process at the Gr/Si interface. Additionally, to boost the Schottky barrier height and Gr’s work function, a combination of p-type co-doping of organic molecule 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ) and Br is studied. Therefore, a higher work function aims to encourage the built-in potential, which ultimately improves the open-circuit voltage and current density and deteriorates the series resistance of solar cells. Hence, a unique combination of dopants resulted in improved efficiency of up to 12.31%. Moreover, devices with double layer (MoO3/HfO2) passivation have been enabled to provide outstanding stability for over 180 days. The combined effect of p-type co-doping and double layer passivation developed a solar cell having a significant efficiency of 14.01%. Thus, this work intends to show a promising, high-performance and stable MIS Schottky junction solar cell for massive commercialization of photovoltaic devices.

In this study, P3HT:PC 61 BM was utilized to fabricate flexible organic solar cells (OSCs) on the polyethylene terephthalate substrates under an ambient atmosphere. An efficient electron transport layer (ETL) was employed to achieve a better device performance. The ETL was fabricated by making a nanocomposite from zinc oxide (ZnO) and polyethyleneimine ethoxylated (PEIE). The PEIE doping causes the reduction of work function of ZnO as well as passivates the interface, which ultimately improved the performance of the solar cell. The ZnO device's performance was 0.80%, which was effectively enhanced to 0.95% after the PEIE doping with an increase in the FF and J sc . The ZnO's reduced work function due to PEIE is responsible for easy charge conveyance from the photoactive layer to the cathode, which enhances the FF and J sc values. Besides, the flexible OSCs with the ZnO:PEIE ETL demonstrate more improvements in the mechanical property than with ZnO. The device with the ZnO:PEIE ETL sustained around 80% of its original power conversion efficiency (PCE) after 800 bending cycles. Thus, this study can contribute to the future large-scale manufacturing of flexible OSCs by using the ZnO:PEIE ETL.

The diversity of brain functions depend on the release of neurotransmitters in chemical synapses. The back gated three terminal field effect transistors (FETs) are auspicious candidates for the emulation of biological functions to recognize the proficient neuromorphic computing systems. In order to encourage the hysteresis loops, we treated the bottom side of MoTe2 flake with deep ultraviolet light in ambient conditions. Here, we modulate the short-term and long-term memory effects due to the trapping and de-trapping of electron events in few layers of a MoTe2 transistor. However, MoTe2 FETs are investigated to reveal the time constants of electron trapping/de-trapping while applying the gate-voltage pulses. Our devices exploit the hysteresis effect in the transfer curves of MoTe2 FETs to explore the excitatory/inhibitory post-synaptic currents (EPSC/IPSC), long-term potentiation (LTP), long-term depression (LTD), spike timing/amplitude-dependent plasticity (STDP/SADP), and paired pulse facilitation (PPF). Further, the time constants for potentiation and depression is found to be 0.6 and 0.9 s, respectively which seems plausible for biological synapses. In addition, the change of synaptic weight in MoTe2 conductance is found to be 41% at negative gate pulse and 38% for positive gate pulse, respectively. Our findings can provide an essential role in the advancement of smart neuromorphic electronics.

With the current evolution in the artificial intelligence technology, more biomimetic functions are essential to execute increasingly complicated tasks and respond to challenging work environments. Therefore, an artificial nociceptor plays a significant role in the advancement of humanoid robots. Organic−inorganic halide perovskites (OHPs) have the potential to mimic the biological neurons due to their inherent ion migration. Herein, a versatile and reliable diffusive memristor built on an OHP is reported as an artificial nociceptor. This OHP diffusive memristor showed threshold switching properties with excellent uniformity, forming-free behavior, a high I ON /I OFF ratio (10 4 ), and bending endurance over >10 2 cycles. To emulate the biological nociceptor functionalities, four significant characteristics of the artificial nociceptor, such as threshold, no adaptation, relaxation, and sensitization, are demonstrated. Further, the feasibility of OHP nociceptors in artificial intelligence is being investigated by fabricating a thermoreceptor system. These findings suggest a prospective application of an OHP-based diffusive memristor in the future neuromorphic intelligence platform.

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