NiMoV and NiO-based catalysts for efficient solar-driven water splitting using thermally integrated photovoltaics in a scalable approach

Abstract

Summary In this work, a trimetallic NiMoV catalyst is developed for the hydrogen evolution reaction and characterized with respect to structure, valence, and elemental distribution. The overpotential to drive a 10 mA cm −2 current density is lowered from 94 to 78 mV versus reversible hydrogen electrode by introducing V into NiMo. A scalable stand-alone system for solar-driven water splitting was examined for a laboratory-scale device with 1.6 cm 2 photovoltaic (PV) module area to an up-scaled device with 100 cm 2 area. The NiMoV cathodic catalyst is combined with a NiO anode in alkaline electrolyzer unit thermally connected to synthesized (Ag,Cu) (In,Ga)Se 2 ((A)CIGS) PV modules. Performance of 3- and 4-cell interconnected PV modules, electrolyzer, and hydrogen production of the PV electrolyzer are examined between 25°C and 50°C. The PV-electrolysis device having a 4-cell (A)CIGS under 100 mW cm −2 illumination and NiMoV-NiO electrolyzer shows 9.1% maximum and 8.5% averaged efficiency for 100 h operation.

Development of Various Photovoltaic‐Driven Water Electrolysis Technologies for Green Solar Hydrogen Generation

“…The schematic design and photograph of the integrated ACIGS + EC device are shown in Figure . Continuous optimization of the catalysts and the device layout [ 21 ] gradually improved the performance, as shown in Table 1. The final prototype (Type 2.2) achieved an average StH efficiency, under 1000 W m −2 illumination, of 11.3% LHV (maximum value of 13.5% LHV corresponding to an H2 of 3.7 g h −1 m −2 for the active area of 82.2 cm 2 ).…”

“…Thin-film silicon [20] ACIGS (1) [21] ACIGS (2.1) ACIGS (2.2) Silicon heterojunction [22] Silicon heterojunction PV approach Section 3.1. Using total PV area; b) LDH: layered double hydroxides; c) Max.…”

Nickel Site Modification by High-Valence Doping: Effect of Tantalum Impurities on the Alkaline Water Electro-Oxidation by NiO Probed by Operando Raman Spectroscopy

“… 4 − 7 For example, photovoltaic-driven electrolysis has benefits such as providing high efficiency, being cost-effective, and being part of an already commercially available system. 8 , 9 However, cost remains one of the main drawbacks in the success of hydrogen’s deployment, partly due to a lack of relevant mass manufacturing, in part due to a dependence on expensive raw materials. In this regard, alkaline water electrolysis ( eqs 1 and 2 ) is a hydrogen production method, offering both technological maturity and the possibility to replace expensive precious-metal electrocatalysts (commercial benchmarks) with earth-abundant alternatives cutting costs without ruinous compromises in efficiency.…”

The annual-hydrogen-yield-climatic-response ratio: evaluating the real-life performance of integrated solar water splitting devices

“…Moreover, a higher degree of integration is accompanied by the possibility to use the heat loss in the absorber as an efficiency boost via simultaneously enhancing the catalytic performance of the water splitting reactions, decreasing the ohmic losses, and cooling the absorber. [5][6][7] Whereas the installation and commissioning of electrolyzers in the multi-MW range is already ongoing in several countries, more integrated approaches still suffer from a low technology readiness level (TRL). While lab-scale PEC devices based on III-/ V dual-junction absorbers are reaching solar-to-hydrogen (STH) efficiencies of up to 19.3%, 8 the high material costs, non-trivial upscaling and long-term stability currently hinder practical applications.…”