The microwave dielectric properties and the microstructures of Nd(Co1/2Ti1/2)O3 (NCT) ceramics using starting powders of Nd2O3, CoO, and TiO2 prepared by the conventional solid‐state route have been researched. The dielectric constant values (ɛr) saturated at 24.8–27. Quality factor (Q×f) values of 37 900–140 000 (at 9 GHz) and the measured τf values ranging from −45 to −48 ppm/°C can be obtained when the sintering temperatures are in the range of 1410°–1500°C. The ɛr value of 27, the Q×f value of 140 000 (at 9 GHz) and the τf value of −46 ppm/°C were obtained for NCT ceramics sintered at 1440°C for 4 h. For applications of high selective microwave ceramic resonator, filter, and antenna, NCT is proposed as a suitable material candidate.

We report the microwave dielectric properties and the microstructures of Nd(Co1/2Ti1/2)O3 ceramics prepared by the conventional solid‐state route. The prepared Nd(Co1/2Ti1/2)O3 exhibits a mixture of Co and Ti showing a 1:1 order in the B site. Lowering the sintering temperature (as low as 1260°C) and promoting the densification of Nd(Co1/2Ti1/2)O3 ceramics could be effectively achieved by adding CuO (up to 0.75 wt%). At 1350°C, Nd(Co1/2Ti1/2)O3 ceramics with 0.5 wt% CuO addition possess a dielectric constant (ɛr) of 27.6, a Q×f value of 165 000 GHz (at 9 GHz), and a temperature coefficient of resonant frequency (τf) of −20 ppm/°C. By comparing with pure Nd(Co1/2Ti1/2)O3 ceramics, incorporating additional CuO helps to render a dielectric material with a higher dielectric constant, a smaller τf value, and a 20% dielectric loss reduction, which makes it a very promising candidate for applications requiring low microwave dielectric loss.

Poly(amic acid) (PAA) and polyimide (PI) can interact with Pb 2+ and methylammonium halide by forming Lewis acid−base adducts and hydrogen bonds, respectively. These interactions can passivate perovskite (PVSK) defects and enhance PVSK solar cell (PSC) performance. Here, PAA and PI polymers were used as PSC additives by using p-i-n PSC [ITO/NiO x /CH 3 NH 3 PbI 3 /with or without PAA or PI/ PC 61 BM/BCP/Ag], and PVSK's interactions with PAA or PI were explored through X-ray photoelectron, UV−visible, photoluminescence (PL), and time-resolved PL spectroscopies. In additive-derived PVSKs, defects passivation increased PL intensity and carrier lifetime. Field emission scanning electron microscopy revealed increased grain size, suggesting decreased grain boundary defects in PAA-derived PVSK. Moreover, 0.0497 mg/mL PAA/PVSK had high power conversion efficiency (14.16% ± 0.54% in control devices vs 16.80% ± 0.63%; highest = 17.85%). PAA/PVSK displayed excellent shelf life stability, with efficiency maintained at 16.57% ± 0.75% after storage in Ar-filled glovebox for >500 h.

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