{'fraction_non_alphanumeric': 0.03399765533411489, 'fraction_numerical': 0.03985932004689332, 'mean_word_length': 4.77027027027027, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Synthesis of columnar‐shaped CeO
 2
 and electrochemical sensor for detecting phenol

Highly uniform columnar-shaped CeO2 was successfully prepared in large quantities by calcining a precursor, which was prepared by a simple hydrothermal method. The structure and morphology of the precursor and the columnar CeO2 were characterised by X-ray diffraction and scanning electron microscopy. The columnar CeO2 was fixed on a glassy carbon electrode to obtain a columnar CeO2 sensor for detection of phenol. The anodic peak current was proportional to the phenol concentration in the range of 0.005–0.225 mmol l−1 (R = 0.995) and 0.225–1.125 mmol l−1 (R = 0.998) with the detection limit of 0.9 μmol l−1. This electrochemical method has the advantages of simplicity and ease of fabrication, rapid detection, low cost of the apparatus and wide dynamic ranges.