In this paper, multi-walled carbon nanotubes (MWCNTs) were successfully immobilized on the surface of a glassy carbon electrode by mixing with horse-radish peroxidase (HRP). The electrochemical behavior of H2O2 was also studied with the MWCNTs-HRP modified electrode as a working electrode. The MWCNTs-HRP modified electrode showed excellent response of reduction current for the determination of H2O2 at the potential of -300 mV (vs. Ag/AgCl). We assembled the MWCNTs-HRP modified electrode in a thin-layer flow cell and the H2O2 solution was continuously introduced into the cell with a syringe pump. We optimized the sensitivity of the H2O2 sensor by adjusting the working potential and the pH of the buffer solution. The peak current increased linearly with the concentration of H2O2 in the range 3.0 x 10(-7) to approximately 2.0 x 10(-4) mol L(-1). The detection limit is 1.0 x 10(-7) mol L(-1) (S/N = 3). The interferences from ascorbic acid, uric acid and other electroactive substances can be greatly excluded since the sensor can be operated at -300 mV. Stability and reproducibility of the MWCNTs-HRP chemically modified electrode were also studied in this paper. Fabricated with glucose and lactate oxidase, the MWCNTs-HRP electrode was also applied to prepare the on-line glucose and lactate biosensors because of the high sensitivity for the determination of H2O2.

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Wide‐bandgap (WBG) perovskite solar cells (PSCs) are acknowledged as promising candidates for multijunction tandem and building photovoltaics, which attract broad research interest in related research communities. However, the performance of WBG PSCs based on the mixed‐halide perovskites still lags far behind their pure‐iodide counterparts because of the complex compositional evolution, huge photovoltage deficits, and intrinsic spectral losses. Here, by comprehensively understanding the representative WBG PSCs, the main “WBG drawbacks” from the device point of view are discussed in‐depth and three intrinsic critical issues for the growth of high‐quality WBG perovskites are proposed. The prospects for WBG PSCs toward future advancements and commercialization are also presented to guide the coming research hot spots.

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Highly conductive n-type CH3NH3PbI3 single crystals are grown by bismuth doping and the optical fingerprints of bismuth induced donors in CH3NH3PbI3 perovskites are identified.

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Improvements in the light-harvesting capacity and the carrier extraction are both significant to improve the photovoltaic performance of perovskite solar cells (PSCs). It has been proved that local surface plasmon resonance (LSPR) based on metallic nanostructures is practical for capturing light to enhance light harvesting. Motivated by this, a special shaped Au nanoparticle, e.g., nanooctahedrons (Au NOs), with a broadband LSPR peak and a suitable size is controlled synthesized and applied in a PSCs device. The power conversion efficiency of PSCs is increased from 16.95 to 19.05% with a short-circuit current density (J sc) as high as 23.63 mA/cm2. Besides the enhanced light-trapping effect of Au NOs LSPR proved by optical spectroscopy analysis, the Kelvin probe force microscopy results show that Au NOs can also effectively reduce the surface potential of the electron transport layer, which promotes effective photocarrier extraction at the interfaces. This paper sheds light on the question of how plasmon excitation and light localization might be used advantageously in high-efficiency photovoltaics.

Monolithic perovskite/Silicon tandem solar cells have reached a certified efficiency of 29. 1% in recent years. In this review, we discuss material design for monolithic perovskite/Si tandem solar cells, with the focus on the top-cell development to improve their performance. Firstly, we introduce different types of transparent electrodes with high transmittance and low sheet-resistance used in tandem solar cells. We then discuss the development of the wide-bandgap perovskite absorber for top-cells, especially the strategies to obtain the perovskite layers with good efficiency and stability. In addition, as a special functional layer in tandem solar cells, the recombination layers play an important role in device performance, wherein different configurations are summarized. Furthermore, tandem device cost analysis is discussed. This review summarizes the progress of monolithic perovskite/Silicon tandem solar cells in a pragmatic perspective, which may promote the commercialization of this technology.